The manufacture of starch from potatoes and cassava

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Material Information

Title:
The manufacture of starch from potatoes and cassava
Series Title:
U.S. Dept. of Agriculture. Division of chemistry. Bulletin
Physical Description:
48 p. : incl. tables. illus., VIII pl. (incl. col. front) ; 23 cm.
Language:
English
Creator:
Wiley, Harvey Washington, 1844-1930
Publisher:
Govt. Print. Off.
Place of Publication:
Washington
Publication Date:

Subjects

Subjects / Keywords:
Starch   ( lcsh )
Potatoes   ( lcsh )
Cassava   ( lcsh )
Genre:
non-fiction   ( marcgt )

Notes

Additional Physical Form:
Also available in electronic format.
Statement of Responsibility:
By Harvey W. Wiley ...

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Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
aleph - 029684169
oclc - 28814437
lccn - agr09001092
Classification:
lcc - S584 .A3 no.58
System ID:
AA00025997:00001

Full Text


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POTATOE S GROW N I N ARISTOOK COUNTY. ME.






ULETIN No. 58.
U. S. DEPARTMENT OF AGRICULTURE,
DIVISION OF CHEMISTRY.










HE MANUFACTURE OF STARCH FRlOM

POTATOES AND CASSAVA.










By HARVEY W. WILEY,
CHIEF OF THE DIVISION OF CHEMISTRY.












SNo CO




WASHINGTON:
GOVERNMENT PRINTING OFFICE.
1900.
-'" ~l lf "! Ml..tt 3 .*i^H B iliB iir W S JL, A























LETER OF TRANSMITTAL.


U. S. DEPARTMENT OF AGRICULTUR
DIVISION OF CHEMISTRY,
Washington, D. C., April 19, 190.
SIR: I have the honor to transmit to you herewith the manusc
of a bulletin describing my observations in the manufacture of sta
from potatoes in Maine, together with descriptions of machinery
processes for the manufacture of starch from potatoes and
There are also included in this bulletin data relatig the id
of starch manufacture from potatoes in other parts of the country.
I recommend that this be printed as Bulletin No. 58 of the Divi
of Chemistry.
Respectfully,
H. W. WILEY,
ief of the Diviqion of |O6eistiy.
Hon. JAMES WILSON,
Secretary of Agcdtur.
2
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CONTENTS.

Page.
starch from potatoes --...----------------------..------................------- 5
Amount of product and description of soil---------------------------.............................. 5
to-starch industry in Wisconsin -and adjacent States ................ 6
Influence of commercial fertilizers on the quality of the potato .--------- 7
The composition of soils in which potatoes are grown.........------..... 8
Agricultural data----......--...------..---.. ..---........ ......-----. 9
Preparation of soil ----...--.--------.......-- .....-- --- ..-- ..--- 9
eed---------------................---..................................-------------------......... ------------------9
Time of planting ----.. ---------.......---.....---------------------. 10
Cultivation ......------ ........----..------.......---------------------------.......................-- 10
Harvesting---------- ------------------------------------- 10
Rotation---------------..........................---------------------------------............................... 10
Yield................------------..................---.......-------........------------------------- 11
t *% for srch making. yi ly 11
Potatoes ed for starch making....-....--........----.........-.........------------------ 11
Area under cultivation..----.......--------..--............-----------......... 11
Starch ores .......--....-------.......--....--........-------........................ 12
rocessof manufacture-----------.....---.....-. .-..-.......... 12
S ettling tanks----------------- -----..... --------------........--..-. 16
rying the starch ..-...--- --.. ---------------.......................... 17
Summary of the treatment of the starch upon the floors-............ 19
rling and shipping the starch ....---.......----------------................ 20
prices of various kinds of starches and of dextrins --................ 21
Uses of potato starch ............--.........------ ......--------------........------...-----.--------..... 22
Potato starch in the textile arts.-------.. --.........-- ......-...... 22
Potato starch as a source of dextrin...........-- ........ ............ 25
Sizing machines and processes-..-----....----..................---------.......----.......--.. 25
The use of potatoes for the manufacture of alcohol..----------..-------. 26
Washing the potatoes....................-.....-..-............... 26
Steaming the potatoes ..-.....-.......-----............--....... 26
The conversion of the starch into sugar -------.........------...- 26
Distillation -...- ----- 27
Distillation ...................................................... 27
hemical composition of Maine potatoes ............................... 27
Description of the potato samples................. .............. 29
constituents of Maine-grown potatoes.........-..................... 31
opic appearance of potato starch..... .--........................ 32
i ion of potatoes ..................-.........- .......--- ...33
Manufacture of starch from cassava.------------------------.......................................34
Cassava as an article of food.......................................... 35
Microscopic forms of cassava starch-----------------------.................................39
Methods of culture ...............----- 3...............................9
Plansfor a starch factory usig potatoes or asava...................... 42
Present status of the cassavaindustryin Florida....................... ---------------------44
3





















ILLUSTRATIONS.


PLATES.

PLATE I.-Potatoes grown in Aroostook County, Me........---......Frontipiece.
II.-Fig. 1, transporting starch to the kiln; fig. 2, starch warehouse20
III.-Fig. 1, barrels of starch ready for loading on wagons; fig. 2, wagon
loaded with starch ------..-----....--..---------................-------....--20
IV.-Cylinder slasher (plan, and sectional view )......--------.---..- 24
V.-Cylinder slasher (general view).. ----....-.---..................---
VI.-Steam-jacketed size vat-----------.............................--...........
VII.-Fig. 1, potato starch; fig. 2, potato starch, viewed with polarized
light --........................................................ 32
VIII.-Fig. 1, starch granules from cassava; fig. 2, starch granules from
maize ........................................ ....... 38

TEXT FIGURES.

FIG. 1.-Machine for washing potatoes...--...- ---.........---.........--- 12
2.-Section of surface of comminutor ................................. 12
3.-Rasping cylinder or comminutor ---................................ 1
4.-Rasping machine (cross section) --.................................. 13
5.-Plan of rasping machine......................................... 14
6.-Potato grater ..........................- .-..........-... 4
7.-Starch epa r .........................-.................... -15
8.-Settling tank .. .............................................. 15
9.-Starch washer (exterior view) ....................................
10.-tarch washer (interior view) ..............-..........-....... 17
11.-Drying kiln (end view) .......-- ....----- ..-- .............---.-- 18
12.-Drying kiln (end and side view).........---......-----------...--------..--19
13.-Upper floor of drying kiln......................................---20
14.-Starch drier (upper floor) --..........-...--- ---.....--........20
15.-Starch drier (upper floor), with shelving -----..................... 21
1.-Cassava plant, showing stem and root development ............-... 40
7.-Pla for starch actor --------..... --..............--------...........--
4






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THE MANUFACTURE OF STARCH FROM POTATOES
AND CASSAVA.



MAKING STARCH FROM POTATOES.

AMOUNT OF PRODUCT AND DESCRIPTION OF SOIL.

The total annual production of starch from potatoes in the United
States is about 15,500 tons,' of which 6,000 tons are produced in the
county of Aroostook, in Maine. The soil of this county presents a
nly rolling surface, and is composed essentially of drift, deposited
during the melting of the ice after the Ice Age, resting on a stratum
of limestone which in many places comes to or near the surface. The
soil partakes of the general nature of drift, containing a considerable
proportion of sand and the usual amount of organic matter. It is,
therefore, a soil which is peculiarly suited to the growth of potatoes-
a soil which does not pack after hard rains nor during periods of
drought. Its open and porous nature permits the free development
of the tubers and the evolution of rootlets both lateral and perpen-
dicular. The soil was originally covered with a growth of hard and
soft woods consisting chiefly of maple, cedar, birch, white poplar,
spruce, hemlock, and pine. The forest growth was dense, and in
clearing large quantities of ashes were produced, which fitted the
virgin fields particularly for the production of large crops of pota-
toes. After a few years of cultivation, the fields begin to lose a por-
tion of their natural fertility, and the potatoes are grown in these
sat the present time with a liberal application of farm manures
and commercial fertilizers containing a large percentage of potash.
The commercial fertilizers which are chiefly used for potato grow-
have, according to deterinations made in the Agricultural
Total production, 1899,15,500 tons: Maine and New Hampshire, 9,000 tons; New
York, 400 tons; Wisconsin and other Western States, 6,100 tons.






6

Experiment tation of Maine, the composition sh
table:
Composition of fertilizers used in growing potatoes.

Nitrogen. Phosphoric acid.
Trade name. As ammo A i- .
nia o og c. bo Total......

Per cent. Per cent. Per ct. Per cent. Per cent.
Chittenden's ammoniated bone phosphate....... 0.57 1.47 9.47 10.78 2.26
Chittenden's complete fertilizer .................. 1.45 1.98 10.24 6.47
Chittenden's market-garden fertilizer ............ 68 1.75 7.72 9.15 6.
Darling's blood, bone, and potash ................ 1.31 2.3 889 9.75 7.|6
Coe's Columbian potato fertilizer ................. .11 1.40 9.83 12.25 2.11
Coe's high-grade potato fertilizer ................. .75 1.77 9.19 11.69 6.11
Maine State Grange potato manure................ .75 .72 9.8 12.53 11.
Quinnipac potato manure ........................ .77 1.72 8.17 9.39 5.13
Sagadahoc special potato manure................. 1.03 1.11 6.96 10.96 7.
Standard special ................................ .47 1.73 8.96 11.32 .08
Stockbridge potato manure ...................... 1.54 1.74 6.90 9.4 10.0
Williams & Clark's potato phosphate .............. .77 1.59 8.30 9.21 4.61
Young's Excelsior potato fertilizer......................... 2.80 6.59 8.55 9.94


POTATO-STARCH INDUSTRY IN WISCONSIN AND ADJACENT STATES.

Wisconsin is one of the most important potato-producing States
and stands next to Maine in the production of potato starch. In the
immediate neighborhood of Stevens Point, in a triangular area of
which each side is about 30 miles, there are over 60,000 acres of pota-
toes grown. Mr. Horace E. Horton, a resident of that locality, says:
This belt is composed of glacial drift. The land adjacent to the Wisconsin River
is made up of level deposits of sand and gravel covered with a light loam, The
sand is usually found underdrained by a bed of coarse gravel.
Back from the river are uplands, a rolling surface covered with drift mposed
of clay, sand, gravel, and bowlders, variously intermixed. Sandy loam prevails.
Clayey loams occupy some areas, but are not prevalent.
The three great potato-producing counties are Portage, Waushaa, and aupaca,
the acreage planted in 1899 being 25,026, 19,960, 15,702, respectively. As a further
indication of the size of the industry, it is only necessary to state that Plnfield, in
Waushara County, has shipped as high as 1,965 carloads in one ; Hancock,
within 8 miles, 1,600 carloads. Waupaca, in Waupaca County, is o only to
Plainfield in shipments. The average yield of potatoes is 100 bushs per acre.
This potato belt is reached by two railroads. The connection with Easern con
sumers is the very best. A large part of the year, shipments are made by lake and
rail.
The potato-producing area is rapidly increasing. New settlements areg,
and the potato is the natural plant to follow forests and grass lands.
Factories are operated at Stevens Point, Waupaa, Black River alls, and Grant-
burg.
The industry is technically more developed in the West than in the East.
There are no varieties of potatoes grown in Wisconsin for textile purpes. The
starch factories must content themselves with the small, unripe, rotten,
unfit for edible purposes. The starch content is low, and with good factories
8 pounds of starch a bushel is a big yield; the average yield is fro 6 to 7 pounds.
The quality of the starch produced is not unifor; even in the same factory the
quality varies from day to day. Mechanical impurities abound. For certan textile
purposes doestic products an not be used an consumers import uropeanbrand
Siiiiii








The story of the indutry shows wrecks and is likely to show more in the imme-
diate future. The danger line of production equaling consumption is dangerously
near. f
There are factories in the West in operation at the following points: Traverse City,
ich.; Waupaca, Wis. (2); Stevens Point, Wis.; Black River Falls, Wis.; Grantsburg,
Wis.; Anoka, Minn. (2); Monticello, Minn. (11).
INFLUENCE OF COMMERCIAL FERTILIZERS ON THE QUALITY OF THE
POTATO.
It is shown by the data contained in the analyses of potatoes from
German sources, given farther on, that the use of commercial fertil-
izers influences the composition of the potato, especially in respect of
the quantity of starch it contains. The value of potash in producing
additional quantities of carbohydrates in growing plants has been
pretty well established by experimental work. It is evident, there-
fore, that the liberal use of potash not only favors the growth of the
potato in regard to yield, but also tends to increase the content of
tarch which it contains. The German experiments have indicated
also that a moderate use of nitrogen tends to slightly increase the
content of starch in the potato. An excessive use of nitrogenous
fertilizers is to be avoided. Extensive experiments have been made
in this direction by some of the agricultural experiment stations of the
United States, especially in Maine and Virginia, In Bulletin No. 92
of the Virginia Agricultural Experiment Station the results of the
experiments with fertilizers on the composition of the Irish potato are
given. The conclusions which were reached at the Virginia station
are as follows:
1i(1) That potatoes grown without fertilizers contain the greatest
amount of dry matter. The addition of fertilizers tends to diminish
the dry matter, and also as the quantity of fertilizer used is increased
the amount of dry matter is diminished.
(2) Potatoes grown where sulphate of potash is used contain more
dry matter than those where muriate is used.
(3) The ash is not affected to any very appreciable extent; fertilizers
tend slightly to increase it.
(4) Very little effect is produced on the starch by either the kind
or amount of fertilizers used; their tendency is to increase rather than
to diminsh it.
(5) Potatoes grown with muriate of potash contain less dry matter
bt slightly more starch than those grown with sulphate of potash.
(6) Neither the kind nor amount of fertilizers has any appreciable
effect on the percentage of nitrogen, phosphoric acid, and potash
contained in potatoes.
(7) The percentage of chlorin is considerably increased when
uriate of potah is used, and the ore uriate used the higher the
per cent of chlorin.






8

THE COMPOSITION OF SOS IN WHICH POTATOES ARE GROWN.

The study of a sample of soil representing any ve area gi
information only of the state in which it e ed at t moment the
sample was secured. Unless the field be a virgin one, the quality of
the original soil is not revealed by the analysis. Even in the of
the virgn soils of Maine it has already been noted tat their compo-
sition might be materially influenced by the large ties of hard-
wood burned during the process of clearing. The content of potash,
phosphoric acid, lime, and magnesia might thus be unevenly distrib-
uted. Several years of cultivation and cropping would be necessary
to secure a fairly uniform admixture of these inredients with the
soil, even supposing that any excess of the more soluble portions were
not removed by the rainfall.
The following data show the results of the analses of samples of
soil furnished by Director C. D. Woods, of the Maine station:
Compoion f two sample of aie sol
[Analyses by C. C. Moore and T. C. Trescot.

Constituents. Serial No., Serial No.
Constitunt 17.a

Per rent. Per cent.
Insoluble ... ..81.15 81.14
Volatileb ...................................................................... 8.14 8.16
Ferrie oxid (Fe a) ............................................................. 4'3 4.4
Alum ina (A ........................................................... 3.81 3.73
Mang ni oxid ( 0 ) ....................................................... .09 .09
Lim e ( CaO ) .................................................................... .43 .48
M agnesia (MgO )............................................................... .84 .7
Sulphuric acid (SO ).................................... .......................15 .1
Pho oric acid (..... .... .. ............................. .15 .15
Potash ( O) ......... ..................................................... 30
Soda (NaO ) ................................................................... 12 )
Carb nic ( a cid ( O e fo ........................................................... .16 .

a A qualitative test showed the presence of arsenic.
b CMtining nitrogen as follows: Serial No. 17.-554, 0.24 per cnt, Srial No. 17,555, 0.23 r cent.
c Not determined.

The above data show that the soils are siliceous but coan con-
siderable quantity of organic matter. They are reasonably rich in lie
and magnesia, which seem to be essential constituents of asoil suited
to the growth of ptatoes. The potash is also in fair quaity, but
not sufficient t produce maximum crops.
The two samples of soil are practically identical in compsition, and
hence it was not deemed necessary to deterine the alkali in the
second sample. The data show that the figures for the first sample
could be inseted wit perfect propriety to represent the second one.
The presence of arsenic in both samples of soil idicates the use of
paris green or some arsenical insecticide to proect the growing pot
vines from insect pests. The accumulation of arsenic in a il as a
result of the use of arsenical insecticides is a question of co derable
hygienic importance. It is fnot improable, from what is k n of the
tendency of plants to absorb soil constituents, that the resee of a




9

considerable quantity of arsenic in soils might, by the absorption of
n the growing crop, result injuriousl to the consumers of
ucts. The use of Bordeaux mixture on the potato vines
St the development of lds and rot is also a subject worthy
and has been considered in detail by the Maine station in a
bulletin which has just been issued.

AGRICUTTURAL DATA.
PREPARATION OF SOL.
eplowing of the potato fields is accomplished chiely in October
SNovember until freezing prevents further work. The soil is
to a depth of 6 or 8 inches and reduced to a proper tilth by
ws. In is condition it is left during the winter. When there
are ery snows protecting the soil from the cold, frost does not pene-
to a very great depth, so that upon the melting of the snows in
spring the soil is soon read for cultivation. If the snows of the
erly winter be small in quantity the frost penetrates to a greater
de and this prevents the early planting of the potatoes in the
following spring.
SEED.
potatoes which are used for seed are kept over winter in houses
ay built for the purpose. These hoes are built above ground
Sconsist of a double wall of boards. with a space of about 6 inches
een them, which is filled with sawdust. The room holding the
s is built over a cellar, in which a stove can be placed for use
g the coldest days of winter. The potatoes are kept in bins,
whic may hold several hundred barrels each. The walls of these
bins do not come in contact with the inner wall of the potato house
San air space is left between them. Between these ins air holes
ar bored in the floor, connecting with the cellar, so that the air
which is warmed by the stove can rise and circulate in the air space
beteen the potato bins and the inner wll of the house. The object of
his is to prevent the freezing of the potatoes in the very cold periods
f wnter, when the thermometer sometimes falls to 30 or 4 below
zo. The further object. however, is to keep the potatoes as cool as
psible, only a few degrees above the freezing point. In fact, the
te rure may fall for a short time to two or three degrees bow
the freezi point without danger of injuring the potatoes, since the
het pruced by their vital activity is sufficient to protect them
against a slight deree of freezing. In Wisconsin, brick warehouses
are preferred.
Aroostook County (Me) seed potatoes are well known in all
parts of the country, and arge quantities of the are annually sold in
other States for seed production. One farner during the spring of






10

1898 sent 14 carloads f seed potatoes to T
ments are reasonably low, the rate to Boston being 21 cents per 100
pounds. Where a single barrel only is sent the rate to Boston is 85
cents per barel. Shipments are made mostly in bulk, o w
potatoes are to be transferred to a boat, in sacks.
TIME OF PLANTING.'
The potatoes are planted chiefly during the month of June. This
gives ample time for their growth and maturity by the first or mi
of September, when the harvest begins. The planti is done in rows
30 inches apart, by means of a potato dropper. The toes which
are used for seed are usually cut into two or more ieces before
planting. (Pl. I.) When a fertilizer is employed the drill droppin
the potatoes also places the fertilizer in the row. Ferti rs are not
used broadcast. By the use of the machine above mentioned the
planting takes place with great rapidity, a mn and two horses b
able to plant from 6 to 8 acres per day.
CULTIVATION.
When the potato tops show above the ground they are first covered
lightly by means of a plow. On making their second appearance they
receive ordinary cultivation with a horse cultivator and a horse hoe
to keep out the weeds and keep the surface of the soil wel stirred,
the final cultivation being secured by throwing the soil against the
plants and forming a ridge. The whole of the cultivation is by means
of horse plows and hoes, the hand hoe not being used except in isolated
instances. A good team and driver are able to cultivate about 20
acres of potatoes.
HARVESTING.
The potatoes are harvested with a digger, which enters the ridge
far enough to lift the deepest potatoes to the surface The soil and
potatoes together are first received on a platform built in the shape
of a grating, the spaces between the ars being large enough to per-
mit the soil to pass through, but holding all the potatoes except those
too small for the market. This table is given a shaking motion, so as
to break up the soil and have it pass speedily through the Se
eral different kinds of harvesting plows are employed, bt the gener
principles upon which each one is built are as described above.
ROTATION.
In many instances potatoes are grown exclusively for sever ye
on the same soil. Usually, however, a rotation is p, of w
the following is a type: Potatoes, oats, grass, the field bing kept in
meadow for two ears. Clover is ofte sown with
flourishes in the vicinity of Aroostook ounty. In the fourth or








S e land is again planted to potatoes. Other methods of
also practiced, but they do not differ essentially from that

owing are plans of rotation followed on two German farms
potatoes for the manufacture of alcohol and starch:

1. Wheat. 1. Potatoes.
2 Wheat and rye. 2. Potatoes.
3. Potatoes. 3. Potatoes.
4. Peas. 4. Potatoes.
5. Rye. 5. Fallow.
6. Potatoes. 6. Clover.
7. Barley and oats. 7. Clover.
8. Red, and white, and yellow 8. Meadow.
clover; timothy. 9. Beans.
9. Grass. 10. Rye.

the first instance it will be seen that potatoes are grown twice in
rs, namely, in the third and sixth years of the rotation. In the
ecd scheme the potatoes are grown for 4 years in succession, and
hn for 6 years other crops are grown in the order shown.

YIELD.
yield of potatoes varies greatly with the character of the soil
nd te season. Ninety barrels per acre are considered a satisfactory
iand this is above the average. The barrel holds 2' bushels, and
e bushel weighs 60 pounds. Ninety barrels of potatoes, therefore,
epesent a weight of 13,500 pounds per acre. It has been found that
many localities in Aroostook County the yield of potatoes is dimin-
sheby the blight. Spraying repeatedly with Bordeaux mixture
p ily prevents the blight and greatly increases the yield.

POTATOES USED FOR STARCH MAKING.
Unless the price of marketable potatoes be very low, only the small,
n or refuse potatoes are sold to the starch factory. Whenever
Sprice of good merchantable potatoes is above 50 cents per barrel
e fmers find it more profitable to sell directly to the market. Dur-
ing e time of this investigation good marketable potatoes were sell-
i r $1 a barrel, and the starch factories were paying from 30 cents
ts per barrel for the refuse. It is evident, therefore, that the
l m the weight of potatoes entering the factory is very much
ln it would be if the whole crop of potatoes were used for

AREA UNDER cULTIVATION.
area planted to potatoein Maine in 1898 was 45,946
cres; in 1897 41769 acres, and in 1896 49140 acres. The estimated





11 2 iiI :,i"ii "iiii i ... .. .ii :i ,
12

quantity of starch made during 1898 was 6,000 tons. urig
period from September 1 to the latter part of
60 carloads of potatoes a day had been shipped out of county.
STARCH FACTORIES.
The number of starch factories in Aroostook County is about 45,
and the average cost of a factory complete is approximately $13,000.


d


fit III \\ ; I





FIG. 1.-Machine for washing potatoes: a, spiral of arms for removing dirt; b perforated screw for
moving potatoes toward end of washer next to the comminutor; c, perforated paddles for lfting
the clean potatoes into the hopper leading to comminutor; d, hopper for ntroducing potatoes to
washer; e, hopper leading to comminutor.

The average capacity of the factories is about 1,200 bushels of potatoes
a day, making a little over 20 barrels of starch of about 600 pounds
each. The average yield of commercial starch is 16 per cenof the
weight of potatoes employed, the starch holding from 16 to 20 per
centof moisture. This yield
is secured only when po-
tatoes of the best grade
are used. Poorer potatoes
yield only from 6 to 7
pounds per bushel of 60
. .. - pounds.

...... PROCESS OF MANUFACTURE.

.... .........The process of nanufac-
ture is extremely simple.
The potatoes, which are
--- kept in a storehouse, are
carried, after weighing, to
FI(i. 2.-section of rfae of4 cmiiutm r. a revolving washer about
12 feet in length and from 18 to 24 inches in diameter. They are
pushed toward the comminutor through the washer by means of
a perforated spiral or by arms attached to a reolving axle. A
stream of water flowing in a diection opposite to that of t motion
of the potatoes secures the final washing with clean watr. e p








iple of the washing apparatus is shown in fig. 1. By the time the
ave reached the comminutor they are practically free from
it ad grit.
rasping machine consists of a cylinder about 30 inches in diameter
6 inches long. This
ylinders made of wood
and is covered with pieces ...
f sheet iron punched full -- ............... .
of holesabout one-eighth of .:.. :::..........
an inch in diameter, as indi-
cated in fig. 2. The rough
edges of the iron, resulting
from the punch, face out-
ward. These pieces of iron FIG. 3.-Rasping cylinder or comminutor.
are nailed on the cylinder in
ections, and when they have become dulled by use they are taken off
and replaced by new sheets. The rate of revolution of the cylinder
is about 600 per minute.
if Some of the rasps are much
larger than the one just de-
Sa scribed, the one at Brown's
factory, in Holton, having a
capacity nearly double that
.just noted. The principle
j of the construction, how-
Sever, is exactly the same.
The rasping cylinder, with
a the iron rasps attached, is
.shown in fig. 3.
The rasp revolves as near
Sa brace of hardwood as can
be, and the potatoes, being
stopped by the brace from
passing, are reduced to a
fine pulp by the rapidly re-
Svolving drum (figs. 4 and 5).
Some of the modern fac-
tories have specially con-
structed rasps which are
FIG. 4-Raspmng machine (cross section): a, hopper; b, more effective than those
ra; recepte for p; d, buffer; e, setting screw; st described The
f, water jet. Justdescribed. Thepotato-
starch factories of Stevens
Point Wis., use a large-size rasp ma in Leipzig and having a
capcity of 250 bushels an hour. Other factories in the West use
Sater shown in fig. 6. A stream of water is thrown upon the






14

potatoes as they enter the cominutor, so that
washed through as it is reduced to the required
The various pats of the comminutor are shown in section in
fig. 4: a represents the hopper holding the potatoes; wl-
inder or rasp which revolves at a high rate of speed
which the potato pulp is
received after passing the
-rasp; d the wooden press
which is kept in position
ea ofte screw e
through the pipe f comes
the water which aids in car-
rying potatoes through the
rasp. The horizontal sec-
tion of the rasping machine
is also shown in fg. 5.
Another and more compact
form of potato rasp is
shown in fig. 6.
The pulp falls from the
rasper onto a starch separa-
-r-------~ -I:
FIG. 5.-Plan of rasping machine. on a t i
tor, the bottom of which
consists of wire gauze having thirty eshes to the inch ig. ). The
meshes, however, are not the thirtieth of an inch in diameter, since
the thickness of the wire must be deducted therefrom











li 11t



F(a. 6.-Potato grater.

openings of the mesh about one-sixtieth of an inch in diameter.
separator is slightly inclinie, so that the shaking prcss
the pulp toward the lower end. Th starch separator the
widh as the rasps, n ely, about 3 i e, and is 1 le
During the progress of the pi aong e separator,t te






15

ar ron it from pipes arranged above. The water detaches
he ar nules from the pulp, and the granules, being small
ngh to p through the meshes of the gauze, are carried through,
pl te p is left upon the screen, to be ejected finally at the lower
S rngement of theseparator and water jets is shown in fig. 7.

















FIG. 7.-Starch separator.

he pulp, which is a useful cattle food, is thrown away at all the
acries in Aroostook County. It does not pay to preserve it in a
otry where other forms of cattle food are so cheap. The best hay
el at the market in Presque Isle for $5 a ton.
i Wisconsin and some of the other Western States, the potato fac-













FIG. 8.-Settling tank.
os are siated o trout treas, and they are forbidden to run
herefuseto thesestreams. In such cases, the refuse is collected
n rge cist dug in the ground. The potato pulp can he fed in
reh condition witho bad effect to milk cows or to sters. With a
it care it an also be given to sheep, but usually it is alloved to
rli,;'i"iliii :






16

SE=TLING TANKS.
The starch, hich is carried through by the water, falls into large
tanks. These tanks, a type of which is shown in fig. 8, are of various
sizes, namely, from 20 to 40 feet in ength and wid
feet in dept. The starch, when it enters these tan wi
rapidly settles to the bottom, and the reddish-colored super
water can be drawn off. In a few hours after the ta is f
starch is all settled in a hard, compact mass in the of
The proportion of starch and water is such that a 4-inch layef sta
will result from a quantity of starch milk which would fil the ta
Inotherwords 4 inc
of starch are overlaid
with about 6 feet of
water.
SThe crude starch result-
ing from the above pro-
cess, after the water is
drawn o, is lifted by





is added at the same time,
and the starch is beaten
into cream and again
allowed to settle. (Ex-
tenor and interior views

shown in figs. 9 and 10.)
Fl.. 9.-Starch washer (exterior view). This process is simply
for washing the starch and removing the larger portion of impurities.
In the second settling the pure white starch first goes to the bottom,
and when the water is drawn off it is found to be covered with a thin
layer of starch mixed with varios forms of impriti This laer is
removed separtely, and the pure starch underneath is reavfor
drying tables.
The layer of dirty starch removed as above indicated is subjected to
a second washing, and, if necessary, to a thid, the final
of the starch which it contains being sometimes eff in sta
separators of the uual constrction. These are so co
the starch cream poured upon them permits the
starch during the flow of the liquid, so that by the time of the
screen is reached the starch is practically deposited and te rt and
.ORING .0W W Y.
r1' o ii iil







DRYING THE STARCH.
The wte starch derived from the process just described is dried in
kilns of two kinds. The old-fashioned kilns were heated directly by
furnaces, the hot air coming from the pipes being used to dry the
starch. In the modern kilns, the drying is effected by means of steam
coils. These permit a more uniform and more rapid drying, and at
the same time diminish the danger of fire, which is very great in the
kilns heated directly by furnaces. During the present season (1899)
three furnace kilns have been burned in Aroostook County. Very few
furnace kilns are now under construction, most of the new ones being
provided with steam heaters. The kilns are usually erected at a dis-
tance of 100 yards or more
from the factory, so that in
case of fire the factory build-
ing may not be destroyed.
In fig. 11 is seen the end
view of the drying kiln, look-
ing back from the fan c, which
forces the air onto the steam
coils a-a. The entrance of
the air is so arranged by a
conduit (not shown) as to
cause the whole of it to pass
over the coils d, in which very
cold water circulates. The
air in passing over the cold
pipes d loses a great part of ___ U" T_7
its moisture, so that it is as
dry as possible on reaching
th heating coils a-a. FIG. 10.-Starch washer (interior view).
The different platforms or
shelves on which the starch successively falls are shown at e-e-e-e.
Each shelf is easily reached by doors, the hinges of which are shown
at fso that the starch can be easily raked and made to fall
through the spaces between the slats of the shelves, as shown in the
figure. The bottom shelf is a solid floor, so that the dried starch
can be finally delivered into the troughs b--, which extend along the
full length of the drying kiln.
Fig. 12 shows an end and side view of the drying apparatus, the
details of which have been sufficiently indicated in the description of
the preceding figure.
Fig. 13 shows the top floor of a kiln heated by direct fire, the chim-
ney of the furnace appearing near the back of the engraving. This
il tion is drawn directly from a photograph.
Fig. 14 shows the top floor of a steam drying kiln, drawn from a
3632-No. 58- 2






18

photograph taken soon after the operation of placing the blocks of
starch upon the floor was commenced. Another of top oor is
shown in fig. 15, in which not only is the loor iel covered with t
blocks of wet starch, but in order to ncrease the d
are erected on which additional quantites of wet t can be p e
This illustration is also drawn from a photograph. All of the illu
trations above mentioned were obtained from phphs of th
tories in Aroostook County, Me.
















-4L














Fio. 11.-Drying kiln (end view).
After a few hours' drying the lare blocks of wet starch fal down
in smaller portions on raking, and these smaller portion fall t gh
the slats, shown in the figre, and are caught upon the shelves l
Thus, little by little, the starch which is raked throu te s ve
becomes drier and drier and is brought into contact wit r
In this way the starch granules are protected from s
version into a pasty mass, s would otherwis be the
subjected in the wet state to the full tenerature of t f







SUMMARY OF THE TREATMENT OF THE STARCH UPON THE FLOORS.
The stah is placed first upon the upper floors, on wooden slats with
penings of about half an inch. This is the coolest part of the kiln,
Sthat the sarch containing the greatest amount of moisture is sub-
ted to th least degree of heat. It is not safe to submit very wet
starch to a high temperature, for there would be danger in this case
of converting it into paste and rendering it unfit for market. When
e starch i partially dried it is raked over the grated floor, and the
particles ich are dry enough to be easily detached fall through and
strike simir grates below. This process of raking over the various
layers of rch continues until the starch in a fine powder finally
reaches the ow floor in a state of dehydration suitable for barreling.




















FIG. 12.-Drying kiln (end and side view).
It requires about twelve hours to complete the drying when the most
effective ins are employed, so that the kilns are charged with the
wet starch as a rule, twice a day. The size of the kilns is, of course,
proportiote to the capacity of the house. For a house using 1,200
rrels of potatoes a day the kilns are about 40 feet long and 30 feet
wde, and the shelves on which the starch is dried are about 15 feet in
height.
The dri tarch is finally raked off of the lower floor into a trough
g te ide of the kiln, whence it is placed in the barrels already
ntioned. In some of the steam kilns the drying is accelerated by a
bast prodcd by a blowing fan. The cold air, before being force
i he ki by the fn, is passed over a series of iron tubes filled
ith cold war, which takes from the air a considerable proportion








of moisture which otherwise would enter the kiln. It is evident,


starch rst the air beingig



successively cooled and be-
coming more and more sat-
plaed ihp iurated with moisture as it












-,-
elayers of starch. i
The wet starch in lumps



uof various sizes is trans-


Sof d nported over a bridge con-
necting the kiln and factory,
er eiter on a small railway or,



rmo re often, in wheelbar-
$IrI.fig. 1.i

THE STARCH.
.After the starch is thor-

Fiw. 1.-Upper floor of drying kilrn.the ah ,w
placed in heaps, in order that the moisture may be evenly distributed

some partns of the starchi
cose fhrom the kil much -
drier than others. If the
barreling take placea t once,
the ercentage of moisture
inc the mfrketed product is





not uniform. Uniformity
of moisture is securid by
placing the starch il large
wareh'llouses, w-here it re-





After tho mnass of Starch

t o oi Fl 14.-Starch drier (upper floor).

''An of tho product at this tim. is shown ill Pl. II, fig. 1, from


































c ~ ~ ; -' i:.




s,
I- 4





































bi itG tGK.
0 H
C-IIII










InI


ifi ~ii

1 .-TANBPOTING TARCHTO TH KIL.i~ F'G.r,,i 2*8AQ: AEHU












Ktf

oD





C






f-f
A,





13
A AW4D
0
















rn













FD

-I
m




FIG. 1 .--BARRELS OF STARCH READY FOR LOADING ON WAGONS. FIG. 2.--WAGON LOADED WITH STARCH.









taken in front of a starch warehouse at Presque
sle, Aroostok County, Me.
For convenience in han- -----



y the farmers for trans- -
18-



Sorting the starch. This
agon is characterized by a
Splatform, which makes e p)l
tvery comnvenient to handle
the s har which, on ac-
unt of its specific gravity,
Sextremely heavy when
barreled. A wagon of this
kind charged with its load
s s in II, fg. 2,

secured in Presque Isle,


IE PRICES OF VARIOUS

INDS OF STARCHES AND 4 / 4
FIG. 15.-Strch drier (upper floor), with shelving.
The wholesale prices of
the pricipal sarches and dextrins in the United States for the several
onths of the year 1899 are given in the following table:

Extreme wholesale prices of he principal commercial starches and dextrins for the year 1899.







.,.f... 5-84 44 6 6 -56 24-8
Month. Corn



an ...... 1.40-2.00 3 -4 .......... 5-6 3 4 5 -6 2.15-3
Feb...... 1.40-1.60 3 -41 -6 -4 41- 6 5 -6 51 -54 2 -3
Mar 1.40-1.60 4 8-6 4 41 -5 6 -6 51 -6 21 -3
Apr...... 1.45-1.60 41 41 .......... 5-6 4 -41 4t -5 461 51 -5 21 -3
May ..... 1.43-1.60 41 44 .......... 5-6 3 -4 41 -5 51 -6 51 -6 21 -3
June..... 1.40-1.65 4a -4j 7 -9-8 5-6 3j -4 4 -6 5 -6 51 -6 21 -3
July..... 1.44-1.65 4 -4 71-9 5-6 3 -4 41 -5 5 -61 51 -6 2 -3
Aug ..... 1.44-1.65 4 1 -4j 71-9 5-6 3j -4 4j -5 5j -61 54 5 6 2f -3
ept..... 1.3-1.60 4 -4 71-9 5-6 3 -4 4j -5 5j -6 6i -6 21 -3
Oct ...... 1.45-1-60 4 -4j 7-9 5-6 30 -3j 47 -51 5j -G 51 46 2J -3
Dee ...... 1.52-1.60 4 A 71-9 6-6 3i -3j 46 -5w- 5 64 5 - 21 -3
Minim 9-1.50 3 -31 7-81} 5-6 3I -3 4 -44 5 -6 61 -51 21-2.25
Xaxima. 1.55-1.65 4 *4j 71-9 5-6 4 -4z 4w -51 64 -7 6 21 -3
e s. -1.61 4.21-4.57 71-9 5-6 3.73-3.98 4. 63-4.96 87-6.17 -5. 4-.88 2.37-2.96

From the above table it will be noticed that there are very wide
ranges in the prices of starches of different origin, the indian-corn starch
of the highet grde eing the cheapest of all, while rice starch com-
mands the hirghest r ice.






22

Dextrin, or British gum, is one of the principal derived
from starch. The price of this article also varies g y, the impor d
dextrin and dextrin of domestic origin made from ees than
indian corn commanding the highest price, the import article, which
is made almost exclusively of potatoes, hang the highest price of all.
On the other hand, domestic dextrin made from indiacon starch
is only a little over half as valuable as the others

USES OF POTATO STARCH.

Potato starch possesses peculiar properties, rendering it especially
valuable for use in print works. Nearly all of the potato starch manu-
factured in Aroostook County is sold to print works in Mass
Rhode Island, and other parts of New England. The makers of prints
are willing to pay a considerable increase in price for potato starch
over that which they would have to pay for starch made from indian
corn. This higher value has led, according to information received
from several quarters, to the adulteration of potato starch with indian-
corn starch to a considerable extent.
In order to more fully present the valuable properties of potato
starch in the print works, the writer asked Mr. John Alden, a chemist
of mills at Lawrence, Mass., for a statement in regard to this matter.
In compliance with this request, Mr. Alden has kindly furnished the
following information in regard to the uses of potato starch in the print
works:
POTATO STARCH IN THE TEXTILE ARTS.
(1) Potato starch is used in the manufacture of cotton, linen, and silk
goods for three distinct purposes, viz: First, as a sizing for the arp yarn before it i
woven; second, for finishing the goods after they have been woven, bleached, dyed,
or printed; third, in the form of dextrin or roasted star, as a thickener or vehicle
for applying the colors to the fabric.
(2) The preparation of starch for sizing and finishing consists mainly in ixing
it with the proper amount of water in a wooden or metal tank, hich is provided
with a perforated metal pipe for blowing in stea so as to properly cook the starch,
or else the coking is done in an iron or copper kettle provided with a double bottom
for heating by steam under preure, and also provided with a stirring apparatus for
keeping the ingreients of the size or finish properly mixed during the cooking. The
starch mixture is iled from ten inutes to an hour or more, as the size maker
may deem best, and, after straining to remove any lumps or gritty matter, is ready
for use in the sizing or finishing machine. Besides the starch and water, various
other substances are dded to ipart peculiar qualities to the size Thus, to give
softness to the sized or finished yarns or fabric, it is customary to add so oil or fat,
at tallow, coanut oil, bone fat, or even soaps, before or during the boiling, while
various hygroscopic agents, such as glycerin and the chlorids of agnesiu, zin, or
calcium, are added to prevent the size from drying too much, so as to be harsh,
and brittle. The latter salts so act a antiseptics on heavily sized yarn or go
preventing the souring or mldewing which is iaeto take place when goods are
stored in a dap lace. When it is desired to make the yarn or far heavier
than it do i i its normal state, or to give the ods more bod e., e
i i.iii *i l|






23

and more closely woven-various white pigments are added to the
a clay, whiting, etc. Finally, to make the goods appear whiter, by
slightly yellowish tint of the natural fiber, even after it is bleached,
or bluish violet coloring matters are added to the size or finish, chiefly
tramarine or prussian blue.
represents, in general terms, the composition of the sizes and finishes,
individual sizer and finisher has his own receipts, which he considers to be
his own particular requirements, and a list of the ingredients used in those
would cover almost every chemical known. It is quite an art to be able to
or finish a fabric so as to imitate any sample that may be furnished, no matter
the fabric and fiber are the same or totally different. It is the business of the
Si c of the sizing to make a piece of cotton feel and look like a wool or
fabric, if he is requested to do so.
third use of potato starch mentioned above, its use in the form of dextrin for
ening colors, is no longer a very important one, as the various indian-corn dex-
have replaced the potato almost altogether, owing to their cheapness and greater
ing power. For very fine light work, especially in silk and wool printing,
to dextrin still holds its own on account of its lighter color and closer resem-
to gum arabic in its thickening properties. Its greater freedom from smell is
an advantage in certain sizing work. Potato starch itself is very little used in
ting, indian corn and wheat being the starches almost universally used. They
the action of chemicals better and give a more satisfactory working paste,
esides being much cheaper.
There is rather an interesting srvival of an old process very frequently carried
in connection with the preparation of potato and indian-corn-starch sizes, an
which accomplishes no particular object in its present use, although it had
purpose in its original application. I refer to the practice which holds in
millof fermenting or souring their starch before boiling it up. In England,
heat flour has for a long time been the principal agent used in the preparation of
for warps. The English have a practice of sizing their warps and also of finish-
their plain cotton cloth very heavily, so that in case such goods are exposed to
st warm atmosphere they are exceedingly apt to sour and even mildew. As is
ll known, flour contains quite a proportion of gluten and other nitrogenous mat-
which are very prone to decomposition, and it was found very early in the use
sizes that by subjecting the flour to a preliminary souring or fermentation process
it was boiled up into size, these nitrogenous matters would be broken up,
, and a size could thus be formed which would be very much less sus-
ble to souring. Potato and indian-corn starch do not contain enough gluten or
ous matters to warrant this long tedious operation, and while it is true that
process produces some slight changes in the starch itself, converting a
prporon of it into dextrin and maltose, thus modifying to a slight extent the
of a size produced from a soured starch, the same result can probably be
n a much simpler way by the addition of a small proportion of dextrin to
when it is boiled up. The souring process has been discarded in a great

The zing of the yarn is an intermediate operation between the spinning
weaving. As the yarn leaves the spinning frame it consists of a series of
or less twisted together, the ends of the individual fibers standing out
om the thread so as to make rather a hairy appearance. In order to stick down
ese loose ends and so make a smooth strong thread which will resist the wearing
the shuttle as it rubs swiftly over it, and also the chafing action of the reed
d harness, ithas been thecustom from the earliest times to give the warp thread
of some cementing material, called the size, the operation being called the
g or dressing of the warp. The size, having been properly prepared and boiled,






24

is run boiling hot into a trough at the front end of the
supplied with a steam pipe for keeping the size at a boil, al
the yarn under the surface and squeezing it thoroughly into the ber of the yarn.
As the yarn leaves the trough it between another of
remove theexcess of size, then between slat to
each other sothat they will not be all stuck together, and then it is passed over
drying cylinders to thoroughly dry it, and finally wound en roll at
end of themachine. Thisroll is put at thebackoftheloom itis fo
weaving.
The size for finishing the cloth is handled in a little different way. The cloth is
passed in some cases into the hot size or finish, then betweenqueee rolls and over
dry cans, or elseinstead of passingthe clot in thesizethelo rollof
machine dips in the hot size and carries more or less of it up i aa it
rapidly revolves. Either the back or the face of the cloth is r i c
this coated roll before it comes in contact with the squeeze roll it, thus
surface of the cloth is more or less coated with the size.
necesry in order to produce the various effects required fort
After being sized, the cloth is slightly moistened or spraed with and
through the different machines, calendrs, p beeles, stenters etc., for
ing, softening, lustering, dulling, watering, embossing, or prod
which is considered essential to the proper appearance of the
will be seen that there is an opportunity for utilizing the various
gums and starches and also the varous chemicals which may reton th inrdr
to produce these different results.
Of the several uses for potato starch mentioned above, by far the most important
is for the sizing of warps. Indian-corn starch is used altot for
poses, and, so far as I know, very little potato starch is used iii
spite of the higher price of potato starch, and it ranges gen to 100
cent higher than indian-corn starch, and also in spite of the fa that, weigh fo
weight indian-corn starch will give a stiffer paste than
for the latter that it is better for sizing purposes, especially f t sii i
yarns. Potato starch gives a more elastic size at the same i i imore
penetrating. Indian-corn starch size lies more on the the
potato starch, so that a given number of threads sized with te i
will take up more room when laid side by side than the s n
potato starch. Thus a cloth sized with indian-corn starch, tn w n ad t si
washed out, will give a more open fabric than if it had been
vided, of course, tt the yarn has been woven as close
is an old claim which it sees would be a proper subjet of sieific i ii
before it is accepted as fact.
The fact that the potato size penetrates more thoroughly and isi
the indian-corn size is the reason why the forer dut off n n
corn size.
Twenty years ago therewas not very much difference in the price of indian-co and
pota starh. Within the last five years the price of the fo
2 cents and I| cents for the manufacturers' grade, while the
averaged between 3 and 4 cents. Of course there are extree fluctuations outside of
these prices, as in the case of potato starch two years ago, w price dropped
to I cents This is not likely to occur again.
There are one or two preparations of potato as well as of instarch w
are coming into use as ingredients of sizes and finishes, used n connection with the
ordinay starch. One of the oldest of these is the exceedingly thick pasty prepara-
tion fored by kneading starch with strong caustic soda or potash. Soes the
alkali is artially neutralized without losing any of its thickenin roerties
~i ll ii;;iii
[:i sslll lIil; n~~






Bul. 58, Div. Chemistry, U. S. Dept. Agriculture. PLATE IV.








7 I- --- -0 -
t














(4 '1
6 ,S C-1
, - ""*" _


inyx







5 I" ,,
Nrx










1 i /I I"
o/
70t
00







c i I -







I I -/







I'



z 0_







Bul. 58, Div. Chemistry, U S. Deot. Agriculture. PLATE V.















.1//I //
C)














to



II
r~

)"i :i!:!















i h
!':, _ _
L17: }
ii'i


I ?` ii I -







But. 58, Div. Chemistry, U. S. Dept. Agriculture. PLATE VI.






































rc_
>



Ci)
-4








P1
< :.













.--ti






25

is formed by heating starch with a solution of zinc or magnesium
without pressure, by which an important change is effected in the
starch paste. They are sold in the paste or dry form to be used in
th ordinary starch size.

POTATO STARCH AS A SOURCE OF DEXTRIN.
pe large quantities of potato starch are used for the manu-
re of dextrin, or British gum, as it is often called. In the process
f anufacture the starch is'submitted to a high temperature, prefer-
Sin contct with the diluted vapors of nitric acid. The action of
hh in connection with the slight quantity of nitric acid present,
iciet to convert the starch into dextrin, in which form it is used
kind f mucilage, as, for instance, applied to postage and
Sthe sealing edge of envelopes, etc. The manufacture of
trin or gum of this kind is an important branch of the industries


SIZING MACIS AND PROCESSES.
Smachine emploed for yarn sizing is shown in Plate
Sw g a sectional view of the various parts of the machine.
Sgene vi of the same apparatus is shown in Plate V.
The oeis conducted as follows: When the yarn leaves the
it is wound on li tubes, and te a the yarn that is intended
os then wound off onto spools. From 300 to 400 of the
poo in a frame, the end of the thread on each spool is
d a wire loop, the loops being arranged close together
id siso that the yarn comes from them in a flat sheet, and it is
n w d onto a wooden roll a little wider than the cloth to be woven.
he isnow ready for the slasher, which is the ordinary name
sizing machine. The exact arrangement of te sizing
in Plate VI. The small brass immersion roll in the tank
t te let carries the yarn down under the boiling size, thence the
arn pass between the hollow copper size roll and the heavy solid
ro l on top of it. The object of this process is to press e size
oroughly into the fiber of the yarn and to remove any excess.
Inasmuch as an unbleached yarn is rather difficult o wet thoroughly
ith such a thick liquid as size, it is necessary that every yarn thread
uld be passed through a second pair of sizing rolls shown on the
ight of the figure. The bottom roll dips into the size so as to carry
t up to the yarn. The squeezed yarn then passes to the top of the
dry can, which is not shown in the figure, and generally over a
econ can where it is thorouhly dried. It then passes to the wind-
g h where the threads are separated and wound off on a single
athe extreme right of the machine.
The foreoing description and accompanying illustrations give a






26

general idea of how the size is applied to-the yarn, it is not the
object here to go into greater detail. The pof drying on
cans or on stenters, the spraying or damping, and e f finishing
or calendering are complicated operations pertaining epially to the
technique of the textile industry and not particularly to the
starch for the sizing material.

THE USE OF POTATOES FOR THE MANUFACTURE OF ALCOHOL.
In Europe nearly all the starch which is used or commercial and
technical purposes and a large part of the alcohol for the same pur-
poses are produced directly from potatoes. A brief summary f the
process of making alcohol from potatoes will prove of interest in this
connection.
WASHING THE POTATOES.
Various forms of machines are used for washing the potatoes, the
general principles of which are the same as those of the machine
already described and illustrated in fig. 3.
STEAMING THE POTATOES.
After the potatoes are free from dirt, they are taken, by means of
the elevator, to the steaming machine. The steaming machine consists
of a vessel of a size appropriate to the magnitude of the factory, and
capable of withstanding several atmospheres of steam pressure, with a
stirring apparatus, by means of which the potato paste, produced in
the process of steaming, can be uniformly mixed. If very thick pte
be required, after the potatoes are placed in motion the manhole is
closed; steam is introduced slowly until thee walls of the apparatus and
the potatoes become hot. By then opening the cock at the bottom of
the apparatus, the water of condensation which is produced is allowed
to escape. When the potatoes begin to become soft under the influ-
ence of the steam, the stopcock is closed and the steam is continued
with the stirring until the whole mass is reduced to a homogeneous
paste. The water contained in the potatoes furnishes an abundant
supply for the formation of the paste. The pressure of the steam is
usually from 22 to 31 atmospheres, producing a temperature of from
130 to 135 C. At this temperature the starch granules are disorgan-
ized and by the mechanical motion of the stirrer are reduced to a
pasty, semnifluid condition. Usually about three hours are employed
in this process.
THE CONVERSION OF THE STARCH INTO SUGAR.
Before fermentation can set in, it is necessary that the starch
the steamed potatoes be reduced to sugar capable of yielding to
action of the ferment germs. To do this, after the s ing is com
plete, a vacuum pump is attached to the s ing apparat ad d






27

the influence of the vacuum the pasty mass of starch, which is kept
i i i rapidly cooled, until the temperature reaches about 650
At this stage, a proper proportion of malt cream-that is, malt
x with a suficient quantity of water to form a thick semisirupy
id-is introduced into the mass and evenly distributed therein by
s of the stirrers. The diastase of the malt acts at once upon the
sar and converts it into maltose, a sugar which is easily acted upon
b the ferments for the production of alcohol. As the starch paste is
cverted into maltose it becomes thinner and thinner until at the
end of the operation it is in a liquid condition. The quantity of water
which is employed is such that the percentage of sugar in the mash
thus formed varies from 16 to 24. The saccharization of the starch
paste under the influence of the malt is accomplished in a very short
time and the liquid contents of the steaming apparatus are then ready
for transference t the fermentation vats.
FERMENTATION.
Fermentation takes place under the influence of yeast in exactly the
same way as fermentation of indian-corn starch is produced in the
manufacture of whisky and the fermentation of barley and other cereals
in the manufacture of beer. It is not proposed here to go into the de-
tails of the fermentation process, which, of course, varies with the
environment. The object is to conduct the fermentation at such a tem-
perature and in such a way as to secure the largest possible quantity of
alcohol from the sugar present.
DISTILLATION.
After the fermentation is complete, the alcoholic mass is subjected
to distillation in the usual way. Various forms of stills are employed,
but the most convenient one is a combination of the old-fashioned still
and the rectifiers' still. .By the operation of one of these stills a high
degree of alcohol, 95 to 96 per cent, of great purity, is produced at the
it distillation. If the object be simply to procure an alcohol in the
de state, the distillation is carried on in an intermittent still and the
holic product, which is quite impure, is afterwards subjected to
rectification.

CHEMICAL COMPOSITION OF MAINE POTATOES.
AIention has already been called to the fact that the potatoes used
or the manufacture of starch in Maine are usually the small, imper-
fet, or injured potatoes, which are separated from the better quality
ore sending to market, or they are the potatoes which by reason of
turity are not fit for table use. It is more profitable for the
ers of potatoes to sell their product, when ready for the market,
d lyto the groers or to the consumers than to the starch makers.









Any data, therefore, based upon the iperfect, injured, or
potatoes which are found in the starch factories would not be a fair
criterion of the potato itself as grown in Maine.
Through the courtesy of Dr. C. D. Woods, director of the agricul-
tural experiment station at Orono, Me., saples have been received of
Maine-grown potatoes, which are fairly representative of the potatoes
of the different varieties grown in that State. These sample were
submitted to a careful analysis to determine their content of starch.
For our present purpose it was deemed sufficient to determine the
moisture, starch, fiber, protein, ash, and specific graity.
The starch was determined in three different ways, nael, fro the
specific gravity of the potato, by washing the starch of the grated
potato through silk bolting cloth, and by the official method' of deter-
mining starch in potatoes. The data obtained from the first and ecod
methods were very unsatisfactory, varying somewhat more than 5 per
cent over the numbers obtained by the official method.
The numbers given in the following table are those obtained from
the official method alone.2

Analyses of poatoes gro in 1898, the rlts calculated to ater contnt t time of pling.

Variety. Serial Maine Moist Strch. Fiber. (i n T Specific
No. No. ure x 6. .) gravity

Per ct. Per ct. Per el. Per et. Per et. Per et.
Hebron............... 17538 3036 79.72 16.94 0.90 2.12 0.76 100.44 1060
Hebron ............. ... 17539 3037 78.13 18.59 0.72 2.06 0.78 100.28 1.0795
White Elephant...... 17O0 3038 76.81 19.96 0.84 2.19 0.9 100.79 1.067
White Elephant....... 1751 3039 76.92 20.38 0.90 2.31 0.87 101.38 1.0742
White Elephant ...... 17 3044 78.74 15.96 0.64 2.25 0.92 98.51 1.0803
White Elephant .... 1755 3045 75. 21 19.31 0.61 2.12 0.88 98.02 1.10 ~
White Elephant ....... 17 6 3046 75.88 18.81 0.56 2.2 0.96 98.46 1.0921
White Elephant ......1747 3047 77.44 18.12 0.63 2. 0 0.8 9913 1.006
White Elephant..... 1748 3050 75.56 18.14 0.56 1.81 1.04 97.11 1.1129
WNhite Elephant ..... 1759 3051 78.13 18.62 0.63 1.75 0.98 100.11 1.0 1
Delaware.............. 1712 3040 76.02 19.20 0.61 2.06 1.01 98.9 1.08
Delaware.............. 1753 01 7693 18. 0.61 2.19 0.94 99.30 1.0904
Delaware............. 17 3052 75.72 18.63 0.55 2.31 0.95 9.16 1.0745
Delaware ............ 17551 3053 77. 6 16. 2 0. 61 2.56 0.91 97.98 11120
Car en .............. 1752 30 76.87 18.03 0.66 2.06 0.0 9852 1 0967
Carmen ............. 1753 35 76. 57 17.07 0.59 2.3 0.76 97.37 I1.


irotm an inspection of the figures of the above table,it is evident
that the starch content of sone of the samples is quite low, In regard
to these Dr. Woods remarks, in a letter dated April 25,1899: "As you
probably remematbere, potatoes rrely Iliatture in Aroostook County
naturally. The tops are ither killed by blight or by frost. In accord-
ance with my experience the potatoes there grown are nore or le
inclined to be watery. This would seen to imply that the maximum
starch has not been developed."

'Se Bulletin No. 46, Revied, of the Diviion of Chemistry, p. 25.
-Analyws by W. 11, Krug anl T. C. TresCot (nitrogen).






29

DESCRIPTION OF THE POTATO SAMPLES.

The follwing description of the potatoes, the soils in which they
grown, and the methods of culture and spraying employed have
bee kindly furnished by Director C. D. Woods, of the Maine station.
numbers of the samples are those given at the Maine station:
o. 36, Beauty of Hebron.-Grown by C. H. Richardson, Fort Fairfield; sample
was taken from a field of 8 acres which had been in pasture since being cleared until
1896. In 1896 it bore a heavy crop of potatoes without any rust; in 1897 it was
planted to potatoes, with a light yield and an early rust. The yield in 1896
about 100 barrels per acre, and in 1897 about 50 barrels. The soil is light-red
loam, and like most land in that vicinity is'on a shell-like lime-rock ledge. The
eld was plowed in the fall of 1897, and harrowed three times in the spring with a
spring-toothed harrow. It was planted with a planter and hoed with a horse hoe.
The field had received no manure until in 1896; in that year, in 1897, and in 1898, it
received about 500 pounds of complete fertilizer per acre. In 1898 the crop was
planted May 10 and harvested between September 1 and 20.
The crop was sprayed twice with Bordeaux mixture, July 30 and August 9, but it
was too late to save the plants from the blight. The yield was about 50 barrels of
merchantable potatoes and 15 barrels of small ones per acre.
No. 037, Beauty of Hebron.-These potatoes were taken from a field adjoining
that from which No. 3036 was taken. The field was plowed for the first time in
the fall of 1897, and the crop was grown on the sod without the addition of any
fertilizing materials.
Nos. 8 and 3039, White Elephant, and 3040 and 3041, Delaware.-These samples
were from T. B. Bradford, Golden Ridge, Sherman, Maine. The land had a slope
to the north; had been in grass until October, 1897, when it was plowed. The
soil was dark, inclined to be wet, and was not underdrained. The subsoil was
gravelly. It received about ten 2-horse loads of barn manure, broadcast over the
field and about 500 pounds of fertilizer per acre; the fertilizer was applied in the
drill. The field was planted June 1 and harvested September'28. The whole field
was sprayed three times with Bordeaux mixture by the use of the Aspinwall sprayer;
in addition to this, sample No. 3038 was sprayed more with a knapsack sprayer.
At the time that had been sprayed five times, the others were killed by rust. There
were 45 barrels of merchantable potatoes and 75 barrels of small potatoes per acre.
All of the potatoes rotted very badly, and the decay began before any of the leaves
were killed.
Nos. 3044 and 3045, White Elephant.-These samples were received without the
name of the sender. No. 3044 was not sprayed, and No. 3045 was sprayed with
Bordeaux mixture.
o. 046 and 3047, hite Elephant.-These were grown by R. S. Hoyt, of Fort
Fairfield. The field has a slope to the northeast, and was in pasture previous to
1896. In 1897 a crop of potatoes was grown with the addition of 300 pounds of fer-
tilizer. The yield was about 60 barrels. The field was plowed again in October,
1897, harrowed May 20,1898, planted May 24, and harvested September 21. Four
undred pounds of comple fertilizer were used, applied in the drill. The part from
which No. 3046 was taken was sprayed twice, and 3047 was not sprayed. The yield
was barrels of merchantable potatoes and 25 rrel of small potatoes per acre.
Nos. 3050 and 3051, White Elephnt.-Grown by Powers Brothers, of Carihou. The
d bore potatoes in 1895; was seeded to oats in 1896, and grew a crop of red clover
1897. The soil is a medium light clay loam with a gravelly subsil. The field
was plowed in October, 1897, and arrowed in the spring. Four hundred pound
mercil fertilizer were applied in the drill, and the piece was plante May 15-19,







30

and harvested Septe er 20-25. The field was sprayed three but y
cumbed to the blight. The yield was 60 barrels of merchanand 13
rels of small ones per acre. No. 3051 was from anunsprayed of the fie
Nos. 305 ad 3053, s.-The name of the ender and the cultre is
known, except that 3052 was sprayed with Bordeaux mixture and 3053 was unspray
Nos.3054 and 3055, Carmen.-These were from the same as 3052 and
No. 3054 was sprayed with Bordeaux mixture, and 3055 was unspraed.

For the purpose of comparison it may be of interest to give the
table showing the mean composition of potatoes, given by Knig
Lintner, and E. Wolff.

Table showing mean composition of potatoes.


Constituents. Knig. Litner. E. Wolff.

Per Cetd. Per cent. Per cent
Moisture.......................................................... 75.48 76.0 75.0
Protein (N. x 6.25) ............................................... 1.95 2.1 2.1
Fat (ether extract)......................... ..................... ... ..15 .2 .2
Starch.......................... ................................ 20.69 18.7 20
Other nonnitrogenous materials .................................. 1.0 j
Fiber....................................... ................... .75 .8 1.1
Ash ................... ............. ................. ...... .98 1.2


A careful analysis made by Morgen of 38 different varieties of ot
toes gave the following results:

Table wing mean copositio of potatoes.


Specific gravity and constituents. Maximum Minimum. Mean

Specific gravity of the potatoes..... ............. ........... 1.134 1.04 1.1
Specific gravity of the juice............................ ...... 1 8 0216 02
Per ceni. Per cent. Per cent.
Dry substance......... ................. .................... 0.39 20.33 2557
Moisture....................... .. ............ .............. .67 9.61 74.
Juice .... .. ..... ... ....... ....... .... ... ....... ................ 7201 52.42 6102
Substunces soluble in water....................................... 5.17 2.66 3.21
Total nitrogen.................................................... .489 9 .324
Soluble nitrogen ....4...... ........... ....... ..... ... ...... .70
Insoluble nitrogen .................................. .......... ....... .100 .00
Proteid nitrogen .................................................. .225 .099 .141
Amid nitrogen .. ........................................... ..... .. 19 .073 .118
Other forms of nitroen....... ............................... .00 .01
Total carbohydrates calculated as sugar ........................ 27. 16.72.
Toal carbohydrNates ealculated a starch ...............4.55 15057 20.01
Btarch ............................................................ 24.260 14.532 16.61
Sugar ............................................................. .6 .OB 7
Dextrin ............................................................276 .0 9 .164
TotalI 1h... ............ ....1.208 6,50 1.076
aluble ah ................................................ ........... .
In oluble ash ....... .. ... ............................. ........... .477 .079 .262
. . . .. .. ..... .









einfluence of nitrogen on the starch content of potatoes is
sho in the following table, taken from Maercker's work on the
mau re of alcohol from potatoes:

Table showing influence of nitrogen on starch content of potatoes.

Fertilized.
Without nitrogen. With nitrogen.
i of potato.
Sp Yield of Yield of Yield of Yield of
Sarch. tubers starch Starch. tubers starch
per per per per
hectare. hectare. hectare. hectare.

Per cent. Kilos. Kilos. Per cent. Kilos. Kilos.
Se .:.e ........ .................... 18.01 20,900 3,780 18.17 24,870 4,507
Shampion ............................ 21.33 19,510 4,152 21.48 24,470 5,233
Imperator............................. 19.00 22,560 4,235 18.70 26,830 5,007
num bonum i.. --.................. 18.41 19,170 3,522 18.07 22,510 4,057
Auelie .........-- ........-......-.... 19.47 18,950 3,653 19.75 23,550 4,609
Reichskanzler .--....----.---------- -22.78 14,300 3,236 22.61 17,250 3,875
no............--- ..---------.. ----------- 19.33 17,590 3,422 19.92 20,900 4,199
Amaranth................-............. 22.47 16,180 3,619 22.84 18,310 4,188
harlotte ............................... 19.42 17,041 3,305 19.67 20,774 4,081
Glbfleischige Zwiebl.. ...............19.97 19,888 3,946 19.91 21,772 4,323
Dabersche -..........-..-.............. 21.82 17,377 3,778 21.80 20,313 4,399
Weissfiishige Zwiebel ................. 20.51 16,877 3,442 20.58 19,501 3,936
Schneerose........................... 18.84 19,653 3,724 18.66 22,343 4,186
Nassengrunder..... ..... ... . 19.08 19,701 3,725 22.12 21,889 4,813
elbe Roe...........................- 21.09 16,847 3,547 20.60 20,177 4,129
Hortesie............................... 17.72 22,416 3,907 17.45 26,381 4,532
Richters lange weisse................ 19.37 22,134 4,267 19.19 24,490 4,664
Rosalie....-............................. 18.27 19,866 3,557 18.25 22,186 4,003
Achilles ............................... 21.02 18,886 3,962 20.93 20,913 4,376
?) Alcohol. ........................... 16.47 16,270 2,673 16.31 20,339 3,327
Average .......................... 19.77 18,80 i 3,673 19.85 21,998 4,322


It is evident that liberal applications of nitrogenous fertilizers
increase the percentage of starch in the tuber and the yield per
hectare.
It will be observed in the above analyses that the potatoes of foreign
origin have a somewhat higher content of starch than the potatoes grown
in Maine. In explanation of this fact it is stated that for many years
systematic efforts have been iade in Germany and in other parts of
Europe to produce a potato rich in starch, not only for starch making,
t also for the manufacture of alcohol, since in Europe potatoes are
ost the sole source of commercial starch and commercial alcohol.
ese potatoes are not the best for table use, however. The potatoes
grown in Maine, although possessing a lower content of starch are
much superior in palatability for domestic consumption. The increased
content of starch, therefore, in foreign potatoes does not by any means
icate that the Maine-grown potatoes are inferior articles, but that
Sforeign-grown potato has been developed preeminently into a
s ch-producing vegetable.

ASH CONSTITUENTS OF MAINE-GROWN TATOES.

For the purpose of determining the extent of the mineral drain
n the soil by the otatoes grown n Maine, a comparative analysis











Analyses of the ash of potatoes.




175 47....047 56.16 1.62 1.38 .98 14.50 6.
17548........................... 8050 56.43 1.70 1.29 .76 1.00 .
17549 ......................... 3051 57.30 2.15 1.05 7 1

From these analyses it is seen that the principal min en
of potato ash are potash and phosphoric acid. The quantity of lime
remarkably small in comparison with the magnesia present. Sul-
phates are present in considerable quantities. Sand, carbon, silica,
carbonic acid, and chlor are not considered in above resul
which represent the constitution of the pure ash-tht the ash fr
of all impurities save carbonic acid. The difference bwn ths
of the percentages in each case and 100 represents the car ic aci
and errors of analyses.

MICROSCOPIC APPEARANCE OF POTATO STARCH.
The starch grains of the potato are among thet of the star
family, but are very variable in size. They vary fm 0.05 to 0.1
millimeter in length, are oval in shape-sonetimes almot rn
smaller granules. The oval forms have a breadth practically one-al
of their length. In Pl. VII, fig. 1, are shown starch grules fromi
potato grown in Aroostook County, Ae., as they appr nder
microscope. The drawings were made from the microscope y a
camera lucida. The magnification of the granules is diameter
The appearance of the field wuld indicate that the sm r nu
are not fully grown or ature-that is, that they repeset
ones formed in the growth othfhe potato, while the l r os
sent the granules which were first formed, and which have grown to
full size. The larger granules also have the appe e of
grown by aeretion, since they are marked by w
which are not shown in the smaller ones. These layers are shown by
rings, which seem to be concentric near one end of the ov
granules, and this origin of concentric rings is hi
hilum sometimes appears s a shadowy dpression. With polarize
light the structure of the starch granules is more clear ought out
as is shown in P1. VII, fig. 2, which the granules e md
same nu mer of diameters as in the precediig figure. Under
crosse d nicols with polarized light a well-defined dark c s i
1Analvyes hy C. Moor .





Bul. 58, Div. Chemistry, U. S. Dept. Agriculture. PLATE VII.
C,, ..-o" P ,.


:^ . ..T- ...y, .

SUt ( 2 O





'FIG. 1.-POTATO STARCH. X 300.)*










\i9, \ r/ 'i











F i I

FFIG. 2.-.POTATO STARCH, VIEWED WITH POLARIZED LIGHT ( 300300.).)
^ *





|- FG- .-POATOSTARH. IEWE WIH POARIED LGHT (x 00.






a 'he: I
33

n all the granules, even the smallest. This indicates that the starch
articles a joined together according to some crystallographic law.
y revolg one of the nicols the crosses change from dark tolight.
e plate the starch granules show rays of colors


DESICATION OF POTATOES.
ot potatoes may be kept for a long time and used in
e great variations of temperature exist, a process of
r evaporation has been applied to them with great success.
ly, in the desiccation of potatoes, the same principles are
Sthe desiccation of fruits. In the potato, however, the
r to be deat with is quite different from that found in fruit.
other fruits, which are usually subjected to the drying
S little starch is found, the prevalent carbohydrate being
sugar of some description. In the potato, on the contrary, the
of the solid material is starch. It is therefore highly
S process of evaporation to conduct the operation in
c a m r to avoid the breaking or swelling of the starch
the influence of moisture and heat. For this reason
Sporation should be begun at a very low temperature.
Sth wter which the potato contains is driven off, the temperature
be gradually raised, so that toward the end of the operation it
S en the boiling point of water without any great danger.
By prog in this manner, the process of evaporation is corm-
S causing the starch grains to swell or to become un-

Sevaporation begins, the potatoes are submitted to the
rning sulphur to protect them from discoloration. The
evaporation finally expels all of the sulphur fumes, so that
Scan be raised the consumption of this evaporated
te by on of the presence of sulphurous or even sulphuric acid,
ly cof which are formed by the sulphurous acid employed.
Sobable that the evaporated potatoes could be used for the
Sof starch, for although the strch granules have not been
St e form of a paste by the process of evaporation, never-
es the starch has been more or less changed in its nature by
a hih temperature, so that it partakes more or less of the
aracter of amylodextrin.
For nutritive purposes, however, the starch in the desiccated article
fullyasvaluable as in the original material, if not more so. Since
e desiccated particles contain all of the nutritious matter originally
resent in the potato, together with the cellulose, both digestible and
digestible, it is evident that the nutritive value of the material is
aior in any way to that of the potato in the original state.
L^^^ f s ^ S ^y-m11^^s






34

Thus, in the process of desiccation, e potato is redu a
in which it can be easily preserved bth in exeme ea e ee
cold, while its nutritive properties are not impaired to any a
extent. The desiccated potato, therefore, forms an elle il
for transportation to arctic or tropic reions, or o t n
our soldiers and sailors when distant fromsuppliesf fresh vegetab
The magnitude of the industry of the desiccation of p in
United Statesis not very great, but it is a business which prom
well for the future, in the preparation of certain fo of p
ducts suitable for special purposes.

MANUFACTURE OF STARCH FROM CASAVA.
In Bulletin No. 44 of the Division of Chemistry is found a descrip-
tion of the sweet cassava, with remarks on its culture, properties, a
uses. This bulletin is out of print, and it is therefore advisable, i
treating of the subject of the manufacture of starch from aaa
show the nature of its contents. Cassa ows in this count in the
southern peninsula of Florida, and well up into the frost belt, and is
also found in other of the extreme southern portions of the United
States. From a careful study of the climatic conditions under which
the plant flourishes, it is safe to assume that it may al be grown with
success in southern Alabama, Mississippi, Louisiana, Texas zona,
and southern California.
The name "cassava" should properly apply only to the puried
starch derived from the roots of the plant, but it has passed into gen-
eral use to designate the plant itself. I am informed by the Division
of Botany that the plant is known by various names, as, for instance,
JanOplAa miano/wt, JIan/iot util inu(t, Jatropka aniu ) ot, AJmihot alpi,
,lnJ1aot /la;~fng/q, and abnihlot poal ata. One of its common names
is manioc plant. The fleshy root of this plant yieldsthe test por-
tion of the daily food of the natives of many portions of tropica
Amnerica, and one of its forms of starch is imported largely into i
country as tapioca.' It is a woody or shrubby plant, growing f
fleshy, tuberous roots, the stems being smooth, with nodules where
the leaves grow.
There is properly only one variety of the plant 1growig in "Florida,
while that variety which grows in the Tropics contains s much hydr o
e.anic acid as to render it poisonous. The variety in
subtro)ical region of Florida, however, contains only a s ll qatit
of Iydrocyanic acid, and is therefore commonly knon weet c-
saa. Some of the growers of the plant in Florida claim that two
S111\, So) It, Of t he o)f the pa i n
'Three ftorms of tapiEoc are recognized in cimmerce, perl t a, a
and tali ca flour, The attr would b more appropriately called t
ra~4a~a 8hlrdl






35

r s gr in the State, one of which is poisonous on account of
the amount of hydrocyanic acid which it contains, and the other
on i, as it contains only a little hydrocyanic acid. It is quite
lhowever, that after the poisonous variety has grown for a
g w e in a subtropical climate it would lose largely its poisonous
pro ties. The leaves of the poisonous variety in the Tropics usually
seven branches, palmately divided. The leaves of the sweet
vaiety are usually only five-parted. The botanists clearly recognize
todistinct varieties. For instance, in the Treasury of Botany (p.
f78) the following remarks are made:
It is quite clear that while the root of one is bitter and a virulent poison that of
eother is sweet and wholesome, and is commonly eaten cooked as a vegetable.
ih of them, especially the bitter, are most extensively cultivated over the greater
of tropical America and yield an abundance of wholesome and nutritious food,
the poison of the bitter kind being got rid of during the process of preparation it
ergoes. The poisonous expressed juice, if allowed to settle, deposits a large
ty of stach known as Brazilian arrowroot or tapioca meal, from which the
pioca of the shops is prepared by simply torrefying the moist starch upon hot
plates, the eat causing the starch grains to swell and burst and become agglutinated
togther. A sauce called cassareep, used for flavoring soups and other dishes, par-
icularly the West Indian dish known as pepper pot, is also prepared from this juice
by concentrating and rendering it harmless by boiling. Another of the products of
is an intoxicating beverage called piwarrie, but the manner of preparing it is
not t to render it tempting to Europeans. It is made by the women, who
va cakes and throw the masticated materials into a wooden bowl, where
it is allowed to ferent for some days and then boiled. It is said to have an agreea-
ble taste.
CASSAVA AS AN ARTICLE OF FOOD.
The sweet cassava as grown in Florida is a common article of diet,
as well as the source of the domestic starch used over large portions of
e pninsula. The roots of the cassava are grated and used directly
as human food, and they are also fed to cattle, pigs, mules, and horses,
with very happy effects, being a food which is greatly relished. Cas-
aa flour i prepared as a domestic product in many parts of Florida
Sother localities where the cassava is grown. In the preparation
of c aaa flour the root is peeled, chopped into thin slices or grated,
spread in the sun for two or three days until sufficiently dry, and then
ground into a fine powder. In this state it is used for making a kind
of bread for puddings and for other culinary purposes. In the mak-
g of puddings the addition of milk, eggs, sugar, etc., to suit the taste,
Scommended. As a substitte for wheat flour in making bread, the
icaaa flour is of course inferior in general nutritive and culinary
rties. It contains an excessive amount of crbohydrates, and is
refore not as well balanced a ration s broad which is made from
eat. For instance, in ordinary wheat flour the nitrogenous bodies
Sfrom 8 to 14 per cent, while in cassava flour they rarely reach as
Sas 2 er cent. The chemical composition of the assava roots






36

and of the cassva flour, as determined in this bo
the following tables:

Composition of cassara root (dry matter).
Srial number. ..............................................5547
Per cent.
Ash .............--------------------------------....--..........---------------------- 1.94
Petroleum ether extract (fat) ...----...------... -----.. -....----...... ......---------------1. 27
Ether extract (resins, organic acids, etc.) .............--................... 74
Alcohol extract (amids, sugars, glucosids, etc )-------.....---.. ............... 17.43
Crude fiber ........................................................... 4---
Starch..............------.........-----..-....-...--..--...--------........... 71.8
Protein (nitrogen X 6.25) --------------............................................ 3.47
100.73
Composition of cassaa flour.
Serial numbers ...-..-----.. ---..... ----..---- --...-------5922 5923
Per cent. Per cent.
Moisture.............------...-.....----------- ---------.......... ...-- 10.6 1
Ash ......................-------- ...---.----------...-..-.....1.86 1.13
Petroleum ether extract (fat) .........-- ....-.................. 1.50
Ether extract (resins and organic acids) -..................-. 64 .43
Alcohol extract (amids, sugars, glucosids)--........................------ 13.69 4.
Dextrin, gum, etc., by difference...... ........................ 2.85 5.6
Crude fiber --- ----............................------..... ...--2.96 4.15.
Protein (nitrogen X 6.25) ----..................... --.....----------- 1.31 1.31
Starch................. --- -----------....-............... .3 70.1
Most extraordinary statements have been made in regard to the
yield of cassava per acre. Careful me.surements, however, made
under the direction of this Division, show that the magnitude of the
crop is usually very much less than is statedin the reports which have
been made. An average crop, under favorable conditions, may be
placed at 5 tons of roots per acre. In many cases, however, the yield,
where no fertilization is practiced and where the roots are grown upon
sandy soil, is much less than this. In the statement above, show-
ing the composition of the root, the analysis of a single sample of
roots is given. In order to determine the composition of a mor
general sample, large quantities of roots were obtained from Florida
and subjected to analysis, and the means obtained follow. I this c e
the roots were peeled in order to determine the co mpition of the
material as it would be prepared for human food. In addition to the
analysis of the peeled roots, the fiber remaining after the reoval of
the starch was also subjected o analysis, and likewise the bark whch
was remloved from the root. In thie cse of the bar, however, t
starch was not determined separately, but is included in the u r-
inied portion, forming, of course, ta considerable portion



*i~llP III~ l; i U:,l" ; 81i "; S#! "s "" |||






37

Composition of peelea root, and of the fiber and bark of the root.

Peeled root. Fiber Bark of root.
after re-
Constituents. moval of
Fresh. Dry. dry. Fresh. Dry.

SPer cent. Per cent. Per cent. Per cent. Per cent.
S........................................... 61.30 .................... 61.30 .........
Fat (ether extract) .................-.......... .17 0.44 0.30 .66 1.70
Protein (nitrogen x 6.5) .......................... .64 1.66 1.02 2.29 5.91
i extract inverted ith HCI) ...... 30.98 80.06 64.64 .........
Fiber ............................... .88 2.26 10.68 3.83 9.89
Ash-....-................ .. ....--- ---- ..- -..-..... .51 1.31 1.42 2.02 5.23
eter ed .................................. 5.52 14.27 21.94 29.90 77.27
Tot 100.0 .-------------------- 100.00 100.00 100.00 100.00 100.00

With the starch, in the analysis given above, is reckoned also the solu-
ble carbohyd aes, consisting almost exclusively of cane sugar, and of
which, in an analysis of another portion of the dry substance, as high as
17 per cent was found. In the laboratory it is not difficult to prepare
crystallized cane sugar from the aqueous extract of the fresh pulp.
I have made such a preparation. The percentage of sugar in the
plant, however,is too low to excite any reasonable hope of the prepara-
tion of this article on a commercial scale. The most promising way
to sve it is by conversion into glucose, as indicated in another place.
The undetermined portion consists of the digestible fiber and carbo-
ates of the pentose series. The pentosans in the fiber were deter-
mined by the furfurol process, as modified by Krug, and the amount
in the air-dried material was found to be 3.92 per cent, and in the
materil after the removal of the starch 5.33 per cent.
Th fresh root was found to contain 38.7 per cent of dry matter,
Sconsiderably more than was found in the fresh sample of the
Sanalysis. Of this 38.7 per cent, 30.98 consisted of starch and
soluble carbohydrates.
iEpriments were made to determine the yield of air-dry starch
ich could be obtained from the roots by laboratory work. Two sets
ofexperiments ere made. In the first set the roots were pulped on
a Pellet rasp, used for preparing beet pulp for instnantaeous diffusion.
Twelve kilos of the unpeeled root were rasped in this way and the
starch separated by washing through a sieve of bolting cloth. The
washings and settlings were collected and dried in the ordinary nmthod
:f starch manufacture. The yield of pure tarch was 3105 grams,
ivalent to 25.9 per cent of the total weight of the root. The
starch was almost absolutely pure, containing onlmy a trace of nitroge-
nousmatter. In the second experiment 10 kilos of the root were
gro in a pulping machine, used for preparing green fodder for
analys. The pulp was much coarser than that produced by the Pei-
sp. Treated in the same way, the yield of air-dry starch was
0 g s, or 23.6 per cent. One of the striking points in connee-
;,,, ** ;,






38


consisting largelyv of fiber, contained still a large percentage of starch,
showing that the process employed did not secure the whole of the
starch from the pulp. The diameter of the starch granules is a little
over 0.01 mm., being much smaller than the average of potato starch.
The relations f the mineral ponents of
plant food in the soil, with the exception of ni
from the ash. A large quantity of ash, therefore, was prepared fro
te peeled root and from the bark, and analyses of
obtained. The data are given in the following t

Analysif of the ash of the cassava roo

Peed root.
Constituents.
A. B. Mean. A. B. Mean.
Per cent. Per cent. Per cent. Per cent. Pr cent. Pe cent.
Carbon ............................. .. 0.30 0.31 0.31 0.79 0 7
Silica (soluble in solution of NaCO.... .97 .91 .94 10. 11.6 10.94
Silica (insoluble in solution of Na CO) 7.15 7.1 75 59 *2.16
Ferric oxid (Fe O ................... .6 .66 .66 2.44 2.4
CalFcium oxid (CaO) ..................... 10.63 10.64 10.64 .58 .65 .2
Sodiumoxid (NaO)...................... 1.12 1.28 1.20 .84 1.05 .91
Potasslum oxi d(KiO .-0 e -_-- 41.72 41.nm 4e1.6 14.7i 14.i8 14.7t
Sul ehuri acid (8i) ..................... 3.67 3.80 .7 1.71 1.71 1.71
Carbonic acid (COic...................... 9.15 9.2 9.14 2. 2.50 2.
Chlorin (CI).............................. 2.76 2.75 2.75 1.41 1.42 1.41
Total ............................... 101.07 101.10 101.08 100.32 100.65 100.42
Oxygen equivalent to chlorin ............ .62 .62 .62 .1 .1 .
Difference .......................... 100.45 100.48 100.46 100.01 100.22 100.11

From the above numbers it is seen that the ash of the peeled root is
especially rich in potash, almost one-half of the total weight being
composed of this substance. The potash is combined chiefly with ar-
bonic and phosphoric acids. In the ash of the bark, as might be
expected, silica is the predominant element, comprising more than
half the total weight.
Aumng a yield of tons of roots per acre, the weights of the
important fertilizing materials reimoved by sh crop can be readily
calculated from the data given.
Since the bark forms approximately 2.2 per cent of the entire root,
the total crop would be, ade up of the following amounts of bark

given below:
Rehare uto of k and pe root in a rop of aava, and amount of a content.








BuI 58, DIV. CHEMISTRY, U. S. DEPT. AGRICULTURE. PLATE VIII






-

















PLAIN ILLUMINATION.
eg .A e






















a r
G* 0o g




49







FIG. 2. STARCH GRANULES FROM MAIZAV X Iso
PLAIN ILLUMINATION.

A oen&Co Llthocast,
A. Hn li1 .~l i






important minera matters contained therein are shown in
the folloing table:

ble showig mneral maer contained in ash of peeled root and bark.

Ash from Ash fr Total ash
Ash from
Material.peeled ( t bark (4.44 (f 5 tos
pounds). pounds). pounds.)
Pounds. Pounds. Pounds.
me ( .....................................................5.31 0.29 5.60
Magnesia gO) .................................................. 3.67 .15 3.82
Potash ...................................................... 20.77 65 21.42
Ph acid (P. ).............................................7.77 .11 7.88
Residue .................................................... 12.56 3.24 15. 60

The less valuable mineral plant foods-that is, those that are of so
little no as to require no conservation or addition-amount to 15.60
p dper acre and the more valuable to 32.72 pounds per acre.

MICROSCOPIC FORMS OF CASSAVA STARCH.
S VIII, fig. 1, is shown a photomicrograph of the starch gran-
ulesderived from the cassava. The magnification -is 150 diameters.
size the starch granules of the cassava are much less than
S the potato, the mean diameter of the former being only .012
ii r. In size the particles of cassava starch are practically the
sae as the of the maize starch, which for comparison are shown
VIII fig. 2. The difference in outline, however, is very marked.
y of the maize particles hav an irregular polygonal perimeter,
the cassava starch granules are mostly even and regular in out-
line. Amongthe cassava starch granules are found a few which have
a very peculiar appearance, as if an elongated granule had been rolled
togeer so that the ends almost joined. This is a peculiarity of form
which, so far as I kow, is not found in any other variety of starch.
A few of the assava particles of starch are also found irregular in
outline, due to being placed close together in the substance of the
root, but this number is by no means so great as that of similar granules
aparing in maize starch. In general it may be said that the cassava
starch resembles that of maize in its microscopic appearance more
than any other common variety of starch.

METHODS OF CULTURE.
Csva was grown for one year at the Department experiment
station at Runnymede (post office Narcoossee), Osceola County. Fla.
rop was grown as food for stock. The field in which the crop
was grown is high-pine sand, with almost no other ingredient. The
illn of the cassava given herewith is from a photograph of a
from a ield near the station. The soil on which it was
ow was parentlY pure sand. It represents the larger plants in
",s,,;; iii,iiii" ;: , .* "" ,l;oi ;;






40

the field, but not by any means the largest. The illustration (fig. 16)
shows in a striking manner the stem and root developme
plant, of which the photograph is given, was feet i
in the soil occupy a more nearly horizontal position t is i
the figure. The thickened part of the stem, to whih roots re
attached, represents the cutting from which the plant gr
Attempts were also made to grow the cassava in a pieceof very wet
muck land at the station in which sugar cane would not w to any
advantage. An immense development of tops was s d, se
the plants reaching a height of 10 feet and resembling young t
The root development was fair, but not co mmens
with the top growth. Some of the stems were e 2 inches in
diameteri On well-drained muck land I
04 % think the crop would be large and
Sprofitable.
S"In sand land the planting should bepre-
ceded by the removal of stumps, sp s,
etc. and the soil given a thorough plow-
ing. It is advisable to spread about 300
pounds of ine raw Florida phosphate
floats or about 150 pounds of superphos-
phate containing 12 per cent available
acid to the acre. This may be applied as
a top-dressing and thoroughly worked
into the soil by a deep-running cultivator.
The rows should be marked out in fur-
rows 3 to 4 inches deep and from 3 to 4
feet apart. o get a good stand aut
double the number of cuttings required to
produce 2,50 hills per cre should b
planted. The excess of plants can be re-
FrI. I.-Csava ilnt, showing zt1m moved with a hoe as soon as viIgorou
an1d rt develop me nt. g "
growth is assured, leaving one hill every
3 or 4 feet. About 150 pounds of kainit per acre should e dropped
in the hills beore planting, together with an equal amount of cotton-
seed meal, or half that amount of Chile saltpeter nitrate of
The ctulttiaton should be such as to keep the field free of all weeds
and thesu of the oil well stirred. While the p are young,
deep cultivation is not objectionable, but as soon as theroot syst
begins to develop, supericial culture must be practic not to ex-
(red 2 inches in depth. Some cultivators draw the soil to the pla
during cultivation, so as to form a ridge at. the tie of lyg y.
Whoere nitrate of soda has been used an additional .0 or ~i o
per acre should be sown brondcast just before il ii






41

The above method is the one which should be followed for the poorest
kind of sa soils, where a maximum crop is desired. For muck
oi ls, the ',tton-seed meal and nitrate of soda should be omitted and
about 50 pounds of Florida phosphate floats used per acre. If sand
oilsare covered with a good layer of muck before the plowing the
nitrognus fertilizers may also be omitted or reduced in quantity.
In odinary seasons with the treatment outlined above, a crop of
frm4 to tons per acre will be secured. On sand soils containing a
litt organic matter approaching the hammock variety, a fair yield of
from 2 to 4 tons per acre will be secured by good cultivation without

For seed, the stems of the unfrosted plants are cut into pieces about
6 inches in length, care being taken that each piece has two or more
eyes. In planting, these pieces may be laid directry down in the
furrows and covered, but the general practice is to place them
obliquely in the furrows so that one end may not be covered. In case
of a threatening frost before a field is ready for planting, the unfrosted
tops may be cut, thrown into heaps, and protected with leaves or
trash from the action of the frost. They should, however, be
embedded in moderately moist earth -if they are to be kept for any
length of time before planting. In case of frost before the seed is
saved, the stumps, i. e., the points of union of the top with the root,
will usually be found uninjured, and these may be cut away and planted
instead of the cuttings just described. The larger parts of the stems
immediately above the ground make the best seed.
The roots should be left in the ground until they are needed for use,
wheher for food, for starch, or for glucose. The crop can be har-
S at any time during the year, but the best season is from Octo-
ber to May. The ots should not be allowed to grow more than two
seaons, and for most purposes it is believed that an annual harvest
will prove thee profitable.
As is the case with all new and promising plants, the most extrava-
t statements have been made in regard to the amount of cassava
which can be produced per acre. In many of the returns received
from our correspondents in Florida stateents were made in regard to
the yield which were entirely beyond the bounds of reason. These
extravagant statements. of course, did not proceed from any desire
on the part of correspondents to misstate the facts, but on ount of
teir miisapprehension of them. Statements of yield are made. as a
i le, not upon accurately measured and weighed products, but upon a
mere glance over a field or the taking of a few hills. It is easy, there-
ore, for the most honest and upright corespondent to fall into gross
ero in regard to the amount which will be furnished by an acre. In
m' own observation of small areas, and from the accredited statements






42

of those authorities which seem to merit the highest consideration, I
am convinced that on the ordinar pine land of Flori p
preparation and cultivation and appropriate fertilization, a yield of
from 4 to 7 of perhaps 8 tons per acre may be reas
It is difficult to see, however, how it is possible for such yis as h
been reported-viz, 40, 50, and'even 60 tons per ac-o be gat
In exceptional conditions, as is the case with all cro, excepti
yields may be obtained, but these must not be cond
tical study of the problem of profitable production.
The profit which the farmer may make from gro crop
the manufacturer from using it should, in my opinion, be ba upon
a yield of 4 or 5 tons per acre. If it be desired to from
the plant, we may suppose as a minimum rate of ield 20 per cent
of the weight of the fresh rootmay be obtained as mer
of a high grade. On a yield of 4 tons per acre this would amount to
eight-tenths of a ton, or 1,600 pounds. Compare this with the weight
of starch obtained from indian corn producing 40 bu s per
The yield of merchantable starch of a high grade may be plc at 35
pounds per bushel, which for 40 bushels would amount to 0
It is thus seen that the rate of yield per acre in the mattr of sta
from cassava would be fully equalif not superior to indian corn
If the mater of the manufacture of glucose be considered, the esti-
mate is even more favorable. Our experiments have shown t after
the removal of the bark the whole root be rasped and treated
directly for the manufacture of glucose, either by invers in with dias
tase or by treating with dilute sulphuric acid. In the latter not only
were the starch and sugar present in the root obtained as glucose, ut
also a considerable quantity of the digestible fiber.It i not a
extravagant statement, therefore, to suppose that fully 3per cent
of the weight of the fresh root could be obtained as commercial glu-
cose. This would give a yield per acre of 1.2 tons, or 2,400 p
These statements are made, of course, subject to the practical determi
nations of the manufacturer of glucose and starch from this plant.
Attempts have already been made in the manufacture of starch, but
of course the full development of this industry must awat the mves
llent of capital and the necessary adjustment of new mac y t
processes.

PLANS FOR A STARCH FACTORY USING POTATOES OR CASSAVA.
Through the kindness of Mr. Remmers, of De Land, e
plan of a strch factory suited for the working of either
potatoes is presented.
It would be advisable for all factories for this pu
upon somel such plan as is shown in the a mpanyingll
(ir. 17), since ), an arnrangeent of this kind the greatet




































Cross section of starch factory.




I.



































4, gater; 5, grater tank; 6, p mp from grater tank to sieve; 7, cylinder sieve; 8, shaking sieve;
9, starch settling tanks; 10, stirring tanks; 11, milk tanks; 12 ailk pump, 13, centrifugal tank ;
14, centrifugal; 15, starch elevator; 16, drying rooms; 17, pu tank; 18, outside settling tanks;
19, water from washer; 20, overflow to irrigation; (w, fresh water m).






44

of space is secured and the most convenient method of handlin the
product can be instituted. In point of fact, however, y of
potato-starch factories have been placed in buildings hich were
originally intended for other purposes so that the venience of
arrangement which is shown in the above plan is not always found.
Mr. B. Remmuers, of De Land, Fla., who has prepared this plan
made many valuable suggestions in regrd to the industry of a
facturing starch from cassava. According to the info ion which
he has given, the general course of procedure in the manufacture of
starch from cassava is the same as with potatoes. All the machinery
used in the potato-starch factories can be employed just as well in
the cassava factories, but the character of the rasps and blting cloths
must be adapted to the changed conditions dueto the differences
in the raw materials employed. There are many makers of otato-
starch apparatus in the United States, and so manufacturers prefer
one form of apparatus and some another. The same is true in regard
to the working processes; one person prefers the tabling of the starch
directly from the grater after sifting, while another prefers the set-
tling tanks, and still others a combination of both.
It is evident that the methods of work must be adapted to the con-
ditions which obtain and the character of the materials to be employed.
In some seasons both the cassava and potatoes yield better results than
in others, and only large experience can determine in the multitude of
details the best method to be pursued.
During the season of 1898-99 Mr. Remmers, with imperfect machin-
ery, secured a yield of 20 per cent of comnercial starch on the weight
of cassava root employed, and therefore with improved machinery and
improved cultivation it will not be difficult to bring this yield up to 25
per cent.
It is evident from a careful study of the problem in so far as it has
been worked out in practical experience, and theoretically considered,
that very little change in machinery and methods will be found neces-
sary in adapting a starch factory to the preparation of starch from
cassava. Since cassava will yield nearly double the percentae of
starch obtained from an equl weight of potatoes, it is evident that
in this plant the practical man will ind a promising source of profit in
those sections of our country where the soil and climate e suited to
the growth of cassava.
Large areas in Florida are well suited to cassava groing which so
far have not been found pofi e ffor other agricltural purposes.

PRESENT STATUS OF TIHE CASSAVA INDUSTY IN FLORIDA.
The factory of the Seminole Manufacturing Company, at D~e La
began operations in the sason of 1898-99. Dificulties dev d in
the application of macinery seted for the manufacureo




45

from cassava. While this factory will be idle during the season of
1899-190, the officials of the company are confident of the final suc-
cess of sava as a commercial source of starch, and propose to
continue operations at De Land, or in that vicinity.
The factory of the Planters' Manufacturing Company has been com-

that when changes are made in the pulping machinery to avoid diffi-
cties arising from the more fibrous nature of the cassava root, as
compared with potatoes, the success of the manufacture of cassava.
starch on a large scale will be assured. The nature of this difficulty
is not such that it will long baffle the efforts of our mechanical engi-
neers.
The McIntosh Cassava Company, a cooperative organization, pro-
poses to erect a factory at McIntosh for the crop of 1900-1901.
The interest of the people is thoroughly aroused and the value of
cassava as a stock food and as a source of starch is thoroughly appre-
ciated. The agricultural experiment station of Florida has been
especially active in conducting investigations in regard to the culture
and feeding value of the plant, and in bringing the results of these
experiments to the attention of the farmers of the State. A consider-
able prt of the station farm is devoted to the cassava experiments.








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INDEX.


A.
Page.
Smanufacture fron potatoes .................. ............. 26,27
erentation and distillation--........... 27
reparing potatoes .........-----..-- ... 26
stook County, Me., potato-starch idustry.---..-...-...................---------------. 5,12
Ae, ue of compounds as insecticides --.-----..------------....-- ----- 8
Sof aine-grown potatoes----------....... --- --------.......-----31, 32
varoot, analysis...... -------------- --......................------............--- 38
potatoes, analysis...................------...........-----......----------------..........------------.... 32

Smixture, use on potato vines----.-------.............--------------------- 9
sh gum, price-------------................................-----...--------........-------------------......... 22
C.
Cassava as an article of food.............-- -- --- -- -- --- -- -- --- -- -- --- 35
S composition -...........------------------.....--3.......-37
descriptions - -- - - - - - - - - - - - 34-35
flour, composition--.............................................- 36
growing ----....................................................- 39-42
dustyin Florida i-------. ------.----------..-----. ------ .. 44,45
manufacture of starch-.......................-----------------..----------------- 34-45
root and bark, composition-.----------------------------------- 36,39
tarch, micr pic fm -.......---------.------.----------.-------.. 3
percenta ge s-------..-----..-------.----..--- 37, 39,44
planor factory -.--.-- .- -----------.--..---------.. 42-44

ilrt~~ ,~t- S 431 A
ield o me tle t ...--.--.--------------------------........ 3 4
per acre -----------------.........................................--------....... 3641, 42

ei ation of potatoes, method ------------------------------...................................... 33,34
rin fromh .........................----....---------......----------.............- 25
rin, prices of various-------.----------.------------------ 21,22
F.
ry for manufacture of cassava starch, plans .--..-....------------.......-----....... ---.... 42-44
ries for starch from potatoes, number in Aroostook County, Me ----'-... 12
operated in Western States. - 6, 7
lizers, influence on of .....................----......--...... 7
used in growing oes, mposition...------..-..--.--..-..--. 6


ose, manufacture from cassava..................................... 42
K.
Sud in dying o........... ..... ......... 17,18
manner of treating the starch.................. 19,20
size .................................... 1------------------------------ 1

inery for cassava starch factor ....-..............-...-..--...-- ...... 44


composition of soil on which potatoes are grown--------------------- 8
grown potatoes, ah constituents---------.----- ----------------- 31,32
chemical composition -------------------------- 27,28
Sctories.........-----------------.......---.... 12
quantity of potatoes shipped per day --------------- 1
starch manufactured in 898-----------------12
ate of potash, effect on quality of potatoes ----------------------------- 7
N.
NewYork, annual production of potato starch---------------------------- 5
Nitrogen, influence on starch content of potatoes----""-"------------- -' 31
47






48

P.
Potash, muriate and sulphate, effect on quality of potatoes.------ 7
Potato dextrin, ue in print works .......................
starch as a source of dextrin....-.......... ........... 25
kin and price of potatoes for making ................. 11
minicroscopic appearance........................3233
price compared with indian-corn .starch ...........-- 24
used in the textile arts, etc ... .........
Potatoes, amount of starch produced in United States-----........
area under cultivation in Maine---------------....................---- 11
chemical composition ..............................------------------------ 27,28
cost of shipping -----------------------------.......-
for starch makig, kind and price ---.- w-.-----------.-- 1-----
growing..........--.......................................---------------------- 10
grown m Maine, description of samples ..---................. .... -2
m ethod of desiccation ------- ---- ----------w-------------------- 33--34
percentage of starch------------------------............................. 12
quantity shipped from Maine for seed .. .. ...------------- 9--1
use in ufacture of alcohol .........--........---... .- - ..--
yield ---------------------------------------------W------------- 11
Price of potato starch, ompared with indian-corn starch.........---------- 24



R.
Rasps used in reducing potatoes to pulp, description -.. .......... ...


Rotation of crops practiced in growing potatoes in Maine ....--...10-11
S.
Seed potatoes, method of keeping through the winter-..--..------------- 9
Sizing for print works, ethod of preparing with potato starch------ 22-23
inachnesandprocesses-....... ............----------------- ...... .. ---------
Soil for potato growing, coposition....-..-........................... --------------------
kind ited togrowth of potatoes...............
preparation for growing potatoes ..---------............--.--.............---------
suitable for growth of cassava ----------- .......------...-...--- .... 39-40
Starch, aiount iw potatoes as affected by fertiliers ..- .......... 7
barrelin and shipping ... ...... ........ ............... 20
contet in foreign-grown and home-growni pptatoes.......... ......' 1

factories, average capacity and cost--------------------.....---.... 12
nuber inr Aroostook Cunty,-- ------- ----
t op erated in Western States .------- .......
from cassava, method of obtaining and yield. -------------------. 37,38
potatoe, process f anufacture............................ -21
production in the United States ...--............. ..
in potatoes, percentagU I ----------------------..mu... ..... ...
anner of treating in the kiln .............................-----------------------
oe AtonMe.l--------------------------------------- 1. 78
nutm er in c ........ ........ ....... .... ;. .::



f separation -----------------------... ................... 14
s ,ettling ..................... ..................... 16
iwashin prf n......... ......---W ........................ 16
plans for factory fo making frm cassaa.........................

time reuir ed to dry -----------------------------...................




Warehuses, kind usedlfort itoring .potatoes -............................-.... 9
W ashing 1 0tatf t i ........................................................ 12-13
hing --o---------------- ----------------------- 1..

Wisconsin, annual production of potato starch ......... w-.---------------- 5
nature of soil en which potatoes are grown-............-.------- 6-
potato starch indumtry ......................................... 6
of~~~~~~ t inlunc on q~it of ................ + :+++:++
~~~~~~~~~~~~~~~~+ ++++ +++ +,,.~, iS ++++++ ++++ I + L IIE ? S~ .S
+ : ++
































44





UNIVERSITY OF FLORIDA

S 1262 0829 278I






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