Group Title: Citrus Station mimeo report - Florida Citrus Experiment Station ; CES 67-9
Title: Modifications to state test room extractors for obtaining juice yields of less than 100 percent
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 Material Information
Title: Modifications to state test room extractors for obtaining juice yields of less than 100 percent
Series Title: Citrus Station mimeo report
Physical Description: 5 leaves : ; 28 cm.
Language: English
Creator: Blair, James G
Citrus Experiment Station (Lake Alfred, Fla.)
Florida Citrus Commission
Publisher: Citrus Experiment Station :
Florida Citrus Commission
Place of Publication: Lake Alfred FL
Publication Date: 1966?
Subject: Orange juice -- Processing -- Florida   ( lcsh )
Orange juice -- Yields -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
non-fiction   ( marcgt )
Statement of Responsibility: James G. Blair.
General Note: Caption title.
General Note: "400-10/4/66-JGB."
 Record Information
Bibliographic ID: UF00072445
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 76751796

Full Text

Florida Citrus Commission and
Citrus Experiment Station CES 67-9
Lake Alfred, Florida. 400-10/4/66- JGB

Modifications to State Test Room Extractors for Obtaining Juice Yields
of Less Than 100 Percent1

James G. Blair
Florida Citrus Commission
Lake Alfred, Florida


What happened to pulp wash? The quality consciousness about frozen concen-
trated orange juice, that reached a climax last season, eliminated pulp wash and
the so-called "tight squeeze" in the production of this product. To compensate
the processor for the loss in yield resulting from this change, the growers
agreed to give up an equal amount in their return. There are many ways the
growers return could be adjusted but, in general, many thought it should be done
at the State Test Room. In theory, this is a good place to adjust the yield,.
but in practice it is not too simple.

Why isn't such an adjustment easy to accomplish? The main reason is the
complexity of the problem of measuring juice yield from plant to plant which
requires reproducibility of results regardless of fruit size, variety, and
condition. This problem has been with this industry since the measurement of
pounds-solids was introduced. In 1961, it was recognized by the industry as
serious. The USDA was therefore requested to make a study and submit a report
of their findings, together with any recommendations they might have for improv-
ing the methods used for determining pounds-solids. The survey team's report
was accepted and the Pounds-Solids Project was initiated. It was organized as
a cooperative project between the Florida Citrus Commission, Florida Department
of Agriculture, Florida Agricultural Experiment Stations and United States
Department of Agriculture.

The USDA report defined the problem as having three main categories: Namely,
sampling, extraction, and Brix determination. While all three are equally im-
portant, it was generally agreed that the extraction problem was the most complex.

The development of an improved test room extractor has been in process for
about twenty years and during this time progress has been made. For example, it has
been only during the last couple of years that the test room extractors remained
at one basic setting for the entire season. Previously, it had been necessary
to make major adjustments during the season to keep the results uniform. The
annual theoretical yield obtained by the State Test Room extractors as compared
to the actual State average of the single-strength pack-out was within 2% for
the 1965-66 season. It is at this point of development that we are now faced
with realigning these extractors to yield somewhere around 5% less. This should
not be any more difficult than the development to the present status and, if
time permitted, could readily and accurately be accomplished. Without the
benefit of the necessary time to make extended comparisons against actual plant
yields, a control that will accurately represent 100% yield is necessary.

1Cooperative project between the Florida Citrus Commission, Florida
Department of Agriculture, Florida Agricultural Experiment Stations and United
States Department of Agriculture.

All right, what can be used as a control? Not the hand ream method,
because it is too slow and affected too much by human variances even though it
is the only method presently recognized by the State. How about the present
Brown 2701 machine? About three years ago, a very thorough comparison was made
between the Brown 2700 and the hand ream method and a complete statistical
analysis made of the results on early maturing grapefruit in particular. It was
concluded from this report that this machine was at least as good or better than
the hand ream method. Since that time, however, very little progress has been
made toward further developing this machine as a standard test machine, It was
suggested that such a development program be instituted and a trailer equipped
as a mobile test laboratory was purchase for this purpose. The idea was never
put to use because of resistance from certain sources to the thought of a check
machine. After that, the 2700 extractor was modified and became the 2701. Ad-
justments and readjustments were made using it as a gauge for comparing the
yields from the Brown 2800, 2900, 3100, and 3300 model extractors. Last season
the rotating head was redesigned to eliminate a slight size bias but the manu-
facturer preferred to retain the 2701 model number. Incorporated in this last
modification were the settings required to make the performance similar to the
original 2700 extractor. During the interim period, confidence in the machine
and the opportunity for accumulating reliable experimental data were lost. So,
where do we go from here? Well, research work has been in progress on develop-
ing an experimental laboratory method to measure juice yield since 1961 and
recent results have been encouraging. To establish a base, using 'Valencias',
was fairly simple. A FMC extractor and finisher with settings to simulate an
average commercial operation were used. If the industry is satisfied with the
juice obtained from this type of operation and it meets the requirements of
existing regulations, it would represent a satisfactory base. The experimental
laboratory method, using the Brown 2701, was set to duplicate the yields obtained
from an average commercial operation. Some results of such tests are shown in
Table 1.

Table 1. Comparison of yields between experimental laboratory method
and FMC average commercial operation
Yields based on fruit weight-%
Extractor Date 5/31 6/1 6/2 6/3 6/8 6/9
FMC commercial 59.94 63.85 63.88 63.83 64.15 63.84
Brown 2701 60.98 63.64 63.72 64.07 65.02 63.82

Unfortunately, time has not permitted the establishment of research data on the
same relationship for early and midseason fruit. Therefore, some gamble would
be involved in using this method without first proving it reliable through

In order to give further time for the research on this problem the USDA and
the Florida Department of Agriculture agreed to change their juice yield tables
to reflect a 5% reduction. All certificates that were issued by the Inspection
Service last season showed a juice yield of 5% less than that obtained by the
test room extractors.
Florida Citrus Commission and
Florida Citrus Experiment Station,
Lake Alfred, Florida.
400-10/4/66 JGB

Any readjusting of the test machines to reflect this lower yield will not
change the relative return to the grower from what it was last year. It will
only eliminate the factor now used by the Inspection Service and legally, at
least, this may be a more sound approach.


Last season the question of the 95% setting was discussed as a possible
addition to the pounds-solids research program. The introduction of this
added variable was discouraged due to the pressure for answers to the existing
problems. Measuring machine performances against one another for reproduci-
bility, size, and variety bias is one thing, but to do all this at an unknown
level (95%) is quite another thing. First, it is necessary to establish a
100% yield figure and, as previously mentioned, an accurate experimental
laboratory method has not as yet been found. The performance of the Brown 400
and the FMC 091 over the entire season gives an average yield of just over 100%,
but on any one test or even any one day, the results from either of these
machines would not be satisfactory. If they were, there would be no reason for
spending citrus research dollars on this phase of the pounds-solids problem.

What is necessary in adjusting the test room extractors to obtain 95% of
their theoretical 100% yield? First the Brown 400; the manufacturer realis-
tically states that he cannot guarantee reliability beyond a 3% reduction. In
order to obtain this, it is necessary to increase the clearance between the
cups and the reamers of the extractor and, also, reduce the air pressure on the
finisher discharge control. There are several more adjustments that could be
made but they are more in the nature of modifications.

The FMC 091 extractor has several adjustable features. They are orifice
tubes, strainer screens, and beam settings.

Some early tests on oranges were made on these machines in which each
manufacturer assumed the standard setting on his machine represented the 100%
level. Reduced yields from these levels were attempted and the results are
shown in Tables 2 and 3. The work was done early in the season prior to the
time the regular pounds-solids test program started. As you will notice, the
FMC tests were run at both the Florida Citrus Canners Cooperative as well as
the Citrus Experiment Station. Various settings of the machine were made with-
in the limits of available interchangeable parts. Results were not very
encouraging. It was immediately apparent that loosening the adjustments
aggravated the difference between the seedless and seedy varieties. Other
combinations might have been tried but the necessary parts and time for such
tests were just not available.

The Brown 400 extractor was tested at field locations only, but the
results were no more encouraging than those from the FMC extractor tests.

The Brown 3300 extractor has several more adjustable features than the
400 extractor. They are: clearance, which is the space between the rotating
disc and the screen during the period of extraction; the dwell time which is
the period of extraction; the air pressure which regulates the amount of

Florida Citrus Commission and
Florida Citrus Experiment Station,
Lake Alfred, Florida.
400-10/4/66 JGB

pressure the rotating disc applies to each half of fruit; the perforations in
the screen, both size and number; and the speed of the rotating head. In
addition, the material on the rotating disc and the shape of this material can
be changed but this is considered more than an adjustment.

The Inspection Service was very interested in what the new Brown 3300
extractor would do on a reduced yield setting so they arrange to experiment
with this extractor at a time when it was not being used in the pounds-solids
test program. The afternoon of January 24, 1966 was agreed upon and they, in
cooperation with the Brown Citrus Machinery Corporation ran a series of tests.
The results are shown in Table 4.

As with the other extractors the Brown 3300 so-called standard setting was
used as 100% and an attempt to back off from this through various adjustments
was made. The results on the seedy variety look good but the last half of the
tests on the seedless variety are out of line.

No further work was done on measuring reduced yields until the Florida
Canners Association approved a recommended test program developed by the
Inspection Service. This program encompasses a much broader field than the
one approved by the industry in 1961. The main sources of difference is in
the testing of grapefruit and reduced yields. The amount of testing was also
extensively increased requiring the temporary assignment to the pounds-solids
project of considerably more man power.

Although this program was approved on May 10, 1966, it was not until the
25th that extractors and sufficient man power were available to get started.
The procurement of fruit that had no freeze damage or natural dryness was
most difficult but was finally worked out through the cooperation of the Pasco
Packing Company. The first few days of the program were used for trying out
various adjustments. Size relationship was a factor in these earlier tests but
the main consideration was to find a setting that would produce 95%. Finally,
on June 3, 6, and 7, test results started to show promise. After an agreement
was reached that the right adjustments had been found, a two-day series of
tests, using random fruit sizes, were run to check out the extractors.
Fortunately, the results were considered satisfactory for the only available
fruit supply was nearly depleted. The figures shown in Table 5 are an indi-
cation of results for two different fruit size categories for the last 5 day
period of operation.

The FMC 091 standard extractor yield was accepted as 100%. The settings
for this extractor consisted of an .025 strainer tube, 3.95 sq. inches of open
area, a 7/16 inch bell mouth orifice tube, and 1/8 inch beam setting. Changes
from these settings were initiated resulting in the FMC 091 BX type designed to
improve the operation of the air cylinders. The settings used for 95% yield
consisted of an .020 strainer tube, 3.40 sq. inches of open area, 20 psi air
pressure, a 1 3/16 inch orifice tube, and 1/8 inch beam setting.

Settings for the Brown 3300 extractor for obtaining 100% yield consisted
of a 1.8 second dwell time, head design "A", a clearance of .065 inches, 40
psi air pressure, and the use of partial wipers. The 95% extractor settings for
the Brown 3300 used the "B" head design with a clearance of .070 inches, a 30
psi pressure, and the use of full wipers.

Florida Citrus Commission and
Florida Citrus Experiment Station,
Lake Alfred, Florida.
400-10/4/66 JGB

Yields from the FMC 091BX ranged from 94.80 to 96.88% for all tests during
the 5 days; the overall average was 95.51%.

When the Brown 3300 with the "A" head was used over the 5 day period, the
yields ranged from 98.05 to 101.87%; with the "B" head, the range was 92.56 to
96.59%. The overall averages for the Brown 3300 with the "A" and "B" heads
were 101.10% and 94.95%, respectively.

Florida Citrus Commission and
Florida Citrus Experiment Station,
Lake Alfred, Florida.
400-10/4/66 JGB

Table 2. Reduced yield tests using FMC 091 test extractor
Extractor settings 3" cup Percent yield
Strainer FCCC CES
Beam tube Orifice tube Seedless Seedy Seedless Seedy
1/8" .025 7/16" Bellmouth (st'd) 100.00 100.00 100.00 100.00
1/8" .025 5/8" Bore 95.60 97.00 97.80 99.30
1/8" .025 1/2" Restrictor in 5/8" bore 98.30 99.40 99.70 99.80
1/8" .025 9/16" Restrictor in 5/8" bore - 98.66 98.82
1/8" .020 7/16" Bell mouth 88.90 92.90 93.10 94.30
3/4" .020 7/16" Bell mouth 93.20 94.90 95.20 98.00

T ?1 eue

yield tests using Brown 400 test extractor

Florida Citrus Commission and
Florida Citrus Experiment Station,
Lake Alfred, Florida.
400-10/4/66 JGB

Percent yield
Air Reamer settings
pressure 3/32 inch 1/8 inch
Kraft Adams Adams
Seedless Seedless Seedy Seedless Seedy

11 100.00 100.00 - -
9 98.90 99.60 100.20 99.10
8 1/2 100.00 - - -
7 99.13 95.20 99.40 99.80 99.00
6 98.73 98.00 99.30 - -
5 98.01 - 95.30 97.30

Table 4. Reduced yield tests

Standard setting was .040 clearance, 2 seconds
time, 40 psi pressure, .027 screen mesh and 85

rpm head

Table 5. Reduced yield tests showing comparison of extractors on the
basis of yield from the FMC 091, used as a standard of 100%
FMC 091 FMC Brown 3300
Extractor Standard 091 BX "A" Head "B" Head

Percent yield Fruit size 163's _
6-3-66 100.00 94.80 95.31 98.33 99.98 92.97 93.74
6-6-66 100.00 95.09 94.98 98.05 99.14 92.56 94.28
6-7-66 100.00 96.88 94.90 101.87 98.89 96.10 94.51
Avg. Values 100.00 95.59 95.06 99.42 99.34 93.88 94.18

Percent yield Fruit sizes 125's through 360's
6-8-66 100.00 95.94 95.42 100.62 100.60 94.80 95.80
6-9-66 100.00 95.97 95.41 101.44 100.59 96.59 96.39
Avg. Values 100.00 95.96 95.44 101.03 100.60 95.70 96.10

Florida Citrus
Florida Citrus

Commission and
Experiment Station,

Lake Alfred, Florida.
400-10/4/66 JGB

Extractor settings Percent yield
changes from Seedless Seedy
standard1 fruit fruit
Standard 100.00 100.00
Head @ 42.5 rpm 98.10 98.20
Head @ 42.5 rpm,
pressure @ 35 psi 99.00 98.40
Head @ 42.5 rpm, pressure
@ 35 psi, .060 clearance 91.50 96.20
.020 screen 91.20 96.40
Return to standard 96.20 99.20

using Brown 3300 test

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