5771
REUSE OF FERMENTATION
BRINES IN THE
CUCUMBER PICKLING INDUSTRY
EXECUTIVE SUMMARY
U.S. ENVIRONMENTAL PROTECTION AGENCY
INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY
-CINCINNATI-
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DISCLAIMER
This Executive Summary has been reviewed by the Industrial
Environmental Research Laboratory-Cincinnati, U.S. Environmental
Protection Agency, and approved for publication. Approval does
not signify that the contents necessarily reflect the views and
policies of the U.S. Environmental Protection Agency, nor does
mention of trade names or commercial products constitute endorse-
ment or recommendation for use.
The Executive Summary is published with the intent of pro-
viding quick and concise information on the results and findings
of this project. In this context, review has been kept to a mini
mum. The Final Report has been published under the same title
as an ORD Series 2 report (600/2-78-207).
ACKNOWLEDGEMENT
This Executive Summary Report was prepared by SCS Engineers,
Long Beach, California, under Contract No. 68-03-2578. The EPA
Project Officer of the original grant was Harold W. Thompson.
For further information on the project, contact the Food and Wood
Products Branch, Industrial Pollution Control Division, Industrial
Environmental Research Laboratory, Cincinnati, Ohio.
11
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REUSE OF FERMENTATION BRINES IN
THE CUCUMBER PICKLING INDUSTRY
- EXECUTIVE SUMMARY -
SIGNIFICANCE
The project evaluated on a commercial scale the technological
and economic feasibility of recycling spent cucumber fermentation
brine. Two brine treatment procedures, heat treatment and chemi-
cal treatment, were used. The results showed that brine recycling
was practical. Either brine treatment procedure resulted in salt
stocks which were equivalent in quality to control cucumbers.
An economic evaluation of the recycling procedures showed a
small net savings for the heat treatment procedure and a small
net cost for chemical treatment. Selection of the process for a
particular plant will depend upon the local conditions.
PROJECT OBJECTIVES AND BACKGROUND
The commercial, technological, and economic feasibility of
recycling spent cucumber fermentation brine by heat and chemical
treatments were evaluated. Chemical treatment of spent brine was
performed by the addition of Food Grade sodium hydroxide (NaOH)
pellets to spent brine tanks to raise the pH to 11 or greater.
A resulting precipitate was allowed to settle and was discarded.
After settling, the clear brine was pumped into a clean tank,
adjusted to pH 4.5 to 4.7 with 300 grain vinegar, and held until
used in subsequent fermentation processes as a cover brine. In
the heat treatment process, spent brine was heated to 90.5°C
(195°F) and held at its original pH (3.2 to 3.5). Prior to use
as a cover brine, the pH was raised to 4.5 with NaOH pellets.
To evaluate the effects of brine recyclinq it was necessary
to compare the salt stock (fermented cucumbers] and brines from
fermentations with recycled brines to control fermentations in
which green stock cucumbers were covered with freshly prepared
salt solutions. Control fermentations were performed according
to normal commercial brining procedures. Beginning in 1975,
experimental full-scale fermentation brines were reclaimed and
reused through three complete fermentation cycles for both the
heat and the chemical treatments. Figure 1 illustrates the exper-
imental design used in evaluating brine recycling.
1
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Fresh Salt Brine
I
1974 1st Cycle Fermentation
1st Cycle Spent Brine
Heat Treatment
(Pasteurization)
I
1975 2nd Cycle
Fermentation
I
2nd Cycle
Spent Brine
I
Pasteurizati on
Treatment
t
1976 3rd Cycle
Fermentation
I
3rd Cycle
Spent Brine
Chemi cal
Treatment
I
1975 2nd Cycle
Fermentati on
2nd Cycle
Spent Brine
I
Chemical
Treatment
I
1976 -3rd Cycle
Fermentation
\
3rd Cycle
Spent Brine
1975 Control
Fermentation
I
1st Cycle
Spent Brine
1976 Control
Fermentation
I
1st Cycle
Spent Brine
Figure 1. General design of the commercial evaluation
of brine recycling.
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In addition to the feasibility studies, separate experiments
were conducted to evaluate potential difficulties in using recy-
cled brine. These were:
• Evaluation of pesticide buildup with multiple use of
brine
t Determination of thermal and pH stability of fungal pec-
tinases (softening enzymes) which are most likely to occur
in fermentation brines
• Measurement of lysinoalanine (an amino acid reported to
be toxic to laboratory test animals) in chemically treated
brine.
These experiments were performed with separate spent brine
solutions from those used in the feasibility studies. The same
procedures for heat or chemical treatment, however, were applied
in these additional studies.
CONCLUSIONS
The following conclusions were made regarding the feasibility
of brine recycling :
• Brine recycling is an effective procedure for reduction
of waste in the manufacture of salt-stock pickles.
t Both the heat and chemical treatments for spent brine are
practical for use in current commercial tank yard opera-
ti ons.
t Heating spent brine for 30 sec at 90.5°C (195°F) will
assure at least 99.98 percent destruction of pectinases
from fungi which were found to be common on cucumber fruits
and flowers.
• Raising the pH of >72°F spent brine to 11.2 or higher for
at least 37 hr wilT decrease Penicillium janthi nel lum. pec-
tinase activity in spent brines to <1 plfrcent of its ini-
tial activity, a treatment considered adequate for brine
recycli ng.
t Salt-stock cucumbers produced from fermentation using
recycled brines are equivalent to control salt stock in
bloater losses, texture, and flavor. Consumers have not
detected any significant differences in products prepared
from salt stock fermented in recycled brine.
• No significant accumulations of metals or pesticides
occur as a result of brine recycling.
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t The results show that brine can be reused for at least
three fermentation cycles on a commercial basis. There
were no indications of adverse effects of recycling on
salt-stock quality or buildup of toxic constituents.
This suggests that brine can continue to be reused beyond
three cycles.
a Under the conditions of this project, heat treatment of
brine resulted in a small net savings while there was a
small net cost for chemical treatment. The relative eco-
nomics of these two recycling procedures may vary with
individual circumstances. However, the use of recycling
is an economically feasible means of reducing the waste
from tank yard operations.
A summary of these findings is provided in Table 1.
Characteristics of Recycled Brjnes
Heat treatment of the first cycle brine caused few changes.
The pH and titratable acidity were increased and decreased, res-
pectively, as the result of NaOH addition after heat treatment.
Aluminum levels increased almost twofold.
Chemical treatment caused a number of changes in the brines.
The pH and titratable acidity changed as expected. Reducing
sugars declined under the alkaline conditions. Formation and
removal of a p'recipitate reduced the suspended solids. The pre-
cipitate consisted primarily of mineral material. Aluminum was
the only mineral component to show an increase. BOD and COD
increased as a result of vinegar addition for pH adjustment.
Heat treatment of the second dycle brine resulted in no sig-
nificant change in brine composition except for an increase in
pH and decrease in titratable acidity. Chemical treatment (in
1975 and 1976) caused significant changes in the same components
and in the same directions as noted above with the exception of
BOD and Fe. In those two instances, the increase in BOD and the
decrease in Fe were not significant.
Comparison of the heat-treated first- and second-cycle brines
showed an increase in BOD from 9,700 mg/l to 14,000 mg/Jl and COD
from 12,800 mg/£ to 19,300 mg/£. In addition, there were small
increases in the concentration of P, Ca, and Mg. For chemical
treatment this first- and second-cycle comparison showed that BOD
and COD increased. Though the levels of. P, Ca, and Mg were lower
in treated brines, the levels in 1975 were actually slightly
higher than in 1976. This may have been a result of more effi-
cient removal of precipitate in 1976.
Third-cycle brines were removed from cucumber fermentation
tanks after the third-cycle fermentation. The concentrations of
4
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minerals were similar to the concentration before treatment of the
first- and second-cycle brines. Since the project was concluded
at the end of the third cycle of fermentation, the third-cycle
brines were not treated.
The results of these experiments showed that heat treatment
had no effect upon the brine constituents, except for aluminum
and the pH and titratable acidity, which were intentionally
altered. Chemical treatment resulted in a decline in most of the
mineral constituents of brine. The BOD and COD were increased as
a result of vinegar addition. Aluminum levels increased after
completion of brine treatment with both the chemical and heat
techniques. It may be that the food grade NaOH, which was used
in both procedures, contained some aluminum as an impurity.
Commercial Evaluation of Brine Recycling
Cucumbers fermented in recycled brine were judged to have
normal texture, color, and odor. Pressure test evaluation of the
desalted stock from second-cycle fermentations showed no signifi-
cant differences in the stock from recycled brines.
Taste panel evaluations for texture, flavor, and overall
quality done on hamburger dill chips showed no significant differ-
ences between control salt stock and from salt stock fermented in
either heat-treated or chemically-treated recycled brine.
Based upon commercial experience, there does not appear to
be any significant deterioration or improvement in the quality
of products obtained from fermentation in recycled brine. There
have been no complaints from either insititutional or individual
consumers of these products which have been related to use of
recycled brine.
Technological Evaluation of Bring Recycling
The data on the commercial quality of salt stock, on the com-
position of spent brines before and after treatment, on the course
of fermentation, and on the mineral components of cucumbers before
and after desalting led to the following conclusions regarding the
technological aspects of brine recycling.
• Major changes in tank yard practice were not required for
bri ne recycling.
• Fermentations proceeded normally. The same criteria used
to judge completion of fresh brine fermentations could be
used to judge fermentation with recycled brine.
• Treated brine which contained 12.5 percent Nad could be
used without dilution as a cover brine. This yielded salt
stock equivalent in quality to control tanks.
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• Changes in brine or cucumber composition as a result of
recycling were small. There were no significant buildups
of toxic elements in brines or cucumbers which would indi-
cate that recycling should not be done or that the number
of brining cycles would need to be limited.
• From a technical point of view, recycling the brine was
practical and resulted in final products which were com-
mercially equivalent to the controls.
Economic Evaluation of Brine Recycling
Brine treatment costs
shown in Table 2:
for chemical and heat treatment are
TABLE 2. ECONOMIC EVALUATION OF CHEMICAL AND
HEAT TREATMENT (COSTS PER 1,000 GAL)
Total Treatment Costs
Total Savings from
Recycling
Net Savings
Net Costs
Heat Treatment
1975 1976
$ 6.37 $ 7.05
19.21
12.84
0
19.21
12.16
0
Chemical Treatment
1975 1976
$21.29 $23.48
19.21
0
2.08
19.21
0
4.27
Treatment costs for heat treatment were considerably lower than
for chemical treatment. Although initial capital investment for
a heat exchanger is high, estimates of the savings realized .over
a 5-yr period using heat treatment indicated that the heat treat-
ment would be the procedure of choice.
In summary, the study indicated that either chemical or heat
treatment can be utilized without making the cost of brine recy-
cling prohibitive. It appears that in many situations, the heat
treatment procedure would be economically advantageous. However,
an analysis must be made for each particular situation considering
local economic and physical conditions.
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RESULTS OF SPECIAL STUDIES
Pesticide Distribution in Brine Recycling
Cucumbers raised on selected plots of land were treated with
selected pesticides (chloronab, PCNB, PCA, Parathion, Paraoxon,
Bravo, Dacthal , Difoltan, Endosulfan I, Endosulfan II, Endosulfan
$04, and Carbaryl) at twice the recommended dosage and harvested
at one-half the harvest interval recommended by EPA. Multiple
reuse of recycled brine for the fermentation of these test cucum-
bers was evaluated for pesticide buildup.
Of selected pesticides, carbaryl was the only one which was
accumulated in significant amounts in the brining solution. When
green stock cucumbers low in pesticide residues were brined in
tanks with higher pesticide concentrations than control brines,
pesticide concentrations increased slightly in the brined cucum-
bers over the raw pesticide concentration. At the same time, as
the raw cucumbers were absorbing the pesticides, concentrations
in the initially elevated brines decreased to trace amounts.
Pectinase Inactivation
The possibility for introduction of pectinases into spent
brines, either from the previous fermentation or during periods
of brine storage, was a major concern in the development of recy-
cling procedures. If these enzymes were not properly controlled,
serious softening of cucumber salt stock could result.
Investigations were performed into the thermal stability of
fungal pectinase enzymes under conditions which might occur during
brine treatment. Heating at 79.4°C (175°F) for 30 sec was found
to be sufficient to inactivate pectinase enzymes from Penicil1ium
Jan thine!Turn, the most heat stable pectinase tested. Studies on
the effects of differing pH levels at 22°C (72°F) on Penicillurn
janthinellum pectinase activity showed that pH should be raised
to 11.2 or higher and held for at least 37 hr to assure 99 percent
inactivation of pectinases.
It was not possible to evaluate the effect of heat and chemi-
cal treatments on the inactivation of pectinase as they occur in
commercial brines since analysis of spent brines showed no meas-
urable pectinase activity.
Lysinoalanine
Since it was known that base treatment of protein could lead
to the formation of lysinoalanine (an amino acid that, when in
the free state, has been shown to be toxic to rats), experiments
were performed to determine whether lysinoalanine was formed dur-
ing base treatment of spent brine. Results indicated that signi-
ficant amounts of lysinoalanine were not formed as a consequence
8
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of base treatment. The levels in pickle brine appeared to be
considerably lower than levels reported in processed foods con-
taining significant levels of protein.
RECOMMENDATIONS
As a result of this study, the following recommendations
were made:
• Brine recycling should be adopted by the processed cucum-
ber pickling industry as a means to reduce wastes.
• Both heat and chemical treatments of the spent brine are
effective from a technical viewpoint. Selection of a
procedure can be based upon economic considerations and
upon the relative compatabi1ity of the procedures with
each particular tank yard operation.
• Care should be taken to ensure proper design of a recy-
cling system, proper training of operating personnel, and
proper supervision of the procedure, since improper recy-
cling techniques hold the potential for significant eco-
nomic losses.
t Undertake an evaluation of calcium hydroxide as a partial
or total replacement of sodium hydroxide in the chemical
treatment procedure.
« Evaluate the need to remove the precipitate formed during
chemical treatment.
t Efforts should be made to reduce tank leakage and overflow,
since significant brine losses occur from these sources.
• A major effort is needed to develop salt-stock storage
technology, which will allow reduction in the salt levels
maintained in brining tanks, since wastes generated in
the desalting operation are second only to spent brine as
a source of waste in tank yard operations.
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1 REPORT NO 2.
4. TITLE ANDSUBTITLE
REUSE OF FERMENTATION BRINES IN THE CUCUMBER PICKLING
INDUSTRY - EXECUTIVE SUMMARY
7. AUTHOR(S)
R.F. McFeeters, W. Coon, M.P. Palnitkar, M. Velting,
and N. Fahringer
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Pickle Packers International
108 East Main Street
P.O. Box 31
St. Charles, Illinois 60174
12. SPONSORING AGENCY NAME AND ADDRESS
3. RECIPIENT'S ACCESSION NO.
5. REPORT DATE
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
1BB610
11. CONTRACT/GRANT NO.
S-803825
13. TYPE OF REPORT AND PERIOD COVERED
Final Report (5/75 - 12/77)
14. SPONSORING AGENCY CODE
EPA/600/12
15. SUPPLEMENTARY NOTES
The final report for this project, under the same title, is to be published as an
ORD Series 2 report.
16. ABSTRACT
The project evaluated on a commercial scale the technological and economic
feasibility of recycling spent cucumber fermentation brine. Two brine treatment
procedures: heat treatment and chemical treatment, were used. The results showed
that brine recycling was practical on a commercial scale. Either brine treatment
procedure resulted in salt stock, which were equivalent in quality to control
cucumbers.
Studies were conducted to determine the adequacy of the brine treatment pro-
cedures employed. The data confirmed that a heat treatment of 175°F for 30 sec
was sufficient to assure inactivation of pectinases from molds found to be common
on cucumber fruits and flowers. For effective chemical treatment, a brine temper-
ature of 72°F or higher was required. In addition, the pH had to be maintained at
11.0 or higher for at least 36 hr to assure 99 percent inactivation of pectinases
from the molds which were investigated.
An economic evaluation of the recycling procedures showed a small net savings
for the heat treatment procedure and a small net cost for chemical treatment. Selec-
tion of the process for a particular plant will depend upon the local conditions.
17. KEY WORDS AND DOCUMENT ANALYSIS
a. DESCRIPTORS
Food Processing
Vegetables
Brines
Circulation
Economic Analysis
Treatment
18. DISTRIBUTION STATEMENT
Release to Public
b. IDENTIFIERS/OPEN ENDED TERMS
Cucumber Brine
Recycle
Commercial Scale
19 SECURITY £L&SS, (This Report!
Unclassified
20. SECURITY CLASS (This page)
Unclassified
c. COSATI Field/Group
68D
21. NO. OF PAGES
12
22. PRICE
EPA Form 2220-1 (Rev. 4-77)
PREVIOUS EDITION IS OBSOLETE
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