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OCR for page 145
7
Consideration of Decision
(Action) To Be Taken When a
Criterion (Limit) Is Exceeded
In general, the decision taken when the limit in a microbiological cri-
terion is exceeded relates to the purpose for which the criterion was
established. Criterion limits are related to the acceptability of a raw ma-
terial, the adequacy of sanitation measures, the possibility of environ-
mental contamination, microbial buildup on equipment, or the acceptability
of finished product.
In most cases, knowledge that a limit has been exceeded comes "after
the fact." For example, the equipment was dirty at start-up; thermophilic
anaerobe levels built up in the starch-holding vat feeding the canning line;
lactobacilli that produce hydrogen peroxide reached excessive numbers
on a stainless steel table where canned hams were emptied prior to slicing,
thus posing the threat of discoloration if growth of these organisms con-
tinued in the finished product; or Salmonella was detected in the sifter
tailings from a milk dryer. In each instance the facts became known days
after the finished product was packaged, and in most cases after it had
left the processing plant. If microbiological criteria for monitoring con-
ditions such as these have been intelligently established, the retrospective
findings are of value and should trigger appropriate action.
Certain finished products must be held until their compliance with
established limits has been determined, e.g., infant formulas (Codex A1-
imentarius Commission, 19791. Embargoing finished product is costly and
cumbersome; alternative actions should be sought and used wherever pos-
sible. For example, with low-acid canned foods, reliance is placed upon
monitoring critical control points to give assurance that the process has
been properly applied (FDA, 1973; see also Chapter 9, Part J). Other
alternatives must be used with perishable foods. With fluid milk, for
145
OCR for page 146
146 EVALUATION OF THE ROLE OF MICROBIOLOGICAL CRITERIA
example, further sampling is undertaken when the standard plate count
exceeds the limit. If the problem persists and three out of the last five
analyses exceed the limit, a specified penalty provision is applied, one of
which is permit suspension (USPHS/FDA, 19781. If shucked oysters ex-
ceed the fecal coliform MPN limit, the oysters are accepted on the con-
dition that the state sanitation authority in the originating state makes
immediate investigation of the producer's plant and operations and submits
a report to the control agency in the market area. On the basis of this
report, the control agency in the market area will accept or reject further
shipments (USDHEW, 19651.
DECISION CATEGORIES
Evidence of Existence of a Direct Health Hazard
Whenever a product poses a direct hazard to health (see Chapter 4), an
implied standard (see Chapter 1, p. 52, note 3) exists and the product is
subject to seizure under the Food, Drug and Cosmetic Act (U. S. Congress,
19801. Examples would be the occurrence of Salmonella in dried milk
and botulinal toxin in smoked fish. The products involved are generally
voluntarily removed from the market by the processor, with the extent of
the recall and the form of publicity being commensurate with the degree
of hazard. If the processor or other responsible entity refuses voluntarily
to recall the product, then the Food and Drug Administration may take
legal action leading to seizure of the product. This is generally not nec-
essary when a product poses a direct hazard to health, as the processor
usually is willing to undertake a prompt recall.
The FDA may request recall of a product even if it does not pose a
direct health hazard, i.e., if the food is adulterated under Section 402 (a) (3)
and (4) of the Federal Food, Drug and Cosmetic Act (U.S. Congress,
19801. Examples are tree nuts contaminated with Escherichia cold and raw
shrimp containing salmonellae. It is held that E. cold in tree nuts is evi-
dence of the occurrence of filth (fecal material). Similarly, it is held that
salmonellae in raw shrimp constitute an added substance that would not
be present were the product prepared, packed, and held under sanitary
conditions. In neither case is it claimed that a direct health hazard exists.
Nevertheless, if recall is not voluntarily undertaken the FDA may take
legal action resulting in seizure.
Most states have even broader powers than the FDA. For example, a
state regulatory inspector may embargo a product without a court order;
most commonly this occurs within a processing plant, but it may extend
OCR for page 147
CONSIDERATION OF DECISION (ACTION)
147
beyond the processing facility into wholesale or retail channels. A USDA
inspector may similarly embargo a product without a court order.
The law provides alternatives to destruction, if the product can be
rendered safe for sale. Reprocessing of the product is permitted and should
be considered if the hazard can be eliminated, e.g., reconstitution and
repasteurization of dried milk or eggs containing salmonellae. The material
may be diverted into a product where the hazard is eliminated, e.g., dried
milk or eggs containing Salmonella used as ingredients in retorted foods
or dried egg yolk used as a component of mayonnaise.
In the case of products that are recalled or seized due to evidence of
filth, as in the case of E. cold in tree nuts, elimination of the indicator of
filth, ergo E. coli, by some physical or chemical treatment does not con-
stitute a reconditioning process satisfactory to the FDA. The filth as well
as. the indicator of its presence must be eliminated. Thus, a washing
procedure resulting in the elimination of E. cold would be satisfactory
whereas soaking the product in a chlorine solution would not be satisfac-
tor,v even if E. cold were eliminated by this treatment.
Frequently a product that is considered unfit for human consumption
is diverted into animal feeds. It is common for condemned or inedible
meat, poultry, dairy, and egg products to be used as ingredients in pet
foods. Inedible meat, poultry, and fish are rendered and the resultant high-
protein meals are used as components of animal feeds. These procedures
are justifiable, but not if the diversion ultimately results in perpetuation
of a problem in the human population. Blending of uncontaminated with
contaminated products in order to comply with established limits has
generally not been tolerated by regulatory authorities. In 1977, however,
large amounts of corn produced in the southeastern United States were
contaminated with aflatoxin. At that time, blending was permitted to bring
the concentration of aflatoxin to levels below the maximum permitted for
animal feed (FDA, 19781. A similar situation occurred with respect to the
1980 corn crop (FDA, 19811. It is to be expected, however, that blending
will continue in the future.
Destruction of the food is frequently the only alternative. Though
botulinal toxin is relatively heat labile, nothing short of destruction of ~
product containing this toxin is acceptable. Even though consumption of
a food containing Staphylococcus enterotoxin does not produce the dire
results associated with consumption of botulinal toxin, total destruction
of food containing this enterotoxin is indicated since it is heat stable.
In considering decisions concerning the fate of foods posing a direct
health hazard, careful consideration should be undertaken when alterna-
tives other than total destruction are contemplated.
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148 EVALUATION OF THE ROLE OF MICROBIOLOGICAL CRITERIA
Evidence That a Direct Health Hazard Could Develop
Though virtually any low-acid perishable food poses a potential health
hazard if mishandled, the potential for foodborne illness and the speed
with which it will develop are related to the numbers and types of con-
taminants present. Though small numbers of Staphylococcus aureus, Clos-
tridium pe~ringens and Bacillus cereus may be present in foods, they
pose no direct health hazard. If, however, mishandling occurs, growth of
any of these three organisms may lead to a direct health hazard. Large
numbers of B. cereus or S. aureus may produce enterotoxin in food before
it is consumed. Large numbers of C. perfringens, if present in food, may
lead to the in vivo production of enterotoxin in the consumer. Since small
numbers of S. aureus, C. perfringens, and B. cereus are frequently found
in food produced under Good Manufacturing Practices, criteria relating
to them usually recognize a tolerance, e.g., a few 100/g. Even if this
tolerance is greatly exceeded, e.g., levels between 10,000 and 100,000/
g are reached, a direct health hazard still may not exist. A hazard lies in
the possibility that further mishandling or previous growth not reflected
in such counts (preformed toxins) would create a direct health hazard (see
Chapter 41. If tests for preformed toxins are negative, then under controlled
circumstances foods of this type can be diverted to use under conditions
where proper food handling is assured, thereby avoiding the risk of de-
velopment of a direct hazard. Release to general distribution with all the
vagaries inherent therein is not advisable. If tests for preformed toxins are
positive, the food should be destroyed.
Indications That a Product Was Not
Produced Under Conditions Assuring Safety
Considerations relating to the above conditions have been discussed
previously with respect to the existing standards for fluid milk, water,
shellfish, and other commodities. For these products, standards based upon
the determination of indicator organisms have been established. The va-
lidity of these as measures of safe production practices has stood the test
of time. For example, shellfish and shellfish growing waters with excessive
numbers of coliforms and/or fecal coliforms pose the threat that pathogenic
microorganisms may also be present. Similar relationships between in-
dicator organisms and safety have not been widely applicable to other
foods. For example, indicator tests cannot be substituted for direct deter-
mination of Salmonella in dried foods and feeds (Silliker and Gabis, 19761.
Mesophilic anaerobic sporeforming bacteria in low-acid canned foods
have been used as indicators of unsafe processing conditions. Since Clos-
tridium botulinum is one of the most heat-resistant mesophilic sporeform
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CONSIDERATION OF DECISION (ACTION)
149
ing bacteria, the occurrence of mesophilic sporeforming bacteria in low-
acid canned foods purported to have received a botulinum cook suggests
underprocessing. Such bacterial examinations would be used in the in-
vestigation of a spoilage outbreak, but examination for mesophilic an-
aerobic sporeformers in sound containers should not be routinely
recommended.
Indications That a Raw Material May
Adversely Affect Shelf-life
With perishable raw materials such as raw meats, poultry, fish, and
liquid eggs, off-condition may be detected by sensory evaluation. The
consignment should be rejected when off-conditions are perceptible. The
same raw materials may contain high numbers of microorganisms and be
on the verge of spoilage (incipient spoilage) and yet show no overt evidence
in a sensory evaluation. Microbiological testing will detect borderline raw
materials of this type, but if sensory evaluation has been relied upon as
the acceptance criterion, then the information derived from the micro-
biological tests is of retrospective value, i.e., it becomes the basis for
decisions regarding suitability of suppliers. Frozen perishable raw products
may be held pending the determination of their acceptability prior to use,
in which case judgements may be made based upon either sensory eval-
uation or microbiological testing.
Nonperishable ingredients may be examined prior to use and, if they
fail to meet the limit in an established criterion, may be rejected as un-
suitable for their intended use. For example, sugar and starch destined to
be components of retorted canned foods may be rejected if they contain
excessive levels of thermophilic anaerobic sporeforming bacteria; spices
destined to be used in cooked sausages may be rejected if they contain
excessive levels of aerobic sporeforming bacteria (Silliker, 19631. Many
such criteria exist as components of purchase specifications.
As a rule, a raw material that is judged unsatisfactory for one purpose,
based upon failure to meet purchase specification limitations, may be quite
useful for another purpose. The presence of excessive levels of anaerobic
sporeforming bacteria in sugar may render it unsatisfactory as a raw in-
gredient for retorted canned products. This attribute is of no relevance,
however, if the same sugar is to be used as a sweetening agent in coffee
or baked goods.
Evidence That a Critical Control
Point Is Not Under Control
Evidence that a critical control point is not under control should trigger
immediate action. Such evidence may relate to a raw ingredient, to the
OCR for page 150
150 EVALUATION OF THE ROLE OF MICROBIOLOGICAL CRITERIA
microbiological condition of processing equipment, to the effectiveness
of a process, to the occurrence of undesirable microorganisms in a pro-
cessing environment, or to the microbiological condition of a finished
product. If it relates to a raw material, that ingredient should not be used.
If the raw material has been used, then its influence on the safety and
quality of the finished product must be assessed and appropriate measures
based upon the findings must be taken. If the critical control point relates
to equipment sanitation, the frequency and adequacy of cleaning proce-
dures must be reviewed. If failures in these areas influence finished product
safety or quality, appropriate decisions must be made with reference to
product distribution. If environmental contamination, as for example with
Salmonella, is indicated, then the source of such contamination must be
determined; furthermore, more intensive finished product testing may be
indicated. If failure of a processing step is indicated, the source of the
failure must be determined and eliminated. If the quality or safety of the
finished product is affected, appropriate steps must be taken with respect
to its distribution. If the problem relates to the microbiological condition
of the finished product, decisions must be made with respect to its dis-
tribution, and the reasons for the unsatisfactory condition of the finished
product must be determined. If the HACCP system has been properly
applied, the reasons for finished product failure should be evident from
monitoring results on critical control points.
Finally, it should be mentioned that where the Food and Drug Admin-
istration is responsible for assuring that processing plants operate under
Good Manufacturing Practices, failure of processors to control critical
points might be grounds for regulatory action, even though the limits for
these points were established by the processor.
REFERENCES
Codex Alimentarius Commission
1979 Microbiological specifications for foods for infants and children. Alinorm 79:13,
Appendix V.
FDA (Food and Drug Administration)
1973 Thermally processed low-acid foods packaged in hermetically sealed containers.
Part 128B (recodified as Part 113). Federal Register 38(16):2398-2410, Jan. 24.
1978 Aflatoxin-contaminated corn. Limited exemption from blending prohibition. Federal
Register 43(65): 14122- 14123. Apr. 4.
1981 Aflatoxin-contaminated corn; limited exemptions from prohibition of interstate ship-
ment and blending. Federal Register 46(15):7447-7449. Jan. 23.
Silliker, J. H.
1963 Total counts as indexes of food quality. Pp. 102-112 in Microbiological Quality of
Foods. L. W. Slanetz, C. O. Chichester, A. R. Gaufin, and Z. J. Ordal, eds. New
York: Academic Press.
OCR for page 151
CONSIDERATION OF DECISION (ACTION)
151
Silliker, J. H., and D. A. Gabis
1976 ICMSF Methods Studies. VII. Indicator tests as substitutes for direct testing of dried
foods and feeds for Salmonella. Can. J. Microbiol. 22:971-974.
USDHEW (U.S. Department of Health, Education and Welfare)
1965 Bacteriological criteria for shucked oysters at the wholesale market level. Appendix A
in National Shellfish Sanitation Program. Manual of Operations. PHS Pub. 33 (Re-
vised 1965). Washington D.C.: U.S. Government Printing Office.
USPHS/FDA (U.S. Public Health Service/Food and Drug Administration)
1978 Grade A Pasteurized Milk Ordinance. 1978 Recommendations. PHS/FDA Publication
229. Washington, D.C.: U.S. Government Printing Office.
U.S. Congress
1980 Federal Food, Drug and Cosmetic Act as amended. Washington, D.C.: U.S. Gov-
ernment Printing Office.
.
Representative terms from entire chapter:
health hazard
