ABSTRACT
Periodic sampling and determination of microbial counts is a matter of routine in most food processing plants. The samples can be of raw materials or ingredients, intermediate and finished products, and/or the water coming into or leaving the plant. The counts can be of the total microbial population, which is usually indicative of freshness as in meats and fish products, and/or the efficacy of sanitary measures aimed at reducing microbial growth, as in refrigerated raw milk or dried spices. Frequently, the counts are of groups or types of organisms that might have a specific impact on the food’s quality or safety. A notable example is the coliform count considered as a measure of a food’s or water’s contact with fecal material. However, counting other groups, such as total thermophiles or aerobes in baked snacks, yeast in products that contain fruit or fruit juice (including ice creams), and lactobacilli in dairy products, is also a common practice. When a direct safety risk is involved, the focus can be on a particular pathogen such as
Salmonella
in eggs and egg products,
Staphylococci
in refrigerated ground meats, or
listeria
in cured meat products. The same can be said about water, whether it is fresh from a well or
spring, in an open natural or man-made reservoir in a chlorination facility before its delivery, or in a treatment plant upon its arrival and discharge. Again, the counts can be of the total microbial population, coliforms, or specific pathogens, which need not be exclusively bacterial. The same applies to water used for recreation, such as in beaches and swimming pools; again, the total count might be indicative of the overall sanitary conditions at the site, the coliform or
E. coli
count of the degree of the water’s fecal contamination, and the counts of specific pathogens (including viruses and protozoa) of the water’s safety for the public’s use.
