The term “biota” is used throughout this text in lieu of “flora” as a general reference to bacteria. Flora refers to plant life. “Bacterial flora” dates back to the time when it was believed that bacteria were primitive plants. Since bacteria are not plants, “bacterial biota or microbiota” is preferred to flora. The major genera of bacteria, yeasts, and molds that are found in these products before spoilage are listed in Tables 4–1 and 4–2.
In general, the biota is reflective of the slaughtering and processing environments as noted above, with Gram-negative bacteria being predominant. Among Gram-positives, the enterococci are the biota most often found along with lactobacilli. Because of their ubiquity in meat-processing environments, a rather large number of mold genera may be expected, including Penicillium, Mucor.
microbial numbers. This may be illustrated by data obtained from a study of the bacteriology of several areas in the meat department of a large grocery store. The blade of the meat saw and the cutting block were swabbed immediately after they were cleaned on three different occasions with the following mean results: the saw blade had a total log10/in.2 count of 5.28, with 2.3 coliforms, 3.64 enterococci, 1.60 staphylococci, and 3.69 micrococci; the cutting block had a mean log10/in.2 count of 5.69, with 2.04 coliforms, 3.77 enterococci.
The high prevalence of enterococci in meats is illustrated by a study conducted in 2001–2002 on retail meats in the state if Iowa. Of 255 pork samples, 247 (97%) were positive for these organisms with 54% of isolates being Enterococcus faecalis and 38% E. faecium.84 Of 262 beef samples, all contained enterococci with 65% of isolates identified as E. faecium, 17% E. faecalis, and 14% E. hirae