COLIFORMS, ENTEROBACTERIACEAE AND TOTAL AEROBIC MESOPHILIC COUNTS IN SOME SELECTED MEAT PRODUCTS

A total of 40 meat products samples, 15 each from frozen burger and frozen sausage and 10 luncheon samples were purchased from local retail markets and super markets in Assiut city for determination of coliforms, Enterobacteriaceae and total aerobic mesophilic bacteria populations. The enumeration of coliforms and Enterobacteriaceae was performed by two methods, pour plate with an overlay and surface plating of violet red bile agar (VRBA) and violet red bile glucose agar (VRBG) respectively. The mean values of coliforms and Enterobacteriaceae counts by pour plate with overlay method were 16x10 and 11x10', 12x10 and 22x10 and 32x10 and 34x10 per gram examined frozen burger, frozen sausage and luncheon respectively, while they were 59x10 and 66x10 , 60x10 and 11x10° and 97x10 and 81x10 per gram examined sample by surface plating method respectively. It is evident that surface counts of both coli forms and Enterobacteriaceae were significantly higher than the overlay counts, where the pour plate with an overlay method is recommended in foods of animal origin with expected high Enterobc teriaceae level, while surface plating method is suitable in case of coliforms enumeration. The aerobic mesophilic bacteria mean counts were 66x 10, 27x10 and 11x10' per gram examined frozen burger, frozen sausage and luncheon samples respectively. The pres ence of numerous mesophilic bacteria often indicate contaminated raw materials or unsatisfactory processing from a sanitary point of view. Finally, it was found wide variation in microbiological quality of the examined meat products between different manufacturers.