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A total of 200 raw milk samples were randomly collected from different places in Mansoura city, Egypt during the period from May 2015 till December 2016. Collected samples were subjected for chemical and microbiological examination. Storchʼs test was applied for detection of heat treatment; Inhibitory test was directed for detection of any inhibitory substances and resulted in exclusion of 50 samples (25%). The mean pH, fat%, protein%, (SNF) %, lactose% and added water% were measured as 7.37%, 5.31%, 2.79%, 7.06%, 3.82% and 13.89%, respectively using lactoscan. The aerobic plate count, Enterobacteriaceae count and total Coliforms count were ranged from 3.4 ×10⁵ to 8.4 × 10⁹, 2 × 10⁵ to 3.6 × 10⁹ and 1×10⁵ to 6.3 × 10⁸cfu/ml, respectively. The mean count of yeast & mold and Staphylococcus spp. were 4 × 10⁵ and 2.1 × 10⁵ cfu/ml of milk samples produced in the study area. Besides, the mean count of S. aureus was 1.3 ×10⁶ cfu/ml. Serological examination was conducted to differentiate Enterobacteriaceae spp. PCR was applied to detect the nuc gene as a marker gene for S. aureus. All of milk samples examined were contaminated with S. aureus and Coliforms, most of samples were adulterated with added water.

Fifty random heat treated milk samples (25 each, pasteurized and UHT milk samples) were collected from different supermarkets in Mansoura City, Egypt. The collected samples were examined for quantitative detection of psychrotrophicBacillus cereus strains.The obtained results revealed that the incidence of psychrotrophicBacillus species was 19(76%) in pasteurized milk samples and 3(12%) in UHT milk samples and the total psychrotrophic Bacillus counts in pasteurized and UHT milk samples, were ranged from 1X 102 –5 X 102and zero– 1cells/ml with an average counts of 2.37 X102 and 1cells/ml, respectively. While the isolated strains were purified and identified as Bacillus cereus, B. circulans, B. coagulans, B. licheniformis, B. mycoides, B. pumilus, B. subtilis, B. sphaericus and B. thuringiensis.