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One hundred and fifty-two commercially-produced yogurts were subjected to microbiological examination for lactobacillus/streptococcus ratio, staphylococcus count, coliform count, enterococcus count, yeast and mold count, and psychrotrophic count. These yogurts were produced by 13 different manufacturers and sold in Ontario. The desired 1:1 ratio of lactobacillus to streptococcus was found in 15.1% of the samples. Streptococci were predominant in 40.8% and lactobacilli in 44.1% of the samples. Staphylococci were found in 27.6% of the samples, enterococci in 36.2%, and coliform in 13.8%. Yeast counts in excess of 1000/g were noted in 26.3% of the samples and mold counts >10/g in 17.8% of the samples. Psychrotrophs at levels >1000/g were found in 11.8% of the yogurts examined.

A total of 213 samples of various types of raw refrigerated ground beef from 51 different retail stores in Ontario were analyzed for their microbial content. Mesophilic and psychrotrophic counts on 64% of the samples were in excess of 10 million per gram. All samples yielded staphylococci with 98% containing >1000 organisms per gram. Coagulase-positive staphylococci were isolated from 17% of the samples. Enterococcus counts ranged from <10 to 10,000 per gram. About 95% of the samples had coliform counts in excess of 100 per gram and counts in individual samples varied from <10 to 100,000 per gram. Salmonellae were not isolated.

A total of 108 samples of fresh refrigerated ground beef, 99 samples of frozen hamburger patties, and 107 fried hamburgers, purchased from retail stores and fast-food outlets in Ontario, were analyzed for their bacteriological quality. About 44% of non-frozen ground beef samples had aerobic plate counts exceeding 50 million/g; 50 of 108 samples (46.3%) contained Staphylococcus aureus and 46 of these 50 samples (88%) exceeded 1000 organisms/g; 43 of 108 samples were positive for Escherichia coli with 38 samples (88.4%) exceeding 500 organisms/g. About 19% of frozen hamburger patties had aerobic plate counts in excess of 10 million/g; 93 of 99 samples (93.9%) contained S. aureus with 83 of these samples (89.3%) exceeding 1000 organisms/g; 28 of 99 samples were positive for E. coli with 7 of these samples (25%) exceeding 500 organisms/g. About 96.3% of fried hamburger samples had aerobic plate counts of less than 10,000/g.

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