ABSTRACT
Growth of Bacillus cereus ATCC 33018 was evaluated in half and half (10.5% fat), whipping cream (30% fat), and nondairy creamer (7.5% fat). Samples were inoculated with approximately 10 vegetative cells/ml or 100 spores/ml and were subsequently stored at 4, 7, 23 and 32 degrees C. Within 9 h at 32 degrees C and 11 h at 23 degrees C, in both half and half and whipping cream, vegetative cells and spores reached population levels that can cause foodborne illness. No growth occurred in any product stored at 4 or 7 degrees C. Sodium stearoyl lactylate, a fatty acid derivative that is used as an emulsifier, inhibited growth of spores and vegetative cells in the nondairy creamers stored at either 32 or 23 degrees C.
Subject(s)
Bacillus cereus/growth & development , Coffee , Dairy Products/microbiology , Food, Formulated/microbiology , Temperature , Bacillaceae Infections/microbiology , Humans , Spores, Bacterial/physiologyABSTRACT
In order to determine the presence of the three environmental pathogens in dairy plants, six milk and four ice cream plants in a three state area were sampled. A total of 353 environmental samples were taken over three replications. Bacterial counts were performed on the environmental samples for chi-square analysis. Salmonella spp. were not isolated from any of the environmental samples. Yersinia enterocolitica was isolated from 6.8% of the environmental samples. Listeria monocytogenes was isolated from 6.5% of the environmental samples. Listeria spp. other than L. monocytogenes were isolated from 9.3% of the environmental samples. The presence of Y. enterocolitica was significantly related to high bacterial counts for six microbiological tests. The presence of L. monocytogenes was not related to high bacterial counts.
