Identification of Bacteria Isolated from Fresh and Temperature Abused Variety Meats

Abstract

The microflora associated with fresh and temperature abused beef livers, kidneys, hearts, tongues and pork livers was identified. Variety meats were obtained from a packing plant and allocated to three packaging treatments, i.e., vacuum packaging, polyvinyl chloride film wrapping and no wrapping (unwrapped). Isolates were characterized from fresh variety meats following frozen storage for three weeks at −29 ± 2 C; and following simulated temperature abuse. Classification of 1555 isolates obtained from aerobic plate counts at 35, 20 and 7 C is provided. Fresh variety meats were found to be contaminated with a variety of bacteria commonly associated with fresh red meats immediately post-mortem, with Micrococcus sp. being the most frequently isolated gram-positive bacterium and Escherichia coli the predominating gram-negative isolate. Frozen variety meats before simulated temperature abuse reflected a higher proportion of gram-positive organisms and fewer Enterobacteriaceae than fresh variety meats. Abused variety meats yielded predominately Pseudomonas strains, except where vacuum packaging was used, in which case isolates were predominately Lactobacillus sp. and Micrococcus.