Abstract
An experiment was conducted to elucidate the food-hygienic significance of bacteria of raw meat; 1, 056 bacterial strains isolated from refrigerated and frozen raw meat were examined for ability to decompose fat and protein. Some representative strains were also observed for growth characteristics at low temperature.
1) The ratio of lipolytic and proteolytic bacteria to those isolated varied to some extent with the temperature at which isolation was done, the kind of meat (i. e.; beef, pork, or chicken meat), and the mode of storage (i. e., refrigerated or frozen meat).
2) When the isolated bacteria were analyzed by genus, more than 70% of bacteria belonging to Alcaligenes, Acinetobacter, and Pseudomonas showed lipolytic activity, and nearly 80% of bacteria belonging to Pseudomonas showed proteolytic activity.
3) The isolated bacteria were analyzed for range of growth temperature to be divided into 7 groups. Each group was examined for the rates of lipolytic and proteolytic bacteria. The highest rate of lipolytic bacteria was obtained from the group growing in a range of 7-32°C. The highest rate of proteolytic bacteria was obtained from the group growing in a range of 7-25°C.
4) The rates of growth at 1 and 5°C were the highest in some of the coryneforms and Pseudomonas and rather low in Lactobacillus and Micrococcus. The growth rate was not parallel with the upper limit of the growth temperature in the bacterial strains examined.
