I. Behavior in Refrigerated Foods

Abstract

Mixed cultures of Salmonella senftenberg 775W, S. enteritidis, S. manhattan, and mixed cultures of Staphylococcus aureus 196E, MF159, and Msl49 were cultured in custard, chicken a la king, and ham salad for 5 days at 2[degree]F intervals from 40[degree]F to 50[degree]F and 95[degree]F and for 24 hours at 2[degree]F intervals from 112[degree]F to 120[degree]F and 95[degree]F. In custard, the staphylococci grew at temperatures of 44[degree]F to 50[degree]F. The salmonellae underwent a gradual decrease in numbers at all temperatures from 40[degree]F to 50[degree]F. Both groups of organisms grew at 114[degree]F, but decreased in numbers at 116[degree]F through 120[degree]F. In chicken a la king, growth of both salmonellae and staphylococci occurred at temperatures of 44[degree]F through 50[degree]F. At 112[degree]F, the staphylococci grew, but were killed at all higher temperatures. The salmonellae grew at 114[degree]F, but were killed at 116[degree]F and above. In ham salad, no growth of either group of organisms occurred at 40[degree]F through 50[degree]F, and a decrease in numbers of both groups was noted at 112[degree]F through 120[degree]F. Good growth of both groups of organisms was observed in all 3 foods incubated at 95[degree]F. The results indicate that the temperature growth range for salmonellae and staphylococci in foods of the type studied is 44[degree]F to 114[degree]F; and that holding perishable foods in the mid-portion of this range for periods that permit growth of salmonellae and staphylococci may result in dangerous increases of these organisms when present and is a practice to be avoided during food preparation services.