Survival of Heated Streptococcus faecalis as Affected by Phase of Growth and Incubation Temperature after Thermal Exposure

SUMMARY Effects of the growth phase of 3 Streptococcus faecalis strains on heat resistance at 60° was studied. During the initial and middle logarithmic growth phases no resistance to 60° was found. Organisms heated in a stationary phase of growth were incubated at temperatures ranging from 45 to 7.3° to determine the effect of incubation temperature on their survival. Maximum survival of heated organisms was observed at optimum growth temperatures of c. 30°. The incubation time required for maximum recovery was longer for heated than for unheated organisms, regardless of the incubation temperature.