DRIED WHOLE EGG POWDER: VII. EFFECT OF TEMPERATURE AND MOISTURE ON THE BACTERIAL CONTENT OF LIQUID AND DRIED EGG

Abstract

The bacterial content of liquid egg increased rapidly after about six hours at 20 °C., 12 hr. at 15.6 °C., 25 hr. at 11.1 °C., and two to three days at 7.2 °C. At 3.3 °C. there was little change for five to six days, followed by a very gradual increase.The bacterial content of dried egg powder was influenced by the number of bacteria in the melange, the drying temperature, the rate of cooling, the storage temperature, and the moisture content. Low drying temperature and rapid cooling of the powder favoured survival. On storage the bacterial mortality increased with increasing time and temperature. At temperatures above 30 °C. the death rate seemed to be proportional to changes in temperature. At 7.2 °C. and lower the majority of organisms survived eight months' storage. Up to 8.6%, moisture content had little effect on bacterial survival. At moisture levels above 5% there was an increase in the number of moulds, particularly at 23.9° and 32.2 °C.