Temperatures in Home Refrigerators and Mold Growth at Refrigeration Temperatures

Air temperature in two home refrigerators ranged from 1.7 to 20.2 C during 4-day periods. Mean air temperatures at thermocouple locations varied from 3.9 to 11.9 C, and temperature changes resulting from opening refrigerators were usually 3 C or less, although increases as great as 18.5 C were recorded. Temperatures in the range at which refrigerators operated were evaluated for their effect on mold growth. Mycelia from a strain of aflatoxin-producing Aspergillus did not grow at 8 C during 504 h of incubation. Isolates of Pencillium obtained from refrigerated food had optimum growth rates of mycelia at 15 C or above but grew at 5 C. However, incubation at 5 C prevented germination of spores of all but one of the isolates that were tested.