Abstract
Since the early 1960's when the aflatoxins were discovered, fungal contamination of foods has increasingly attracted the attention of food microbiologists in the world. As a causative agent of food spoilage, the fungal growth on the foods is rather distinguished from that of bacteria in the following physiological factors: 1) oxygen tension, 2) growth rate, 3) temperature, 4) moisture requirement, and 5) hydrogen-ion concentration (pH). Most raw foods are primarily exposed to fungal inoculum in the natural field. In the case of agricultural crops, sources of the primary populations of the fungi can be divided into plant and its environment such as soil. Especially important are species of Alternaria, Chaetomium, Cladosporium, Curvularia, Drechslera, Epicoccum, Fusarium, Nigrospora, Pithomyces, Trichoderma, and Ulocladium, as well as some of Aspergillus and Penicillium. The primary invaders frequently survive during handling and processing of the foods, although secondary contamination may come from equipment, from packaging materials and from personnel. Because of the survival of fungi introduced from the environmental sources, more adequate assessment for the primary contamination of the foods will possibly be needed.
