Physiological and Metabolic Attributes of Microbial Groups Associated with Foods

Foods often become unfit for consumption due to microbial contamination. Microbes may cause 2 different types of undesirable phenomena. The most obvious is that the foods spoil; that is, the amounts of microbial metabolites formed can be detected organoleptically. Another is that organisms capable of causing enteric disease develop in foods; a rather vexing aspect of this is that most of the foods dangerously contaminated in this way are not overtly spoiled. Though foodborne diseases can sometimes be caused by small numbers of microbes, spoilage of foods by microbial mechanisms always requires elevated numbers of cells to be present: the metabolic activity of small numbers of cells is SO low that organoleptically detectable concentrations of metabolites do not become evident. It b, therefore, essential to distinguish between the phenomena of contamination of foods versus microbial proliferation in foods (Mossel, 1969).