Microorganisms are the tiniest, most prolific life forms on earth. These include bacteria, yeasts, molds, and viruses, termed “microorganisms” because of their size (micro meaning small and organism meaning living being). Most are harmless, many are highly beneficial, some indicate the probable presence of filth, disease organisms, spoilage and a few cause disease.
There are several factors that affect the growth of microorganisms, including temperature, water activity, pH, population, and oxygen. Although some factors affecting growth are considered separately in the following fact sheets, these factors occur simultaneously in nature. It is important for the food entrepreneur to have a basic fundamental knowledge of microbiology in order to safely produce products in a food production environment.