Microbes is everywhere in environment and food may be attacked with it through different ways. As microorganisms attack foods they produce chemicals that will make the food unpleasant to taste or they will cause illness. In some instances, the microorganisms themselves infect consumers causing illness and occasionally death. There comes a point at which the food becomes unacceptable and possibly dangerous. The rate at which growth occurs depends on the factors listed here and may be considered when determining whether a food requires time/temperature control during storage, distribution, and handling at retail and in food service to assure consumer protection. Generally, the rate at which microorganisms grow on foods depends on:

·         Time and temperature,

·         pH and acidity,

·         Available moisture (water content)

·         Nutrients available in food

·         Type of packaging

·         Processing steps

·         Biological structure

·         Intended use of products

·         Storage conditions

·         Presence of preservatives such as sugar, salt and chemical preservatives

References:

1.      Herbert, R.A.: Microbial growth at low temperatures. In: Gould, G.W. (Ed.) Mechanism of action of food preservation procedures, p. 71. Elsevier Applied Science: London (1989)

2.      Karel, M., Water activity and food preservation. In: Principles of food science, Part II (Editors: Karel, M., Fennema, O. R., Lund, D. B.), p. 237. New York: Marcel Dekker, Inc., 1975

3.      H.-D. Belitz · W. Grosch · P. Schieberle, Food Chemistry, 4th revised and extended ed., Berlin (2009), ISBN 978-3-540-69933-0

4.      Richard Beyer, Manual on Food Packaging for Small and Medium Size Enterprises in Samoa, Apia, 2012

5.      A Report of the Institute of Food Technologists for the Food and Drug Administration of the United States Department of Health and Human Services Comprehensive Reviews in Food Science and Food Safety, Vol. 2, 2003