1.1.7: Activity of Water - Foods

An important scientific literature comments on the activity of water in the context of biochemistry and of the very important industry concerned with foods.[1-4]

Scott [5] identified the importance of water activity and microbial growth on foodstuffs; e.g. chilled beef. Hartel reviews the problem of freezing of water in, for example, ice cream; [6] see also comments on water activity in sucrose+ water systems.[1] The importance of water activity in sensory crispness and mechanical deformation of snack products is discussed by Katz and Labula. [7] Water activity is an important variable in fungal spoilage of food.[8,9]

Berg and Bruin review[10] the role of activity, not necessarily the water content, in the context of the deterioration of food, a matter of concern for humans from earliest times. In fact water activity, a1 is a major control variable in food preservation although the chemistry of food deterioration is complicated.

Crucially important in this context are publications produced by the National Institute of Standards and Technology .[11]

Footnotes

[1] P. Walstra, Physical Chemistry of Foods, M. Dekker, New York,2003.

[2] Water Activity: Influences on Food Quality, ed. L. B. Rockland and G. F. Stewart, Academic Press, New York,1981.

[3] A. J. Fontana Jr., Cereal Foods World,2000,45,7.

[4] A. J. Fontana and C. S. Campbell, Handbook of Food Analysis, volume 1, Physical Characterization and Nutrient Analysis , 2nd edn (revised and expanded) e.d. L. M.L. Nollet, 2004, M. Dekker, <New York

[5] W. J. Scott, Adv. Food Res.,1957,7,83.

[6] R.W. Hartel, Crystallizaiton in Foods, Aspen, Maryland, 2001.

[7] E. Katz and T. P. Labuza, J. Food Science,1981,46,403.

[8] R. Beauchat, J. Food Protection, 1983.46,135.

[9] W. H. Sperber, J. Food Protection, 1983.46,142.

[10] C. van den Berg and S. Bruin, Water Activity : Influence on Food Quality , ed. L. B. Rockford and G. F. Stewart, Academic Press, New York1981, pages 1-62.

[11] U. S. Food and Drug Administration, Title 21, Code of Federal Regulations, Parts 108, 110, 113 and 114, U. S. Government Printing Office, Washington, DC,1998.

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