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.