ABSTRACT
Freezing provides a significant extended shelf life, and it is successfully employed for the long-term preservation of many foods. The detrimental effects of freezing on microorganisms may be desirable or undesirable, depending on the types of food products. Dehydration or weight loss should be regarded as an important quality parameter for frozen unpacked foods, mainly in animal tissue. The glass transition has a dramatic effect on frozen food quality. The functional properties of any food product are normally affected by differences in freezing and thawing methods. The development of rancid flavors and progressive toughening accompanied by the development of cold store flavor are the principal sensory changes in seafood. Oxygen is the bugbear of almost all frozen foods, leading to oxidative rancidity, loss of color, and development of off-flavors. The retention of nutritional components in foods is a concern when any type of preservation method is used, but freezing is probably the least destructive.
