Antifreeze Proteins and their Enhancement of Frozen Food Quality

Abstract

Artificial freezing has emerged as the most important method of preventing food spoilage, which is promoted largely by the high-water content in food items. However, the quality of organic frozen foods is undermined by ice recrystallization (IR), in which larger crystals grow while smaller crystals disappear. IR is exacerbated by temperature fluctuations, slow cooling rates, and high temperature storage, which are common conditions frozen food is exposed to in several steps between manufacture and consumption. The larger crystals formed are detrimental to food quality in that they produce a coarser texture in foods eaten frozen, such as ice cream. They are also damaging to defrosted organic foods since they can rupture cell walls, causing a drip that results in a loss of nutrients. In response to this issue, antifreeze proteins (AFPs) have been extensively studied, the incentive deriving from their documented crystal growth retardation activities. This paper provides a comprehensive understanding of the mechanisms of ice recrystallization, the role of antifreeze proteins in its inhibition as well as alternative methods available to inhibit it. This understanding is crucial to the optimalization of the maintenance of food quality and the extension of its shelf-life.