[High-protein foods freeze freezer Change]

Many placed in the freezer of fish, meat and other animal foods, mainly composed of muscle protein is myofibrillar protein. In the freezing process, myofibrillar protein freeze denaturation occurs, the performance of salt-soluble reduced, ATP activity decreased, the viscosity of the salt solution is reduced, the protein molecules to produce three-dimensional spatial aggregation make changes in the structure and the like.

Denatured protein muscle tissue, reduce water retention, hard texture, taste worse, food processing as a raw material, processing suitability decline. As with protein freeze denaturation of fish meat as a raw material for surimi products - their products inelastic. Protein denaturation occurs frozen reason is not very clear, but that is mainly composed of one or several of the following reasons common cause:

① Junction food in the water when the formation of ice crystals were excluded salts, acids and gas impurities on the residual moisture moving tables frozen water day become concentrated solution. After the solution was concentrated protein foods and twist type contact. It will be due to salting and degeneration.

② Slow freezing produces large ice crystals muscle cells, muscle cells within the muscle fiber is pressed, assembled into bundles and because when ice crystals generated between binding protein molecules lose water, close to each other myofibrillar protein, protein reactive group with each other to form a variety of cross-linking, thereby causing aggregation.

③ Oxidation product of lipolysis can promote protein denaturation. Hydrolysis of fat cattle production of free fatty acids, but very unstable, oxidation resulting lower aldehydes, ketones and other products to promote protein denaturation. Oxidative hydrolysis of fat under the action of phospholipase is carried out, this enzyme is still very active at low temperatures. Usually due to the type of food, physiological conditions, different freezing conditions, but by one of the reasons leading role.