Effects of different freezing rates on the freezing characteristics of Ctenopharyngodon idellus C. et V fillets

In order to study influence degree, cause and mechanism of freezing rates on the freezing characteristics of Ctenopharyngodon idellus C. et V fillets, freezing curves and qualities (physicochemical and textural characteristics) of the fillets under four different freezing rates (3.69, 2.64, 0.60, 0.34 cm/h) were investigated. The results show that the freezing point of the fillets is (–0.6±0.1)℃. With the increasing of freezing rates, drip loss, salt-soluble protein content loss and Ca2+-ATPase activity loss rate decrease in some degrees, but moisture loss increases with the increasing of air velocity during freezing. Compared with the fresh fillets, the hardness and chewiness of the fast-frozen-thawed fillets don’t change, but those of the slow-frozen-thawed fillets decrease to some contents. The resilience of the frozen-thawed samples under the four freezing rates all decrease in different levels. Base on the synthetic evaluation on the testing results of the fillets’ physicochemical and textural characteristics, it can be concluded that increasing the freezing rates will help to maintain the original qualities of Ctenopharyngodon idellus C. et V fillets on the premise of decreasing moisture loss.