Effects of Different Cryoprotectant on the Quality Characteristics of Squid Mince during Frozen Storage

In order to improve the quality stability of frozen reconstructed squid mince, the influence of three additions at various concentrations, namely trehalose (2%, 4%, 6%), lactitol (2%, 4%, 6%), and sodium lactate (2%, 3%, 4%) on the cryoprotective effect of squid mince during 5-month frozen storage was evaluated using Peru squid as raw materials. Gel strength, water holding capacity, Ca²⁺-ATPase activity, water distribution, and microstructures were monitored. The results showed that trehalose, lactitol, and sodium lactate could effectively improve the gel strength and water-holding capacity with increasing addition amounts (P<0.05). After 5-month frozen storage, the Ca²⁺-ATPase activity of quid mince added with 6% trehalose, 6% lactitol and 4% sodium lactate was 0.28, 0.26 and 0.30 μmol Pi/(mg prot·h) respectively, significantly higher than the control group 0.17 μmol Pi/(mg prot·h) (P<0.05), indicating the denaturation of myofibrillar protein of squid mince was delayed. SEM results showed that the microstructures of squid mince added with 6% trehalose and 4% sodium lactate were more compact with a well-kept gel network matrix compared with the control group and mince added with lactitol during frozen storage. Combined with sensory evaluation, 6% trehalose could enhance the mouthfeel and overall acceptance of squid mince. Overall, 6% trehalose could effectively delay the quality change of squid sliders during frozen storage, and would provide a theoretical foundation for the utilization of Peru squid and its frozen prepared products.