Effect of Egg White Protein-β-Cyclodextrin Complex on Freeze-Thaw Stability of Shrimp

A new antifreeze agent was prepared from Egg White Protein (EWP) and β-Cyclodextrin (β-CD). Through single factor experiments and response surface test, the preparation conditions of EWP-β-CD complex with the best antifreeze activity were obtained. Then EWP-β-CD complex with different concentrations (2%, 4% and 6%) was applied to the four freeze-thaw cycle system of shrimp to study the antifreeze protection of EWP-β-CD complex on shrimp. The results showed that the optimum conditions for the preparation of EWP-β-CD composite system were pH7.0, the composite ratio of β-CD and EWP 1:10, the heat treatment temperature 75 ℃. The antifreeze activity of EWP-β-CD composite system was 84.09%±1.06% under the optimal conditions. The EWP-β-CD complex under this condition was applied to the freeze-thaw cycle of shrimp. After adding EWP-β-CD complex, the water retention, hardness and chewability of shrimps were significantly improved, and the chromaticity of shrimps was not significantly affected. When the addition of EWP-β-CD complex was 4% and 6%, the effect of EWP-β-CD complex on protein degradation and fat oxidation of shrimp was significantly better than that of commercial antifreeze. The preparation conditions of EWP-β-CD complex are optimized by response surface method, and it was preliminarily showed that it had a certain protective effect on the quality of shrimp. This result would provide a theoretical basis for the subsequent development of low sweetness and low calorie antifreeze.