Application of Complex Cryoprotectant on Takifugu Obscures during Frozen Storage

Abstract:

The cryoprotective effects of distilled water,4 g/dL trehalose,4 g/dL trehalose+0.4 g/dL sodium polyphosphate,and 4 g/dL trehalose+0.4 g/dL sodium polyphosphate+0.05 g/dL ε-polylysine in puffer fish(Takifugu obscures) were studied during storage at-18 ℃and-25 ℃ for up to 180 d using pH value,total volatile basic nitrogen(TVB-N),salt-extractable protein content and sulfhydryl(SH) content as indicators.The results showed the addition of trehalose and sodium polyphosphate could retard the protein denaturation of frozen puffer fish.This effect was better than that of cryoprotectant only included of trehalose,and the effect of distilled water was the worst.The antifreeze effect of ε-polylysine,trehalose and sodium polyphosphate compound produces at-25 ℃ was better than that at-18 ℃,which could restrain the protein denaturation and decomposition,and then improve the quality of frozen puffer fish.