Preservation effect of complex biological preservative combined with ice temperature storage on Takifugu rubripes

The aim of this paper was to optimize complex biological preservatives consisting of citric acid, thymol and sodium alginate using three-variable, three-level Box-Behnken design to prolong the shelf life of Takifugu rubripes. A quadratic polynomial regression model was established with total plate counts as the response value. The preservation effects of complex biological preservatives were verified by measuring pH, drip loss, TVB-N, TBA, total plate counts and Pseudomonas sp.. The result showed that the optimal ratio of the complex biological preservatives at ice temperature is as follows: 0.68% citric acid, 1.45% thymol and 1.94% sodium alginate. In that condition, the lowest total plate count was 5.50 lg (CFU/g) on the 30th day. What’s more, citric acid and thymol, citric acid and sodium alginate, as well as thymol and sodium alginate had a significant interactive effect. The optimal complex biological preservatives could significantly inhibit the growth of microorganisms, and reduce the contents of TVB-N and TBA. It was proved that the complex biological preservatives could effectively delay the deterioration of T. rubripes, prolonging the shelf life of 15 d to 30 d.