The inhibition mechanism of the texture deterioration of tilapia fillets during partial freezing after treatment with polyphenols.

The inhibition mechanism of the texture deterioration of tilapia fillets after treatment with polyphenols during partial freezing for 49 days was studied. Carnosic acid (CA), procyanidin (PA), quercetin (QE), and resveratrol (RSV) treatments had significantly higher hardness values (over 230 g) than the control group (183 g) on day 49 (P < 0.05). Polyphenol treatments were effective in delaying the protein degradation, lipid oxidation and spoilage microbe growth. Moreover, the kinetic model showed that the predicted shelf life of tilapia fillets treated with PA (102 d) was extended by 25 d compared to the control group (77 d). It was the proposed possible mechanism that polyphenols comprehensively maintained the protein conformation (increased hydrogen bonds and decreased disulfide bonds) and retarded protein denaturation and degradation, protecting the texture of the fillets. Therefore, polyphenols can be used to maintain texture and extend the shelf life of tilapia fillets during partial freezing.