Changes in protein function of Persian sturgeon (Acipenser persicus) fillet during processing

In order to study some protein quality indicators of Persian sturgeon fillet during processing, changes in protein, protein solubility and sulfhydryl group (SH) were investigated after cookingthawing and reheating treatments. Protein content in raw fillet of Persian sturgeon was 20.69% that shows the importance of animal proteins consumption in dietary. Grilling caused significant increase in protein percentage of fillets (p<0.05). Thawing in microwave and also grilling of fillets after thawing resulted in more decrease in protein content than refrigerator thawing. The most changes in protein solubility were observed after cooking as it decreased after grilling (P 0.05) but none of thawing methods and subsequent cooking had significant effect on protein solubility, except in several pHs. All processing methods decreased the –SH group. Results of this study showed that thawing and subsequent grilling result in decrease in Persian sturgeon protein quality but in many cases these changes are not significant and among these, most changes occur due to cooking process.