Gelatin hydrolysate in freeze–thawed shrimp model system: retardation of weight loss and muscle protein denaturation

Abstract

This research explores the cryoprotective potential of gelatin hydrolysate by determining weight loss and physicochemical changes in the muscle protein of freeze–thawed shrimp. Shrimp treated with gelatin hydrolysate exhibited significantly higher and lower weight gain (9.20%) than those treated with distilled water (0.93%) and mixed phosphates (16.99%), respectively. Gelatin hydrolysate could lower the increasing rate of thawing and cooking loss and freezable water content in freeze–thawed shrimp (P < 0.05) and comparable to those of mixed phosphates treated shrimp (P > 0.05). As the shrimp were subjected to freeze–thawing, gelatin hydrolysate slowed the decline of protein solubility and Ca²⁺-ATPase activity and mitigated the rise of surface hydrophobicity and disulfide bond content. It also delayed the shear force increase. These findings suggest that gelatin hydrolysate could be an effective alternative to traditional cryoprotectants, retarding weight loss and protein denaturation to preserve shrimp quality during freezing and frozen storage.