Effects of Transglutaminase and Heat Treatment on the Structure and Gelation Properties of Camel Casein Protein

This study investigated the effects of transglutaminase (TGase) content (0%, 0.5%, 1%, 1.5%) and heat treatment (25 °C, 70 °C, 80 °C, 90 °C) on the structure and gel properties of camel casein protein. The results indicate that a TGase concentration of 0.5% combined with a heat treatment of 90 °C in SDS-PAGE facilitates the aggregation and crosslinking of protein molecules to form polymers, with the degree of crosslinking increasing alongside the TGase concentration. In FTIR, the treatment with TGase and heat resulted in a shift of the absorption peak of the amide I band, indicating a transition of the secondary structure from a loose to an ordered configuration. Additionally, surface hydrophobicity and heat enthalpy values were significantly increased, while the thermal transition temperature of casein gradually decreased. Following TGase binding and heat treatment, casein protein molecules formed a network structure characterized by small pore sizes and close crosslinking. Rheological analysis revealed that 0.5% TGase treatment significantly lowered the gel formation point of casein, promoted gelation, and effectively enhanced the mechanical properties and water-holding capacity of the casein gels. These findings provide theoretical reference for the development of camel protein modification and gel products.