Effect of ultrasound combined with TGase-type glycation on the structure, physicochemical, and functional properties of casein hydrolysate

This study investigated the effects of transglutaminase (TGase)-type glycation combined with ultrasound treatment on the structure, physicochemical properties, and functional properties of casein hydrolysate (CH). The results showed that TGase-type glycation and ultrasound treatment changed the secondary structure and reduced the fluorescence intensity of CH. Structural analysis revealed the intermolecular covalent interactions between oligochitosan and CH, confirming the occurrence of TGase-type glycation. The microstructure indicated that after 200 W sonication treatment, the structure of glycated CH was expanded and the molecular flexibility was enhanced. In addition, glycated CH treated with ultrasound treatment exhibited superior solubility, foaming capacity, antioxidant activity, and thermal stability. This study provides new insights into the combination of TGase-type glycation and ultrasound treatment, which may improve the function of casein and further increase its application in the food industry.