Structural Modification of Milk Proteins During Yogurt Processing: Effects on Protein Digestion and Absorption

Yogurt is a popular functional dairy product prized for health benefits and nutritional value, especially as a significant source of high-quality proteins. In recent years, the research on the processing-induced modification of milk protein structure to regulate its nutritional properties has attracted much attention. Although yogurt processing has been extensively studied at the physicochemical level, novel processing technologies continue to emerge. At the same time, increasing attention has been directed toward digestion-driven nutritional functionality, calling for a renewed, digestion-oriented interpretation of processing-induced protein modifications and their downstream physiological relevance. The review synthesizes current knowledge on how key yogurt processing technologies-standardization, homogenization, heat treatment, and fermentation-govern milk protein structural transformations, gel network formation, and bioactive peptide generation. Particular emphasis is placed on linking processing-induced protein changes with gastrointestinal digestion behaviors, including gastric emptying, enzymatic hydrolysis, and nutrient absorption. Precisely, processing-driven protein denaturation, aggregation, redistribution, and hydrolysis collectively determine yogurt matrix architecture and its digestive fate. Structural features of the yogurt matrix modulate gastric emptying kinetics, whereas protein conformational changes influence enzymatic accessibility and hydrolysis rates. Fermentation-associated proteolysis further alters the profile and availability of absorbable peptides and amino acids. This review may help for advancing yogurt production from standardized processing toward precision nutrition design and for developing functional yogurts with targeted digestive and health benefits.