Decode the specific flavor and spectral fingerprint of the proteolytic products of milk-derived defatted high protein.

Proteolysis is crucial for generating functional ingredients that enhance milk quality, yet the associated odor and taste profiles of the proteolytic hydrolysates remain poorly characterized. This study utilized a multidimensional approach to analyze the volatile compounds, the peptidome, and spectroscopic properties of defatted high-protein enzymatic hydrolysates under varying conditions. Sensory evaluation integrated with facial expression was applied to comprehensively assess flavor profiles across different enzymatic hydrolysis treatments. Results showed significant differences between enzymatically treated samples and the control (CK): levels of 2-heptanone, valeraldehyde, and hexanal decreased, while benzaldehyde, 3-methylbutanal, and furanaldehyde (except in neutral hydrolysis) increased. Compared to other enzymatically hydrolyzed samples, the combination of flavourzyme and glutaminase exhibited the highest scores for richness and umami. Additionally, a total of 333 umami-active peptides were predicted. This research demonstrates that enzymatic modification can advance flavor technology, improve product sensory experience, and establish a theoretical framework for developing premium dairy products.