Whey protein hydrolysates (WPH) were prepared from whey protein concentrate (WPC) by partial or extensive hydrolysis. WPC and two WPH types were characterized by a descriptive sensory analysis. WPC exhibited a "milky", "sweet", and "mild milk fat" odor, whereas extensively hydrolyzed whey protein (E-WPH) demonstrated "cheese-like", "acrid odor", and "sour" olfactory characteristics. In E-WPH, 3-(methylthio)-propanal, phenylacetaldehyde, and 3-methylbutanoic acid were specifically detected with high flavor dilution factors upon aroma extract dilution analysis. These odor-active compounds likely contributed to the olfactory characteristics of E-WPH, and their concentration increased together with that of their respective putative precursors: free methionine, phenylalanine, and leucine.
Keywords: aroma extract dilution analysis; degree of hydrolysis; odor-active compound; whey protein hydrolysates.
© 2018 Japanese Society of Animal Science.