Influence of reducing sugars and protein-to-sugar ratios on volatile profile, pH, and browning intensity of Maillard-reacted nutritional yeast hydrolysate

Abstract This study investigated the effects of reducing sugars and protein-to-sugar ratios on generating volatile compounds from nutritional yeast hydrolysates after Maillard reaction. Nutritional yeast extract (NYE) was cleaved using Flavourzyme® at an enzyme-to-substrate ratio of 0.5% w/w, followed by heat treatment with varying concentrations of reducing sugars (i.e., hexoses: glucose and fructose and pentoses: xylose and ribose). The results showed that pentoses generate higher numbers and concentrations of volatiles than hexoses, especially furans, Strecker aldehydes, and sulphur-containing compounds such as dimethyl disulphide. However, hexoses produced higher concentrations of pyrazines. Strecker aldehydes and pyrazines served as key aroma-active compounds in meat aroma. Likewise, sulphur-containing compounds played an important role in meat aroma due to their low detection threshold. The results showed that reducing sugars significantly impacts the volatile profile of NYE, potentially influencing the formation of meaty aroma compounds. These findings demonstrate the potential of MRPs to enhance meaty flavours due to the presence of volatile compounds with characteristics of cooked meat.