Optimization of protein hydrolysates production from defatted peanut meal based on physicochemical characteristics and sensory analysis

Three enzymes, GA (Genencor Alkaline Protease), GN (Genencor Neutral Protease) and Protamex were used to prepare protein hydrolysates from defatted peanut meal (DPM). The physicochemical properties of defatted peanut meal hydrolysate (DPMH) and the changes of flavor were determined. DPMHs had lower isoelectric points, zeta potential values and better solubility. The DPMH of GN showed the best emulsifying activity and the emulsion stability. Volatile organic compounds (VOCs) changed significantly with the most drastic changes at 4–6 h. About 50 VOCs were labeled using GC-IMS. The fingerprint of smell change was established, and the enzymolysis reaction could be divided into different stages according to the change of flavor. DPMHs of GA and Protamex showed stronger astringency and bitterness, while stronger umami was shown in DPMH of GN. This research provides basic data support for enzyme selection, sensory and reaction stage control to obtain enzymatic polypeptides with improved properties from DPM.