Modulation of Maillard reaction pathways and aroma profiles in peanut oil using enzymatically tailored peanut meal hydrolysates

This study establishes a mechanistic framework for directing Maillard-driven aroma formation in peanut oil through targeted enzymatic precursor engineering, exploring the potential of precursor engineering for flavor modulation in peanut oil. Defatted peanut meal was subjected to selective hydrolysis using distinct glycosidases (cellulase, hemicellulase, pectinase, α-amylase, and amyloglucosidase) in combination with proteases to systematically reconstruct the precursor microenvironment (reducing sugars and free amino acids). The resulting hydrolysates were thermally reacted with cold-pressed peanut oil at 120 °C, and the evolution of volatile profiles and sensory attributes was evaluated using an integrated sensory-directed flavoromics approach. Two enzymatic strategies, pectinase-protease and α-amylase-protease, emerged as highly effective in reprogramming Maillard pathways. These treatments generated a substantial expansion of key precursors, particularly glucose (up to >60-fold increase) and branched-chain amino acids, which were associated with selective formation of pyrazines and furan derivatives associated with roasted, savory, and caramel notes. Concurrently, lipid-derived off-flavor compounds such as hexanal and 1-octen-3-ol were significantly suppressed, indicating a possible shift in reaction dominance from lipid oxidation to Maillard chemistry. Correlation and network analyses revealed the precursor-volatile-sensory linkages, suggesting that specific precursor compositions (e.g., glucose-leucine-lysine systems) are associated with distinct aroma profiles. Notably, pentose-rich systems were associated with furan pathway activation, whereas hexose-dominant systems were associated with pyrazine formation. These findings provide evidence that enzyme-tailored precursor engineering can influence Maillard reaction pathways in edible oils in a potentially tunable manner, offering a promising strategy for producing peanut oil with tailored flavor profiles and suggesting potential improvements in oxidative stability.