Associations between Maillard α-dicarbonyl intermediates and aroma compounds in fragrant Camellia oleifera seed oil.

Fragrant Camellia oleifera seed oil (FCSO) acquires its characteristic aroma primarily through roasting. This study elucidates the potential role of α-dicarbonyl compounds (α-DCs), including glyoxal (GO), methylglyoxal (MGO), and 3-deoxyglucosone (3-DG), as Maillard reaction intermediates in flavor formation, particularly in oil-phase systems. Through a simplified glucose-phenylalanine model, the effects of temperature, time, substrate molar ratio, and pH on α-DC generation were systematically evaluated. The results showed 140 °C for 120 min as optimal for α-DC generation. HS-SPME/GC-MS and multivariate analysis revealed aldehydes, ketones, and alcohols as dominant volatiles. In the model system, GO was significantly correlated with benzaldehyde, whereas 3-DG was significantly correlated with phenethyl alcohol. The authentic FCSO showed an increase of 12.21 μg/kg for benzaldehyde and 3.71 μg/kg for phenethyl alcohol. These findings potentially demonstrated the α-DC-mediated flavor formation mechanism and might provide a theoretical foundation for targeted aroma enhancement in FCSO processing.