Abstract:In this study, the flavor profiles of rice bran oil products prepared by heating fresh and extruded bran extracts with rice bran oil were evaluated and the formation mechanism of key flavor compounds was investigated. The results showed that rice bran oil prepared from fresh bran had more pronounced caramel sweetness and higher sensory quality score. Headspace solid-phase microextraction-gas chromatography and the flavor analysis based on relative odor activity values （ROAV） revealed that typical Maillard reaction products such as 4-hydroxy-2,5-dimethyl-3-(2H)furanone, 2,3-dihydro-3,5-dihydroxy-6-methyl-4(H)-pyran-4-one,3-methyl-butyraldehyde, phenylacetaldehyde, and maltol were the key flavor compounds in the oil samples prepared from fresh bran. There was no significant difference in the consumption of amino acids in the extract before and after reaction. However, the consumption of reducing sugar in fresh bran extract (5 514.26 mg/kg) was higher (4 715.69 mg/kg) than that in extruded bran extract. When reducing sugars were added to the extract of extruded bran, the product showed increased content of key aromatic compounds, with the sensory profile aligned with that of the product prepared from fresh bran. These findings suggest that flavor compounds of flavored rice bran oil were primarily produced by Maillard reaction and the flavor differences between the oil products prepared from extruded and fresh rice bran oil were due to the lower reducing sugar content in extruded bran. This study provides a theoretical basis for developing flavored rice bran oil.
