Abstract: Solvent-assisted flavor evaporation (SAFE) or simultaneous distillation extraction (SDE) combined with gas chromatography-mass spectrometry (GC-MS) was used to evaluate and determine the types and contents of volatile components in fragrant peanut oils prepared from high-oleic acid and ordinary peanuts under the same conditions. The quality differences between the two kinds of peanuts and between the two kinds of peanut oils were analyzed in terms of sensory evaluation, fatty acid composition, amino acid composition, basic physicochemical properties, and nutritional composition. In addition, the difference between the volatile contents determined using SAFE and SDE was analyzed. Results indicated that the two kinds of peanuts significantly differed with respect to fatty and amino acid composition. The extraction efficiency of SAFE for volatiles was obviously higher than of SDE. Using SAFE combined with GC-MS, 112 and 127 volatile components were detected from high-oleic acid and ordinary peanut oil, at a total amount of 33 945.28 and 46 700.22 μg/kg, respectively, and the two kinds of peanut oils had significant differences in the contents of volatile components such as aldehydes, phenols, furans and pyrazines. The contents of all volatile components except pyrroles were significantly higher in high-oleic acid peanut oil than in ordinary peanut oil. Partial least squares discriminant analysis (PLS-DA) combined with odor activity value (OAV) was used to identify 18 characteristic volatile flavor components that contributed to the sensory difference between the two kinds of peanut oils, which were detected in both oil samples and at higher levels in regular peanut oil. Further analysis revealed that furanone had the most significant influence on the flavor of the two kinds of peanut oils, and made an important contribution to the sweetness of peanut oil. Furthermore, eight pyrazines such as 2,5-dimethylpyrazine, 3,5-diethyl-2-methyl-pyrazine, 2,5-diethyl-pyrazine, 2-ethyl-6-methyl-pyrazine, 2,3-diethyl-5-methyl-pyrazine, 2-methyl-pyrazine, 2,3-dimethyl-5-ethyl-pyrazine, and 2-vinyl-5-methyl-pyrazine had important effects on the difference in the characteristic nutty or roasted flavor of peanut oil. Four aldehydes, including trans-2-octenal, n-hexenal, n-octenal and heptanal, contributed to the difference in the fatty flavor of two kinds of peanut oil. Dimethyl trisulfide, 2,3-pentanedione, N-methyl-2-pyrrole formaldehyde, 2-pentylfuran, and n-tridecane were important contributors to the difference in the sweetness and pungency of both kinds of peanut oils. The results of sensory evaluation showed that each sensory attribute of regular peanut oil was significantly stronger than that of high-oleic peanut oil, which is consistent with the results of volatile components. These results can provide support for precise flavor control in the production of fragrant peanut oil.

Key words: peanuts; fragrant peanut oil; solvent-assisted evaporation; simultaneous distillation extraction; gas chromatography-mass spectrometry; volatile flavor components; sensory evaluation