Abstract: In this study, the flavor characteristics and volatile compounds of cold-pressed flaxseed oil were analyzed using quantitative descriptive analysis, headspace solid phase microextraction and simultaneous distillation extraction coupled with gas chromatography-mass spectrometry-olfactometry (GC-MS-O) and chemometrics. The results showed that cold-pressed flaxseed oil had a unique flavor, mainly presenting fresh grassy and fishy flavors. Totally 34 characteristic volatile components were detected, including 12 aldehydes, 7 alcohols, 5 acids, 3 terpenes, 3 alkanes, 2 ketones and 2 aromatic compounds. Based on GC-O analysis, detection frequency (DF ≥ 6) and odor activity value (OAV ≥ 1), 2-ethyl hexanol, hexanol, (E)-2-hexenal, hexanal, and (E,E)-2,4-heptadienal were found to be the major contributors to the grassy flavor, and (Z)-4-heptenal the major contributor to fishy flavor. Principal component analysis (PCA) validated the correlation between the characteristic flavor intensity and the sensory flavor attributes of cold-pressed flaxseed oil from different regions. The results of this study can provide a theoretical basis for improving the aroma, processing and quality of cold-pressed flaxseed oil.

Key words: cold-pressed flaxseed oils; gas chromatography-mass spectrometry-olfactometry; odor activity value; detection frequency