Abstract: The volatile compounds of sunflower butters produced with different initial moisture contents at different roasting temperatures were identified by headspace solid-phase micro-extraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS). Principal component analysis (PCA) was?performed?to determine the key flavor components of sunflower butters based on relative odor activity values (ROAV). The?results?showed?that the relative contents of heterocycles such as 2,5-dimethylpyrazine in sunflower butter prepared from roasted sunflower seeds were significantly increased in comparison with that prepared from unroasted sunflower seeds whereas the relative contents of aldehydes were significantly decreased. Sunflower butter made from sunflower seeds roasted at 170 ℃ had a richer flavor. The highest relative content of pyrazines was found in sunflower butter with initial water content of 5.40%. Increased initial moisture content reduced the relative content of pyrazines but increased the relative content of aldehydes causing a negative impact on the flavor of sunflower butters. PCA indicated that n-hexanol and acetic acid were the characteristic flavor substances of sunflower butter prepared from unroasted seeds. Aldehydes such as n-hexanal, octanal and (E,E)-2,4-decadienal were the characteristic flavor substances of sunflower butter made from sunflower seeds roasted at 140 ℃, having an oxidized lipid-like flavor. Pyrazines such as 2,3,5-trimethylpyrazine, 3-ethyl-2,5-dimethylpyrazine, and 2,3-diethyl-5-methylpyrazine were the characteristic flavor substances of sunflower butters made from sunflower seeds roasted at 170 and 200 ℃, having a noticeable roasted flavor.

Key words: sunflower butter; volatile compounds; gas chromatography-mass spectrometry; relative odor activity value; principal component analysis