Abstract: The changes of volatile odor substances in chilled Tan sheep meat stored for different periods (0, 2, 4, 6, 8 and 10 days) at 0–4 ℃ and cooked in boiling water were investigated using solid phase micro-extraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS) and an electronic nose system. In total, 38 volatile compounds were detected, including 19 aldehydes, 11 alcohols, 4 ketones, 3 acids and 1 heterocyclic compound. More specifically, the numbers of volatile compounds identified from meat samples stored for 0, 2, 4, 6, 8, and 10 days were 24, 26, 30, 32, 31 and 29, respectively, showing a trend of first increasing and then decreasing with storage period. The key aroma components in cooked meat were identified by relative odor activity value (ROAV). Among them, hexanal, octanal, heptanal, (E)-2-octenal, nonanal, benzaldehyde, 1-pentanol, 1-hexanol, 1-octene-3-ol, and 2-pentyl furan were common to all six samples with aldehydes being the predominant ones, contributing a lot to the flavor of cooked Tan sheep meat. The ROAV of aldehydes increased initially and then decreased, reaching the highest level on the 4th day. The results of the electronic nose showed that cooked four-day stored meat had greater odor intensity and better flavor.

Key words: Tan sheep meat; solid phase micro-extraction combined with gas chromatography-mass spectrometry; electronic nose; volatile odor substances