Effects of thyme (Thymus vulgaris L.) polyphenol addition on the flavor profiles of stewed lamb meat using SPME-GC-MS and E-nose

To investigate the effects of thyme addition on lamb flavor and reveal the mechanisms of its aroma formation, 6 samples (normal lamb meat, lean meat, lamb tallow, and their corresponding thyme phenolic extract (TP) added samples) were analyzed and compared. Sensory evaluation and electronic nose analysis showed that TP could markedly modify the aroma profile of lamb ( p < 0.05), particularly in the weakening of muttony attribute. A total of 71 compounds were identified, among which 26 were perceived by GC-MS/O and odor activity values (OAV). All 3 pairs of samples showed that the addition of TP induced remarkable changes in most volatiles, particularly for a decrease in aldehydes, and a small incorporation of terpenoids. Orthogonal partial least squares-discriminant analysis (OPLS-DA) identified 10, 10, and 12 key markers for distinguishing samples with and without TP. TP addition could reduce the consumption of amino acids and fatty acids, thereby potentially decreasing the production of their associated flavor metabolites. • QDA and E-nose assess the aroma characteristics of stewed lamb. • Thyme polyphenol extract (TP) additions could modify aroma profile of stewed lamb. • Identification of key markers distinguishing with or without TP samples by OPLS-DA. • TP additions could weak amino acids and fatty acids consumption.