Identification of key volatiles responsible for aroma changes of egg white antioxidant peptides during storage by HS-SPME-GC-MS and sensory evaluation

The present study detects the volatiles of egg white antioxidant peptides (EWAPs) with molecular weight range from 1 to 3 kDa and identifies the key volatiles responsible for the aroma changes under different storage conditions using HS-SPME-GC-MS and sensory evaluation. In comparison, the original samples and samples stored at 4 °C and 50% relative humidity (RH), 4 °C and 75% RH, 25 °C and 50% RH, 25 °C and 75% RH, presented 24, 27, 27, 28 and 30 major volatiles, respectively. The cluster analysis and principal component analysis (PCA) both showed that storage environment had a significant effect on the aroma changes. The sensory evaluation demonstrated that EWAPs stored at the same temperature had similar aroma profiles and the samples stored at a higher RH 75% had much stronger aroma intensity, because high temperature and RH may be more suitable to promote some chemical reactions. In Addition, the sensory evaluation of EWAPs samples and the verification experiment about contributions of volatiles, temperature and RH to the changed aroma were conducted, the results further revealed that 3-ethyl-2,5-dimethyl-pyrazine and benzothiazole may be the key volatiles responsible for aroma changes. The results attained in this study may help to explore the methods to prevent or retard the deterioration, and it is also expected to contribute to further research on the stabilization and productization of EWAPs as nutritional and functional food.