Changes in stability and volatile flavor compounds of self-emulsifying chicken soup formed during the stewing process

The influences of stewing times (1, 2, 3, 4, 5, and 6 h) on total sugar, total lipids, water-soluble proteins, ζ-potential, particle size, stability index, microstructure, and volatile compounds of chicken soup were investigated, and the taste and aroma profiles of chicken soup were evaluated using a sensory panel. The results showed the self-emulsifying chicken soup obtained after stewing for 4 h had the highest stability index. The improvement in stability index was connected with the increase of soluble protein and ζ-potential and the decrease of particle size. Optical microscope, confocal laser scanning microscope, and scanning electron microscope observations showed that oil droplets and the particles in the soup were small and uniformly dispersed when the stewing time reached 4 h. Additionally, GC-MS analysis showed that the types and relative percentage contents of volatiles in the chicken soup changed with the extension of stewing time. The flavor composition variation was tending towards stability after stewing for 4 h, and the sensory evaluation results also showed that the scores of umami, saltiness and aroma of chicken soup were no longer significantly increased. In general, a balance between stability and flavor formation of the self-emulsifying chicken soup achieved after 4 h of stewing. This study provided a basic information for high-quality chicken soup.