Effects of pre-ultrasonication on small molecular metabolites and flavour compounds in chicken broth

The chicken broth was pre-treated with ultrasound at 0, 480, 600, 720 and 840 W for 30 min before stewing, and the changes of free fatty acids, small molecular compounds, volatile flavour compounds, umami polypeptides in the chicken broth were determined by GC-MS, UPLC-Q-Exactive-MS, GC-IMS and LC-MS/MS, respectively. 600 W ultrasonic treatment group outperformed the other groups in terms of sensory evaluation (P < 0.05). Palmitic acid and stearic acid were the chief free fatty acids in chicken broth. 530 and 236 small molecule metabolites were found. 36 volatile compounds were identified in chicken broth, mainly aldehydes. The proportion of sweet and umami amino acids in the chicken broth of the 600 W ultrasonic treatment group accounted for 63% of the total polypeptide sequence, indicating that pre-ultrasonication can increase the content of sweet and umami polypeptides in chicken soup. The overall taste and flavour of Wuding chicken soup under pre-ultrasonication with 600 W power were the best combined with sensory evaluation scores. These results can provide scientific and theoretical guidance for the further understanding of the effect of ultrasound assistance on the quality of chicken broth and the intensive processing of local chicken.