Effects of Different Extraction Processes on the Physicochemical Properties and Volatile Flavor Compounds of Chicken Oil

The color, extraction rate, peroxide value, acid value and malondialdehyde of chicken oil extracted by the dry method extraction, wet method extraction and microwave-assisted extraction processes were comprehensively compared. The results showed that the color of chicken oil boiled by microwave was reddish, with a lighter yellow color, higher extraction rate, better oxidation stability, and shorter time. The volatile flavor compounds of chicken oil were analyzed by headspace gas chromatography-mass spectrometry (GC-MS). The results showed that a total of 49 volatile flavor compounds were identified in chicken oil samples from different extraction processes, including 41 volatile flavor compounds in wet method extraction of chicken oil, 39 volatile flavor compounds in dry method extraction of chicken oil, 44 volatile flavor compounds in microwave-assisted extraction of chicken oil, 30 common volatile flavor compounds. The ROAV and PCA methods were conducted to identify (E,E)-2,4-heptadienal, 1-octen-3-ol, nonaldehyde, 1-octene-3-one, (E)-2-decenal, 1-pentanol, (E,E)-2,4-decadienal, 3-methylbutyraldehyde, as the main characteristic flavor substances of chicken oil. Besides, chicken oil extracted by microwave-assisted method showed the highest content of the key aroma components. The clustering heat map indicated a significant color difference among the chicken oil samples prepared by different processes, indicating that it was feasible to distinguish chicken oils prepared by different processes based on volatile flavor compounds.