Cooking improves food aroma, but few studies have explored how cooking affects food aromas. Here, aroma changes in mildly salted large yellow croaker (Larimichthys crocea, MSLYC) after steaming, baking, frying, and deep frying was investigated. The raw fish was dominated by fishy notes but after cooking, the aroma became dominated by fatty notes. Nine volatiles, including hexanal, nonanal, (E, Z)-2, 6-nonadienal, (E, E)-2, 4-decadienal, 1-octen-3-ol, linalool, ethyl hexanoate, acetic acid and anethole, were identified as key odor-active compounds using GC-MS, OAV, and omission tests analyses. Changes in the concentrations of key odor-active compounds were mainly due to evaporation, oxidation of linolenic acids, and thermal catalyzed reactions. Interestingly, anethole was the key odor-active compound, providing new insight into the underlying reactions of cooked fish aroma.
