The Effect of Magnetic Nanoparticles Plus Microwave Thawing on the Volatile Flavor Characteristics of Largemouth Bass (Micropterus salmoides) Fillets

The volatile flavor characteristics of largemouth bass (Micropterus salmoides) fillets thawed by magnetic nanoparticles plus microwave thawing (MNPMT) were compared with those of fresh samples thawed by chill storage thawing (CST) and microwave thawing (MT). The strategies of headspace solid-phase microextraction (HS-SPME), gas chromatography mass spectrometry (GC-MS), gas chromatography-olfactometry (GC-O), aroma extract dilution analysis (AEDA), and sensory evaluation were applied to analyze the aroma-active compounds. The results of GC-MS showed that 24 kinds of volatile compounds existed in largemouth bass fillets. Orthogonal partial least squares discriminate analysis (OPLS-DA) ((RY)-Y-2 = 0.979, (RY)-Y-2 = 0.98, Q(2) = 0.695) showed ethanol, hexanal, 2,6,10,14-tetramethyl-pentadecane, and (E)-9-octadecenoic acid were responsible for the flavor differences in MNPMT, MT, and CST. In GC-O measurement, 14 kinds of volatile compounds were detected, and MNPMT had similar aroma-active compounds with the fresh sample. The grassy (score = 1.58) and leafy (score = 0.75) odors were weak in MT, but the fishy odors (score = 1.5) were strong. All results showed the MNPMT samples had less changes in aroma composition compared with the fresh sample.