Analysis of Volatile Flavor Compounds in Three Types of Baked Fish Fillets Using an Electronic Nose Combined with GC-IMS

In order to compare the flavour differences between cod, monkfish and eel fried fish fillets, this paper measured the volatile organic compounds of the three fried fish fillets with an instrument, and performed statistical analysis and sensory evaluation. The results showed that the electronic nose sensor was more sensitive to sulphide in the VOCs of fried fish fillets, with eel fillets>monkfish fillets>cod fillets. A total of 72 VOCs were detected by gas phase ion mobility spectrometry in the three types of grilled fish fillets, including 9 aldehydes, 10 alcohols, 6 ketones, etc. Thirteen VOCs with relative odour activity value (ROAV)≥1 were identified as the major flavour compounds, among which the marker VOCs common to the three types of grilled fish fillets were 2-ethylfuran (butter flavour) and acetaldehyde (apple flavour). The key VOCs specific to cod fillets were 2-ethylfuran (butter flavour) and acetaldehyde (apple flavour). The key VOCs specific to cod fillets were 2-ethylfuran (butter flavour), acetaldehyde (apple flavour), ethyl 2-methylbutyrate (ester flavour), 2,3-pentanedione (light sweetness), isoamyl acetate (banana flavour), ethylbenzene (petrol flavour), isoamyl alcohol (brandy flavour) and ethanol (aroma flavour), and in eel fillets, the main VOCs identified were 2,3-butanedione (caramel flavour), cis-4-heptenal (milk flavour). The two VOCs specific to monkfish fillets were tert-butanol (camphor flavour) and n-butyraldehyde (fruity flavour) with ROAV values ranging from 0.1 to 1, which contributed to the overall flavour. Variable Importance Projection (VIP) screened out 21 differential VOCs, and the three characteristic VOCs of grilled fish fillets could be well distinguished by principal component analysis. This study contributes to the raw material selection of grilled fish fillets, which is of practical importance to further improve the flavour quality.