Establishment and Optimization of Analytical Method for Detection of Volatile Flavor Compounds in Dry-Cured Fish

A gas chromatography-mass spectrometric (GC-MS) method was developed for the detection of volatile flavor compounds in dry-cured blunt snout bream. Analytical conditions such as extraction temperature, solid-phase microextraction (SPME) probe, headspace vial, chromatographic column, and extraction techniquewere optimized based on the peak area of identified compounds (hexanal, heptanal, octanal, nonanal, 1-penten-3-ol, 1-pentanol, hexanol and 1-octen-3-ol). The results showed that a total of 85 volatile compounds were detected in dry-cured fish. More volatile compounds were extracted at 90 ℃ than at 40 ℃, indicating that more volatile compounds were produced by thermal reaction. Divinylbenzene-carboxen polydimethylsiloxane (DVB/CAR/PDMS) fiber could better adsorb volatile compounds from dry cured fish. Twenty-mL short headspace vials provided better adsorption efficiency for volatile compounds, but the adsorption efficiency was lower than that of tall headspace vials. The volatile compounds in dry-salted fish were separated better on a polar column with good reproducibility. More aldehydes and alcohols were detected using a DB-WAX column, more acids and esters were detected using an HP-INNOWAX column, and more hydrocarbons were separated using a DB-1 column with weak polarity. The results of headspace solid phase microextraction (HS-SPME), stir bar sorptive extraction (SBSE) or dynamic headspace extraction (DHS) combined with gas chromatography-mass spectrometry (GC-MS) showed that DHS extracted the most volatile compounds, SBSE extracted the least volatile compounds, and SPME provided the most efficient and rapid extraction of volatile flavor compounds. SPME and DHS were more suitable for the extraction of volatile compounds from dry-cured fish.