不同盐度条件下鱼露发酵前期挥发性风味物质的指纹图谱

为探明一定盐度条件下传统鱼露发酵前期挥发性风味物质随时间变化的规律,建立鱼露发酵前期挥发性风味物质的指纹图谱及明确主要风味物质。采用气相色谱—质谱联用(GC-MS)方法分析了180和230两种盐度条件下日本鰒鱼露发酵液的挥发性风味成分。结果显示,有80%的鱼露样品相似度良好,与对照图谱相似度达到了90%;180盐度下发酵150 d的鱼露挥发性风味物质变化较大。盐度180发酵的鱼露样品组有51个共有峰,盐度230有58个共有峰,并在对照图谱中加以标定。通过对指纹图谱共有峰化合物指认,确定了乙醇、丙酮、异戊醛、1-戊烯-3-醇和2-甲基丁酸为鱼露前期发酵液的主要挥发性风味物质。研究表明,盐度180发酵的鱼露更早地进入基础物质转化阶段,有利于鱼露海鲜味的生成;230盐度发酵的鱼露整体发酵进程较为缓慢,但更有利于鱼露中乳酪味和肉香味的形成。在实际生产中可根据需要选择不同的盐度进行发酵。研究结果为揭示鱼露发酵前期主要基础挥发性风味物质及变化规律和鱼露品质控制等提供科学依据。

Volatile flavor compounds fingerprints during fish fermentation at different salt concentrations

The main volatile flavor compounds of fish sauce were determined in order to investigate their changes and establish the fingerprints of volatile flavor compounds during pre-fermentation of fish sauce and clarify the main flavor compounds under 18% and 23% salinity. The volatile flavor compounds in samples were analyzed by gas chromatography-mass spectrometry (GC-MS) in the fermentation process. The results showed that the similarity of eight samples of fish sauce was good and reached 90% compared to the control. The volatile flavor compounds of the fish sauce was changed significantly at 18% salt concentration for 150 days. The fish sauce fermented with 18% salinity (YD1) group gained 51 common peaks and 58 as the fish sacue fermented with 23% salinity (YD2) group. All of those common peaks were calibrated to their respective reference fingerprint. Ethanol, acetone, isovaleraldehyde, 1-penten-3-ol and 2-methylbutyric acid were identified as the main volatile compounds in the pre-fermentation of fish sauce by the identification of the common peaks of the fingerprints. Comparing with the five volatile flavor compounds, YD1 group occurred earlier in the basic material transformation stage, at least 2 months than YD2 group. The results can provide effective references for revealing the regularity of main volatile flavor compounds and the quality control of fish sauce.