MAE-SAFE-GC×GC/HR-TOFMS法鉴定熟制中华绒螯蟹挥发性风味成分

Identification of Chinese mitten crab volatile compounds based on MAE-SAFE-GC×GC/HR-TOFMS

摘要:

采用微波辅助萃取耦合溶剂辅助风味蒸发法（MAE-SAFE）提取中华绒螯蟹两大可食部位—体肉（不含足钳肉），性腺（含肝胰腺）的挥发性风味成分，并应用全二维气相色谱-高分辨飞行时间质谱技术（GC×GC/HR-TOFMS）结合保留指数及精确质量数进行香气定性分析。共鉴定出122种挥发性成分，60种物质经精确质量数二次定性，在同原料研究中检出种类最多。其中性腺检出108种化合物，体肉75种，性腺中具有更为丰富的醛类，酮类及含氮类化合物。MAE-SAFE法获得的20种酮类、27种醇类、7种含氮类，4种含硫类化合物，使得其对该类极性热敏性挥发性成分化合物具有其他前处理方法所不具有的富集优势，温和快速的加热萃取方式保证了所获香气成分的真实性。GC×GC/HR-TOFMS的高分辨率和高峰容量使得（E）-2-戊烯-1-醇与（Z）-2-戊烯-1-醇等多种同分异构体实现完全分离，甲酰胺（氨味），麦芽酚（焙烤样香）及其前体物4H-2，3-二氢-3，5-二羟基-6-甲基吡喃-4-酮为首次在中华绒螯蟹中检出，为后续进行关键香气成分的筛选提供了可靠全面的香气成分信息。

Abstract:

Microwave-assisted extraction combined with solvent assisted flavor evaporation(MAE-SAFE) was applied to extract the volatiles from two edible parts of Chinese mitten crab, abdomen meat and gonad part. The volatiles were quantitatively analyzed by the comprehensive two-dimensional gas chromatography/high resolution-time of flight mass spectrometry (GC×GC/HR-TOFMS), and identified by the retention index with an aid of the NIST11 library. A total of 122 volatile compounds were identified, which is the largest identification number among similar researches of same material, and 60 compounds were double identified by the accurate mass (AM) determination. More aldehydes, ketones, nitrogen-containing compounds in gonad part with total of 108 compounds were identified, while only 75 volatiles were identified in abdomen meat. MAE-SAFE has a better effect on the extraction of polar thermo-sensitive volatile compounds than other volatile enrichment method, and 20 ketones, 27 alcohols, 7 nitrogen-containing compounds, 4 sulfur-containing compounds were identified. The gentle and rapid heating method ensures the authenticity of the aroma components. GC × GC/HR-TOFMS with high resolution and high peak capacities enabled isomeric compounds like (E) -2-penten-1-ol and (Z)-2-penten-1-ol to achieve full separation. Compounds like formamide (ammonia flavor), maltol (baking-like flavor) and its precursor 4H-2,3-dihydro-3,5-dihydroxy-6-methylpyran-4-one were first detected in Chinese mitten crab. Therefore, this study provides comprehensive and reliable volatile component information for subsequent screening of key aroma compounds.