几种干燥方式对金针菇子实体挥发性风味成分的影响

为研究不同干燥方式对金针菇子实体挥发性风味物质的影响,运用固相微萃取（SPME）和气相色谱-质谱（GC-MS）联用技术,分别对金针菇鲜样及热泵、鼓风和真空冷冻三种方式干燥的金针菇挥发性成分进行分析比较。金针菇干样和鲜样共检出54种挥发性成分,其中热泵干燥和鼓风干燥后主要挥发性成分为醛类和醇类,其次为酯类和酮类,热泵干燥后2-甲基丁醛、3-甲基丁醛和2,3-丁二醇相对含量较高,鼓风干燥后3-甲基丁醛和丁内酯较高;真空冷冻干燥后和鲜样中主要挥发性成分为烃类和醇类,真空冷冻干燥后相对含量较高的为2,2,4,6,6-五甲基庚烷、2,3-丁二醇和D-柠檬烯。三种干燥方式中,加热的干燥方式使物料成分发生相互作用生成较多阈值低的风味物质,鼓风干燥因局部反应剧烈还生成吡嗪类物质,真空冷冻干燥因低温无氧条件而能较好保持鲜金针菇风味。 

Influence of drying methods on volatile components of Flammulina velutipe

The volatile composition of Flammulina velutipe by different drying methods (heat pump, hot air and vacuum freeze drying) was analyzed by gas chromatography-mass spectrometry (GC-MS) with solid-phase micro-extraction (SPME) . A total of 54 volatile compounds were detected. By using heat pump and hot air drying, aldehydes and alcohols were the major components in Flammulina velutipe, followed by esters and ketones. Higher relative content of 2/3-methylbutanal and 2, 3-butanediol were observed in the sample by using heat pump, while 3-methylbutanal and butyrolactone were in greater percentage in the one by hot air drying method. On the other hand, hydrocarbons and alcohols showed the highest contents in the sample by vacuum freeze drying method and the control. It demonstrated that 2, 2, 4, 6, 6-pentamethylheptane, 2, 3-butanediol and D-limonene were the major components in the sample by vacuum freeze drying method.Among these drying methods, more volatile compounds which had lower thresholds were generated by heat treatment methods due to the interaction of compounds in raw material. Besides, pyrazines were detected by hot air drying for local heat reactions. With regard to vacuum freeze drying method, the fresh Flammulina velutipe flavor could be better kept due to the low temperature and anaerobic condition.