热风干燥和真空冷冻干燥对猴头菇不同部位风味物质的影响

Effects of Hot Air-drying and Vacuum Freeze-drying on Flavor Components in Different Parts of Hericium erinaceus

为探究猴头菇干燥前后风味特征的变化,本研究以新鲜猴头菇为原料,利用高效液相色谱(HPLC)技术和气相离子迁移谱(GC-IMS)技术测定并比较了热风干燥和真空冷冻干燥对猴头菇菇盖和菇柄风味物质的影响。结果表明,新鲜猴头菇经两种方式干燥后,可溶性糖、5’-核苷酸、游离氨基酸的含量均显著降低(P<0.05),其中热风干燥样品损失最多;不同猴头菇样品中有机酸总量为真空冷冻干燥样品>热风干燥样品>新鲜样品;经GCIMS共鉴定出猴头菇鲜样和干样中64种挥发性风味物质,主要为醇类(17种)和醛类化合物(14种),其次为酮类(11种)和酯类(10种)化合物,总体来看,真空冷冻干燥更有利于保留猴头菇中八碳化合物以及其他醇、醛类风味物质,而热风干燥更易于形成酮、酯类化合物。干燥前后猴头菇菇盖中总可溶性糖、总5’-核苷酸及总游离氨基酸的含量显著高于菇柄(P<0.05),而总有机酸含量呈相反趋势,菇盖和菇柄挥发性风味物质指纹图谱的变化趋势一致。本研究可为猴头菇加工产品的开发提供理论依据。

In order to explore the changes of flavor characteristics of Hericium erinaceus before and after drying,the effects of hot air-drying and vacuum freeze-drying on flavor components of pileus and stipe of H.erinaceus were studied using high performance liquid chromatography(HPLC)and gas chromatography-ion mobility spectrometry(GC-IMS)in this paper.The results showed that the contents of soluble sugar,5’-nucleotide and free amino acid in H.erinaceus significantly decreased after drying(P<0.05).And the loss of them in hot air-drying samples was higher than that of vacuum freezedrying samples.The total content of organic acids in different H.erinaceus samples increased in the order of vacuum freeze-drying samples>hot air-drying samples>fresh samples.A total of 64 volatile compounds in fresh and dried H.erinaceus were detected by GC-IMS,mainly alcohols(17)and aldehydes(14),followed by ketones(11)and esters(10).In general,vacuum freeze-drying was more conducive to retain eight carbon atom(C8)compounds and other alcohols and aldehydes of H.erinaceus than hot air-drying,while hot air-drying was easier to form ketones and esters than vacuum freeze-drying.Meanwhile,the content of total soluble sugar,total 5’-nucleotides and total free amino acids in the pileus was significantly higher than that of stipe(P<0.05),but the total content of organic acids was on the contrary.The variation trend of volatile compounds fingerprint spectra of pileus consists with that of stipe.This study provided reference for the processing of the H.erinaceus.