GC-MS结合化学计量法分析不同干燥方式对黄花菜风味物质的影响

Analysis of effects of different drying methods on flavor substances of daylily using GC-MS combined with a stoichiometric method

为研究干燥方式对黄花菜挥发性风味物质的影响,利用顶空固相微萃取-气相色谱-质谱联用技术对自然干燥、热风干燥和真空脉动干燥的黄花菜样品进行挥发性成分分析,并进一步结合化学计量方法进行判别分析。结果表明,从自然干燥、热风干燥和真空脉动干燥分别鉴定出49、40和44种挥发性化合物,包括醇类、醛类、酮类、烷烃类、烯类、酯类、酸类和其他类化合物共八类成分,其中醛类物质(含量25%)为自然干燥样品中主要挥发性成分,烷烃类物质(含量53%与58%)分别为热风干燥和真空冷冻干燥样品中主要挥发性成分,不同干燥方式制得的黄花菜主要挥发性成分含量存在显著性差异。对不同干燥方式制得的黄花菜样品挥发性化合物进行偏最小二乘判别分析、香气活性值和主成分分析,得出3-呋喃甲醛、3-辛烯-2-酮、十六烷、乙酸为自然干燥特征风味物质,(E)-2-甲基-2-丁烯醛、3-辛烯-2-酮、十六烷为热风干燥特征风味物质,(E)-2-甲基-2-丁烯醛、β-月桂烯为真空脉动干燥特征风味物质。从获得良好风味物质角度出发,真空脉动干燥可得到较好的干制黄花菜,为黄花菜干燥加工提供理论依据。

To illuminate the effect of drying methods on the volatile flavor compounds of daylily,three dried daylily samples were obtained by natural drying,hot air drying,and vacuum pulsating drying,separately,and their volatile components were analyzed by electronic nose and headspace solid-phase microextraction combined with gas chromatography-mass spectrometry(HS-SPME-GC-MS).The data gained was further combined with stoichiometric methods for discriminant analysis.Results showed that 49,40,and 44 volatile compounds were identified from natural drying,hot air drying,and vacuum pulsating drying,respectively,including alcohols,aldehydes,ketones,alkanes,alkenes,esters,acids,and other compounds.In detail,aldehydes(25%)were the main volatile components in natural drying samples.Alkanes(53%and 58%)were the main volatile components in hot air drying and vacuum pulsating drying samples.There were significant differences in the content of the main volatile components of daylily treated by different drying methods.The volatile compounds of daylily samples treated by different drying methods were analyzed by partial least-squares discriminant analysis,odor activity value,and principal component analysis,the results showed that 3-furaldehyde,3-octen-2-one,hexadecane,and acetic acid were the characteristic flavor substances in natural drying samples,(E)-2-methyl-2-butenal,3-octen-2-one,and hexadecane were the characteristic flavor substances in hot air drying samples,(E)-2-methyl-2-butenal andβ-myrcene were the characteristic flavor substances in vacuum pulsating drying samples.From the perspective of getting good flavor substances,vacuum pulsating drying can obtain better dried daylily,which provides a theoretical basis for the drying process of daylily.