采用顶空固相微萃取/气相色谱-质谱联用技术对武夷大红袍初制过程在制叶的香气成分进行了分析,结果表明,与鲜叶相比,以壬醛、十四烷、十三烷、十二烷、丁酸-2-乙基-1,2,3-丙三酯、二-叔-十二烷基二硫化物和乙酸橙花叔酯为代表的烷烃类、醛类和酮类组分等香气成分随着初制工序的进展呈下降趋势,且降幅较大,在毛茶中的含量分别下降了72.4%、91.8%、63.6%;而以橙花叔醇、α-法尼烯、吲哚、苯乙腈、苯乙醇、己酸己酯、己酸-顺3-己烯酯、己酸-反2-己烯酯、苯甲酸己酯、苯甲酸-3-己烯-1-酯和苯甲酸反2-己烯酯为代表的构成大红袍的特征性香型的醇类、酯类和烯烃类香气成分在初制过程中大量转化生成,在毛茶中的含量分别增加了215.5%、70.8%、682.6%。
The aroma components of tea leaves of Wuyi Dahongpao during the preliminary processing were investigated by headspace solid phase microextraction/gas chromatography-mass spectrometry (GC-MS). The results show that compared to the fresh leaves, the aroma component contents of alkanes, aldehydes and ketones such as nonaldehyde, tetradecane, tridecane, dodecane, butyl-2-ethyl-1,2,3-propyltriester, di-tert-dodecyl disulfide and orange blossom tert acetate were decreased drastically during the preliminary processing, which were decreased by 72.4%, 91.8% and 63.6% in the raw made tea, respectively. The alcohol, ester and olefin aroma components such as nerolidol, alpha olefin, indole, phenylacetonitrile, phenylethyl alcohol, caproic acid ester, hexanoic acid-shun 3-hexene ester, hexanoic acid-2-hexene ester and benzoic acid ester, acid-3-hexene-1-ester, and benzoic acid 2-hexene ester were largely increased during the preliminary process. The alcohol, ester and olefin aroma components involved in the characteristic flavor of Dahongpao were increased by 215.5%, 70.8% and 682.6% in the raw made tea respectively.
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