顶空固相微萃取-气质联用法测定不同陈化时间普洱茶香气成分

Determination of aroma components of aged Pu-erh tea with different storage years based on solid phase microextraction-gas chromatography-mass spectrometry

中文关键词:  普洱茶  香气成分  固相微萃取  气质联用

英文关键词:Pu-erh tea  aroma compounds  solid phase microextraction  gas chromatography-mass spectrometry

中文摘要:

      目的 测定不同陈化时间普洱茶的挥发性组分。方法 采用顶空-固相微萃取-气质联用法(SPME-GC/ MS)测定18个普洱茶挥发性物质。结果 从18个普洱茶中共鉴定出98种挥发性物质, 包括14种甲氧基酚类、11种醛类、15种醇类、13种酮类、4种酯类、2种呋喃类、2种含N化合物、35种碳氢化合物及2种其他类物质。陈化时间短(4年)的普洱生茶中醇类(31.01%)和碳氢化合物(22.92%)含量高, 甲氧基酚类化合物含量低(1.3%), 具有明显的晒青毛茶香气特征。陈化时间长(≥25年)的普洱生茶和普洱熟茶聚成一类, 这类普洱陈茶甲氧基酚类化合物含量高(7.52%~39.17%), 且不同陈化时间的普洱茶样本之间香气特征相似, 仅通过香气无法推断其陈化时间。结论 本研究为消费者正确认识和收藏普洱茶提供一定的参考依据。

英文摘要:

      Objective To study the volatile compounds of different aged Pu-erh teas. Methods The volatile components were analyzed by solid phase microextraction (SPME) combined with gas chromatography-mass spectrometry (GC-MS). Results It showed that a total of 98 volatile compounds were identified by matching EI mass spectra and retention indices with the literature data, including 14 methoxy-phenolic, 11 aldehydes, 15 alcohols, 13 ketones, 4 esters, 2 furans, 2 N-containing compounds, 35 hydrocarbons and two others compounds. Aged Pu-erh tea with short storage year (4 years) contained a lot of alcohols (31.01%) and hydrocarbons (22.92%), while the content of methoxy-phenolic compounds was low (1.3%), which exhibited drying green raw tea aroma characteristics. Aged Pu-erh raw tea with long storage year (≥25 years) were gathered into a class with Pu-erh ripened tea, which contained high levels of methoxy-phenolic compounds (7.52%~39.17%), and the aroma characteristics of different Pu-erh teas were similar, which indicated that it was difficult to deduce the concrete storage year of aged Pu-erh raw tea according to the aroma characteristics solely. Conclusion This study provides useful information to objectively evaluate the quality and commercial value of aged Pu-erh teas with different storage years.