基于顶空固相微萃取-气相色谱-质谱法分析不同嫩度河红茶香气的差异

Analysis of characteristic aroma components of different tenderness of Hekou black tea based on headspace solid-phase microextraction- gas chromatography-mass spectrometry

中文关键词:  河红茶  顶空固相微萃取-气相色谱-质谱法  不同嫩度  香气组分

英文关键词:Hekou black teas  headspace solid-phase microextraction-gas chromatography-mass spectrometry  different grades  aroma components

中文摘要:

      目的 了解不同嫩度河红茶特征香气组分情况。方法 利用顶空固相微萃取结合气相色谱-质谱法, 对同一品种制作的不同嫩度的河红茶的香气组分进行分析。结果 河红茶中共检测并鉴定出68种香气成分。醇类、酸类、醛类、酮类、酯类、烯类、杂环类化合物相对含量分别为14.03%~19.47%、1.29%~3.31%、3.64%~11.81%、0.94%~2.99%、10.29%~17.37%、1.43%~3.01%、4.03%~5.92%, 烷、萘及其他类化合物总相对含量低于0.66%。不同的嫩度的河红茶香气物质含量及组成比例不尽相同; 香气化合物的含量也随着新梢嫩度的降低而提高, 香气成分含量以一芽三叶河红茶(T4)最优。通过正交偏最小二乘判别分析分析发现, 不同嫩度河红茶关键性成分分别为: 水杨酸甲酯、芳樟醇、苯乙醇、苯甲醇、己酸顺式-3-己烯酯、苯乙醛、α-法呢烯、苯甲醛、γ-杜松烯、(E)-3,7-二甲基-2,6-辛二烯酸、癸酸乙酯、3-己烯-1-醇、反式氧化芳樟醇(呋喃类)、壬醛、β-紫罗兰酮、反式氧化芳樟醇(吡喃类)、己酸己酯、α-蒎烯。结论 不同嫩度河红茶呈现不同变化的关键性香气物质, 主要表现为花香、果香、青香、甜香等。以上结果阐明了河红茶香气成分分级指标, 为实现河红茶香气品质客观评价提供了参考。

英文摘要:

      Objective To understand the changes in the aroma components during different grades of Hekou black teas. Methods Headspace solid-phase microextraction combined with gas chromatography-mass spectrometry was used to analyze the aroma components of Hekou black teas made from the same tea plant variety. Results The results showed that a total of 68 kinds of aroma compounds was detected and identified. The relative contents of alcohols, acids, aldehydes, ketones, esters, alenes and heterocyclic compounds were 14.03%?19.47%, 1.29%?3.31%, 3.64%?11.81%, 0.94%?2.99%, 10.29%?17.37%, 1.43%-3.01%, 4.03%?5.92%, respectively, and the total relative content of alkane, naphthalene and other compounds were lower than 0.66%. The content and composition ratio of aroma substances in different grades of Hekou black teas were not the same. The content of aroma compounds also increased with the decrease of shoot tenderness, and T4 was the excellent. Through orthogonal partial least squares discriminant analysis and Filter variance variables analysis, it was found that the key ingredients of different grades of river black tea were: Methyl salicylate, linalool, phenylethyl alcohol, (Z)-3-hexanoic acid hexenyl ester, phenylethyl alcohol, α-farnesene, benzaldehyde, (+)-γ-cadinene, (E)-3,7-dimethyl-2,6-octadienoic acid, decanoic acid ethyl ester and α-copaene. Conclusion Different Hekou black teas presents different key aroma substances, mainly including flower, fruit, green, sweet, etc.. The above results clarifies the classification index of aroma components of Hekou black teas, which provids a reference for the objective evaluation of Hehei tea aroma quality.