This study aimed to characterise the volatiles that contribute to stale odour of green tea. Volatiles were extracted using headspace solid‐phase microextraction (HS‐SPME) and analysed using gas chromatography‐mass spectrometry (GC‐MS) and gas chromatography‐olfactometry (GC‐O). Results showed that a total of ninety‐six volatiles were identified by GC‐MS, in which forty‐four volatiles were screened out based on Principal component analysis (PCA) and orthogonal projections to latent structures–discriminant analysis (OPLS‐DA), and thirty‐nine volatiles had a significant variation at the level of 0.05 by analysis of variance (anova). From GC‐O analysis, fifty‐four aromatic volatiles with strong aroma intensity (aroma intensity above 2) were perceived. Further investigation revealed that fifteen volatiles, including 1‐octen‐3‐ol, benzyl alcohol, benzaldehyde, safranal, β‐cyclocitral, (E,E)‐3,5‐octadien‐2‐one, (Z,E)‐3,5‐octadien‐2‐one, dimethyl adipate, dihydroactinidiolide, β‐ionone, α‐ionone, geranyl acetone, phenylethyl alcohol, methyl decanoate and α‐terpineol were responsible for stale odour, besides the former nine compounds were only found in stored tea.

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研究挥发性化合物对绿茶陈旧气味的贡献

这项研究旨在表征导致绿茶陈旧气味的挥发物。使用顶空固相微萃取（HS-SPME）提取挥发物，并使用气相色谱-质谱（GC-MS）和气相色谱-嗅觉法（GC-O）进行分析。结果表明，通过GC-MS鉴定出总共96种挥发物，其中基于主成分分析（PCA）和对潜在结构的正交投影-判别分析（OPLS-DA）筛选出了44种挥发物，以及通过方差分析（方差分析），三十九种挥发物在0.05的水平上有显着变化）。从GC-O分析中，可以看出有54种具有强烈香气强度（香气强度高于2）的芳香族挥发物。进一步的研究表明，有15种挥发物，包括1-辛烯-3-醇，苯甲醇，苯甲醛，黄fra，β-环柠檬酸，（E，E）-3,5-辛二烯-2-（1，（Z，E）-3） ，5-辛二烯-2-酮，己二酸二甲酯，二氢actinidiolide，β-紫罗兰酮，α-紫罗兰酮，香叶基丙酮，苯乙醇，癸酸甲酯和α-松油醇是造成陈旧气味的原因，除了前九种化合物仅在储存中发现茶。