The comparative aroma extract dilution analysis (cAEDA) applied to the volatile fractions of two types of fresh mint leaves (Peppermint and Spearmint) revealed 20 odor-active peaks with high FD factors (≥64). Among the perceived odorants, five "sweet/milky" and "caramel-like/spicy" notes showing high FD factors were characteristic for the peppermint aroma, and were identified as p-menthane lactone derivatives. Especially, the three p-menthane lactone derivatives, "rel-(3S,3aS,6R,7aS)-dihydromintlactone, (3S,3aS,6R)-epoxymenthofurolactone, and 2E-ethylidene-5-methylcyclohexanone", were newly identified compounds in the peppermint. The biosynthetic routes of the p-menthane lactone derivatives have been suggested to be closely related to menthofuran. Therefore, these findings strongly suggest the possibility that the biosynthetic pathway leading to the p-menthane lactone derivatives via menthofuran plays a significantly important role in the formation of the characteristic aroma of peppermint.

中文翻译：

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鉴定出负责新鲜薄荷叶特征香气的新型气味活性化合物“对薄荷烷内酯”。

比较香气提取物稀释分析（cAEDA）对两种类型的新鲜薄荷叶（薄荷和留兰香）的挥发性成分进行分析，发现20个具有较高FD因子（≥64）的气味活性峰。在感知到的增香剂中，显示出高FD系数的五种“甜/乳状”和“焦糖状/辛辣”香型是薄荷香气的特征，并被确定为对薄荷烷内酯衍生物。特别地，三种对-薄荷烷内酯衍生物“ rel-（3S，3aS，6R，7aS）-二氢薄荷内酯，（3S，3aS，6R）-环氧呋喃内酯和2E-亚乙基-5-甲基环己酮”是新鉴定的化合物。薄荷。对-薄荷烷内酯衍生物的生物合成途径已被认为与薄荷草醚密切相关。所以，