桂花品种‘堰虹桂’‘玉玲珑’和‘杭州黄’的香气成分及释放节律

Flower scent composition of Osmanthus fragrans 'Yanhong Gui' 'Yu Linglong' and 'Hangzhou Huang', and their emission patterns

采用固相微萃取和气相色谱-质谱联用技术分析了桂花Osmanthus fragrans‘堰虹桂’‘Yanhong Gui’‘玉玲珑’‘Yu Linglong’和‘杭州黄’‘Hangzhou Huang’芳香物质及其释放节律。结果表明:3个桂花品种最主要的特征香气物质均为芳樟醇、α-紫罗兰酮和β-紫罗兰酮。随花的开放,3个品种中芳樟醇的香气值均逐渐升高,在盛开期达到最大后降低,α-紫罗兰酮表现为逐渐降低;β-紫罗兰酮在‘堰虹桂’和‘杭州黄’中逐渐降低,在‘玉玲珑’中先升高再降低;此外,部分酯类和烯类芳香物质的相对含量也表现为随花开放而逐渐升高。通过感官判断可知,‘堰虹桂’香气甜而淡,‘玉玲珑’浓香馥郁,‘杭州黄’香甜雅致。花开放过程中主要特征香气物质香气值变化规律的不同与部分品种特异的酯类(γ-癸内酯)和烯类芳香物质(顺式和反式氧化芳樟醇)的共同作用是导致3个桂花品种香气及其释放节律差异的主要原因。

To interpret the fragrance type of different cuhivars in Osmanthus fragrans, flower scent components and emission patterns in ＇Yanhong Gui＇ , ＇Yu Linglong＇ , and ＇Hangzhou Huang＇ were analyzed by means of solid-phase microextraction （SPME） coupled to gas chromatography-mass spectroscopy （GC-MS）. Results showed that the major characteristic scent compositions are similar among three cuhivars including linalool, ct-ionone and β-ionone, while the relative content were different. For all cultivars, the odour activity values （OAVs） of linalool reached a peak at full-blossoming stage then decreased gradually; whereas, OAVs of β-ionone decreased gradually with the flower opening. For ＇Yanhong Gui＇ and ＇ OAVs of β-ionone decreased gradually during flower opening, and in ＇Yu Linglong＇ Hangzhou Huang＇ a low-high-low pattern emerged. In addition, the relative content of some terpene and ester components increased gradually during flower opening. Special scent components such as T-Decalactone, cis-Linalool oxide, and trans-Linalool oxide were also noted. According to sensory judgment, ＇Yanhong Gui＇ had a light and sweet fragrance, ＇Yu Lin- glong＇ had a strong and sweet fragrance, and ＇Hangzhou Huang＇ had an elegant and fresh fragrance. Thus, the major characteristic scent components were similar among the three cultivars, but variations in OAVs for the characteristic scent compositions during flower opening and the appearance of some special scent compo- nents for certain cuhivars most likely caused differences in scent fragrance and emission patterns. [Ch, 5 fig. 4 tab. 34 ref. ]