释香过程中茉莉净油组成与含量变化规律研究

Studies on the Changing Low to Constituents and Content of Jasmine's Essential Oil during Blooming

有机溶剂浸提制备茉莉净油,经GC、GC/MS分析,内标法定量,鉴定了27个主要组分。组分中由苯甲醇、苯甲酸、顺-3-己烯醇为基本结构单元酯类化合物种类较多且含量高;与头香相比,净油中还含有脂肪酸及其甲酯、苯甲酸苯甲酯等5个高沸点组分;释香过程中,净油、酯类、Ⅱ区组分总量和主要香气组分含量呈低-高-低变化趋势,而醇类、Ⅰ、Ⅲ区组分含量变化与之相反;6种组分与净油香气浓度变化呈显著正相关;用香气品质指数AI(∑Ⅱ/∑Ⅰ+Ⅲ)评价了净油品质,具正常茉莉花香特征的香精油AI值以大于2.5为宜。提出了茉莉花酯类香气组分形成的可能途径。

The absolute oil prepared by organic reagent from jasmine flowers through blooming are analyzed by C-C/MS and GC with interior-standard quantitative method and 27 compounds are identified. Many esters with high level are derived from benzyl alcohol, benzoic acid and cis-3-hexen-l-ol. There are 5 high-boiling-point compounds in absolute oils but not existing in headspace. The content of oils, esters, Ⅱ region and main aroma compounds show the tendency of low-high-low. But the content of alcohols, Ⅰ and Ⅲ region compounds show reverse tendency. 6 compounds are relative to aroma concentration. The index （AI） for evaluating aroma quality is presented. The index value of absolute oil with jasmine aroma characteristic is larger than 2.5. In addition, possible synthetic pathway of esters is proposed.