中文摘要：

为了开发热稳定型香原料，采用热重分析／同步差热分析法（TGA／SDTA）、差示扫描量热法（DSC）和在线热裂解气相色谱质谱法（Py—GC—MS）对叶醇糖苷的热降解行为及产物进行了研究．TG—DTC曲线显示主要失重区间在230—370℃，峰值为339．8℃，总失重96．9％；DTA显示在290—360℃有一个吸热峰，峰值为339．8℃；DSC显示230～340℃为吸热区间，峰值为301．3℃；Py—GC—MS测定了在200，350，500，650℃各温度下叶醇糖苷裂解的主要产物．在200℃，裂解量很少，350℃时则产生大量的叶醇和少量副产物，随着温度的升高，500℃和650℃时产生的副产物增加，使叶醇糖苷释放叶醇的最佳温度是350℃；热裂解的特征产物是叶醇，说明主要的裂解反应是氧糖苷键的断裂．

英文摘要：

To develop thermally stable flavor, the thermal decomposition process and pyrolysis products of the leaf alcohol-β-D-glucopyranoside（LGLY） were investigated by thermo-gravimetric and simultaneous differential thermal analysis （TGA/SDTA）, differential scanning calorimeter （DSC） and on-line pyrolysis-gas chromatography-mass spectroscopy （Py-GC-MS）. The TG-DTG curve showed that between 230 -370 ℃ with Tp of 339, 8 ℃ , the largest weight loss rate occurs, and the total weight loss was 96, 9%. The DTA curve illustrated a temperature change between 290 - 360 ℃ , with peak of 339.8 ℃. And Tp measured by DSC was 301.3 ℃ in the endothermic range 230 -340 ℃. Py-GC-MS was used to measure the pyrolysis products at 200, 350, 500 ℃ and 650 ℃. The results indicated that： there was little glycoside degradation at 200 ℃ , but a large amount of leaf alcohol and few by-products were produced at 350 if2 with the increase of temperature; the by-products were significantly increased at 500 ℃ and 650 ℃ ; the optimized temperature was 350 ℃ for LGLY to release the specific flavor of leaf alcohol ; the characteristic pyrolysis product was leaf alcohol. The primary decomposition reaction was the cleavage of O-glycosidic bond of the glycoside flavor precursors. The study showed that this kind of flavor precursors were used to provide the product specific flavor during heating process.