多步逐级裂解技术研究卷烟燃时香味成分形成与温度之间的关系

Relationship Between Volatiles Formation and Temperature During Cigarette Smoking Investigated by Multi-Step Pyrolysis Technology

为了解卷烟燃吸过程中温度对主流烟气香味成分形成的影响以及烟气香味成分形成与烟草前体物的对应关系,采用多步逐级裂解-气质联用分析方法,模拟研究了多步逐级裂解温度对香味成分形成的影响。结果表明:1)多步逐级裂解技术可以很好地用来研究裂解温度对烟叶裂解时所释放的挥发性和半挥发性物质的影响,从而揭示所释放的物质与温度间的关系。2)卷烟燃吸时,250℃以下是游离的香味物质蒸馏释放阶段,释放的挥发性物质相对较少,主要是游离的尼古丁、烟碱烯和新植二烯;300~600℃是烟叶的裂解阶段,其中碳水化合物、氨基酸、色素、色素长链脂肪酸酯、非环状异戊二烯类、西柏烷类物质等前体物在300~500℃裂解形成大量的挥发性和半挥发性物质,蛋白质在600℃降解形成大量含氮杂环化合物;700~900℃是烟叶的碳化和燃烧阶段,主要产物是二氧化碳、一氧化碳等简单气体。3)与裂解相比,烟叶自身可蒸馏的挥发性和半挥发性化合物占比很小(5.74%),高温裂解(300℃及以上)所形成的香味成分可能决定了卷烟的抽吸风格特征。

In order to understand both effects of combustion temperature of cigarettes on the formation of main volatile components in cigarette smoke and the relationship between the volatile compounds formation in cigarette smoke and tobacco precursors, the effects of sequential pyrolytic temperatures on the formation of volatile components were simulated and investigated using the multi-step pyrolysis technology coupled with gas chromatography-mass spectrometry(GC-MS). The results showed that 1) the multi-step pyrolysis technology could be used to well-study the effect of pyrolysis temperature on the volatile and semi-volatile substances released from tobacco during pyrolysis to reveal the relationship between the released substances and temperature. 2) During the combustion of cigarette, the free flavoring substances distillated and released under 250 ℃ with less volatile substances released, which were mainly free nicotine, nicotyrine and neophytadiene. The tobacco cracked within 300~600 ℃, and many volatile and semi-volatile substances were formed when the precursors, i.e., carbohydrates, amino acids, pigments, pigment esters with long-chain fatty acids, acyclic isoprenoids and cembrenoids, cracked at 300~500 ℃. Protein degraded and formed a large amount of nitrogen containing heterocyclic compounds at 600 ℃. The carbonization and combustion of tobacco occurred within 700~900 ℃, mainly producing simple gases such as carbon dioxide and carbon monoxide. 3) Compared with pyrolysis, the proportion of volatile and semi-volatile compounds distilled from cigarette itself was very small(about 5.74%), while the volatile components formed by pyrolysis under high temperature(300 ℃ or above) might determine the aroma style characteristics of cigarettes.