不同紫胶原料及产品挥发物的化学成分分析

Analysis of Volatile Chemical Components in Different Lac Materials and Products

为提高紫胶产品质量,避免嗅觉异味,采用动态顶空密闭循环吸附法和热脱附-气相色谱/质谱(TCT-GC/MS)联用技术对紫胶原胶、颗粒紫胶、常温干燥法漂白紫胶、真空冷冻干燥法漂白紫胶、热挤干燥法漂白紫胶的挥发物进行捕集和分析检测。结果表明:不同紫胶原料及产品的挥发物化学成分以苯系物为主,所占比例分别达各自挥发物总量的90%、90%、60%、30%、80%以上;由于除杂、干燥等原因,不同紫胶原料及产品中的挥发物检出种类及数量有不同程度增减,漂白加工对紫胶挥发物无明显影响;紫胶生产利用中应注意选择合理技术以减少挥发性异味。

In order to improve the quality of lac products and avoid odor, volatile components from 5 different lac raw materials and final products were trapped by a dynamic head-space closed cycle adsorption method and analyzed by thermal cryo-trapping-gas chromatography/mass spectrometry （TCT-GC/MS）. Results showed that benzene homologues were predominant, which were over 90% in volatile components from lac raw materials, over 90% from seed lac, over 60% from bleached shellac dried at room temperature, over 30% from lyophilized bleached shellac and over 80% from heating-crushed bleached shellac. Volatile chemical components in different raw materials and final products were also different due to various purification and drying styles. No significant change in volatile components was observed during bleaching of lac. Therefore, proper techniques will be benefited for avoiding odor during lac processing and utilization.