基于GC-IMS和HS-SPME-GC-MS的不同处理方式分析黑枣挥发性成分

以壶瓶枣为原料，采用三蒸三制、外源美拉德反应液、三蒸三制＋外源美拉德反应液、外源多酚氧化酶、三蒸三制＋外源多酚氧化酶液5 种方式处理制备黑枣，利用气相离子迁移谱（gas chromatography-ion mobility spectrometry，GC-IMS）技术和顶空固相微萃取结合气相色谱-质谱（headspace solid phase microextraction-gas chromatography-mass spectrometry，HS-SPME-GC-MS）联用技术测定黑枣产品挥发性成分，并对结果进行主成分分析和聚类分析，分析不同处理对黑枣风味品质的影响。结果表明：不同处理方式得到的主要挥发性成分各不相同，GC-MS和GC-IMS两种检测方法检出的基础风味物质种类基本一致，共有风味物质为6～10 种。不同处理方式检测到6 种黑枣中均含有糠醛、庚醛、壬醛、正辛醛、冰醋酸。三蒸三制处理可以增加黑枣的风味。同时说明，GC-IMS技术可应用于快速鉴定和差异分析不同黑枣样品挥发性成分，为改进黑枣加工工艺及褐变机制提供理论依据。

Analysis of Volatile Organic Compounds in Black Jujube by Heaspace-Gas Chromatography-Ion Mobility Spectrometry and Headspace Solid Phase Microextraction-Gas Chromatography-Mass Spectrometry

Black jujube was prepared from fresh jujube (Zizyphus jujuba cv. Huping) fruit by five different processes, namely three cycles of steaming and roasting (1), soaking in Maillard reaction products (MRPs) solution, incubation under constant temperature and humidity conditions and roasting (2), soaking in MRPs solution and three cycles of steaming and roasting (3), soaking in polyphenol oxidase (PPO) solution, incubation under constant temperature and humidity conditions and roasting (4), and three cycles of steaming and roasting, soaking in PPO solution, incubation under constant temperature and humidity conditions and roasting (5). The volatile components of black jujube were determined by gas chromatography-ion mobility spectrometry (GC-IMS) and headspace solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS), and the data were analyzed by principal component analysis (PCA) and cluster analysis (CA) to evaluate the effect of different processes on the flavor quality of black jujube. The results showed that the major volatile components of the as-prepared samples were different. The types of basic flavor substances detected by GC-MS and GC-IMS were basically the same, and 6–10 flavor substances were detected by both methods. Furfural, heptanal, nonal, n-octanal and glacial acetic acid were detected in all black jujube samples. Three cycles of steaming and roasting could enhance the flavor of black jujube. Furthermore, this study demonstrates that GC-IMS can be used to quickly identify and analyze the volatile components of different black jujube samples, which provides a theoretical basis for improving the processing technology of black jujube and understanding its browning mechanism.