基于气相色谱-离子迁移色谱分析不同贮藏方式对洋葱浆馕风味的影响

采用气相色谱-离子迁移谱（gas chromatography-ion mobility spectrometry，GC-IMS）对洋葱浆馕6 种不同贮藏条件下挥发性物质进行分析，包括低温贮藏、室温贮藏、真空贮藏、脱氧贮藏、保鲜剂贮藏和保鲜剂结合脱氧贮藏。研究表明：在洋葱浆馕中共鉴定出66 种挥发性风味物质，其中包括醇类9 种、酮类4 种、醛类18 种、酯类4 种、呋喃衍生物3 种，酸类1 种和未能识别的化合物27 种。随着贮藏时间的延长，低温贮藏和真空贮藏洋葱浆馕在贮藏期内醛类挥发性有机物基本不变，其他处理组的醛类挥发性有机物在贮藏期内变化呈降低的趋势。结合主成分分析和欧氏距离可以发现低温贮藏和其他贮藏方式的第0天挥发性物质种类和浓度较为接近，主成分分析图中点的位置也相聚在一起，说明低温贮藏馕的挥发性物质变化不明显。该研究建立不同贮藏方式洋葱浆馕挥发性气味指纹图谱，可视化出洋葱浆馕挥发性成分轮廓，为洋葱浆馕贮藏期间风味变化规律提供信息。

Analysis of the Effects of Different Storage Methods on the Flavor of Onion-Covered Nang,a Baked Flatbread,by Gas Chromatography-Ion Mobility Spectrometry

In this study, gas chromatography-ion mobility spectrometry (GC-IMS) was used to analyze the volatile substances of onion-covered Nang under six different storage conditions, including low-temperature storage, room temperature storage, vacuum storage at room temperature, oxygen-free storage at room temperature, aseptic storage at room temperature, and oxygen-free and aseptic storage at room temperature. The results showed that 66 volatile flavor compounds were identified from onion-covered Nang, including 9 alcohols, 4 ketones, 18 aldehydes, 4 esters, 3 furans, 1 acid and 27 unrecognized compounds. As storage time increased, the content of volatile aldehydes in onion-covered Nang stored at low-temperature and vacuum remained basically unchanged, while the content of volatile aldehydes showed a decreasing trend under the other storage conditions. Principal component analysis (PCA) and Euclidean distance analysis showed that the types and concentrations of volatile substances on day 0 of low-temperature storage were relatively close to those under the other storage conditions, and the positions of the data points in the PCA plot were gathered together, indicating that the change of volatile substances was not obvious under low-temperature storage conditions. This study can provide useful information for understanding the flavor change of onion-covered Nang during storage.