基于吹扫捕集-气相色谱/质谱法分析豆汁、麻豆腐中风味物质

Analysis of flavor compounds in Douzhir and Ma Tofu based on purge and trap-gas chromatography/mass spectrometry

中文关键词:  豆汁  麻豆腐  吹扫捕集-气相色谱/质谱  风味物质

英文关键词:Douzhir  Ma Tofu  purge and trap-gas chromatography/mass spectrometry  flavor compounds

中文摘要:

      目的 基于吹扫捕集-气相色谱/质谱法(purge and trap-gas chromatography/mass spectrometry, PT-GC/MS)并结合美国国家标准与技术研究院(national institute of standards and technology, NIST)数据库, 鉴定豆汁、麻豆腐中的风味物质并分析其特征物质。方法 称取2.0 g样品, 于40 mL棕色螺旋样品瓶中, 加入10 mL实验用水与四氟磁力搅拌子, 样品加热温度40 ℃, 经PT-GC/MS进行分析。结果 从34批次样品中, 共鉴定出260种风味物质, 涵盖含硫化合物、醇类、醛类、酮类、酯类等多种类型。生、熟豆汁中含硫化合物相对含量较高, 而麻豆腐的风味物质种类多样、相似性较低。这些鉴定数据在一定程度上能够反映感官评价结果, 但存在部分风味物质较为突出或被其他气味干扰的可能性。此外, 本研究利用主成分分析(principal component analysis, PCA)法对样品整体分布及偏离样本进行鉴别并尝试分析偏离原因; 进一步利用正交偏最小二乘判别分析(orthogonal partial least squares discriminant analysis, OPLS-DA), 基于[P<0.05, 变量投影重要性(variable importance in the projection, VIP)>1]的筛选条件, 选出31种生、熟豆汁特征风味物质, 可用于生、熟豆汁的区分与鉴定。结论 研究证实PT-GC/MS结合多元统计方法可有效解析豆汁、麻豆腐风味物质, 筛选特征物质, 为后续优化改善产品风味提供依据。

英文摘要:

      Objective To identify flavor compounds in Douzhir and Ma Tofu and analyze their characteristic components based on purge and trap-gas chromatography/mass spectrometry (PT-GC/MS) combined with the national institute of standards and technology (NIST) database. Methods Weigh 2.0 g of sample into a 40 mL brown spiral sample bottle, add 10 mL of experimental water and a tetrafluoroethylene magnetic stirrer, heat the sample at 40 ℃, and analyze it by PT-GC/MS. Results A total of 260 kinds of flavor compounds were identified across 34 batches, including sulfur-containing compounds, alcohols, aldehydes, ketones, esters, etc. Raw and cooked Douzhir exhibited significantly higher relative abundances of sulfur-containing compounds compared to Ma Tofu, which showed greater diversity but lower similarity in flavor profiles. These identification data could to some extent reflect sensory evaluation results, but there was a possibility that some flavor compounds might be more prominent or interfered with by other odors. In addition, this study used principal component analysis (PCA) method to identify the overall distribution of samples and deviations from samples, and attempted to analyze the reasons for deviations. Further, using orthogonal partial least squares discriminant analysis (OPLS-DA), based on the screening conditions [P<0.05, variable importance in the projection (VIP)>1], 31 kinds of characteristic flavor compounds of raw and cooked Douzhir were selected, which could be used for the differentiation and identification of raw and cooked Douzhir. Conclusion The study confirms that PT-GC/MS combined with multivariate statistical method can effectively analyze the flavor compounds of Douzhir and Ma Tofu, screen the characteristic compounds, and provide a basis for the subsequent optimization and improvement of product flavor.