水牛乳双皮奶制备过程中风味物质变化分析

Analysis of the Changes in Flavor Substances during the Preparation of Double-layer Steamed Milk Custard from Buffalo Milk

摘要:

为了解双皮奶（Double-Layer Steamed Milk Custard, DLSMC）制备过程中挥发性化合物变化，利用电子鼻和顶空-气相色谱-离子迁移谱（Headspace-Gas Chromatography-Ion Mobility Spectrometry, HS-GC-IMS）解析四个关键阶段（原料阶段-A组、煮沸阶段-B组、摊皮阶段-C组、炖奶阶段-D组）的挥发性物质。结果表明，甲基类与醇、酮、醛类化合物是不同阶段之间极显著差异的挥发性成分（P<0.01）。HS-GC-IMS共鉴定出38种化合物，包括酯类、醇类、酮类、醛类、醚类、酸类和吡嗪类衍生物。主成分分析（Principal Component Analysis, PCA）和偏最小二乘判别分析（Partial Least Squares Discriminant Analysis, PLS-DA）反映煮沸阶段和炖奶阶段是挥发性化合物变化的主要阶段。煮沸阶段（B组）可显著减缓原料乳中1-戊醇的不良风味（P<0.05），同时提高2-丁酮、2-丁醇、二甲基硫醚等化合物含量（P<0.05）。炖奶阶段（D组）中2-戊酮、2-庚酮、丙酮和二烯丙基二硫醚的显著增加（P<0.05）。双皮奶最终形成草香味、油脂味、果香味、奶香味、甜香味、黄油味、水果味、烤坚果味的风味特征。该研究揭示双皮奶制备过程中挥发性化合物的含量变化规律，为解析其风味特征的形成提供理论基础。

Abstract:

The changes in volatile compounds during the preparation of double-layer steamed milk custard (DLSMC) were investigated in this study. Volatile substances at four key stages of the preparation process, namely the raw material stage (group A), boiling stage (group B), skin separation stage (group C), and steaming stage (group D), were analyzed using an electronic nose and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). The analysis identified methyl compounds, alcohols, ketones, and aldehydes as volatile components with highly significant differences across the stages (P<0.01). Meanwhile, HS-GC-IMS identified 38 compounds, including esters, alcohols, ketones, aldehydes, ethers, acids, and pyrazine derivatives. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) indicated that the changes in volatile compounds were primarily attributed to the boiling and steaming stages. During the boiling stage (B group), the unpleasant flavor of 1-pentanol in raw buffalo milk was significantly ameliorated (P<0.05), while the levels of 2-butanone, 2-butanol, and dimethyl sulfide were significantly increased (P<0.05). In the steaming stage (group D), the levels of 2-pentanone, 2-heptanone, acetone, and diallyl disulfide were significantly increased (P<0.05). Ultimately, flavor characteristics, such as grassy, oily, fruity, milky, sweet, buttery, fruity, and roasted-nut aromas, were formed in the DLSMC. The present study revealed changes in volatile compounds during the DLSMC preparation process and provided a theoretical basis for elucidating the mechanisms underlying its flavor characteristics.