Kumazawa Kenji, Masuda Hideki
Material Research and Development Laboratories, Ogawa and Company, Ltd., 15-7 Chidori Urayasushi, Chiba 279-0032, Japan.
J Agric Food Chem. 2003 Apr 23;51(9):2674-8. doi: 10.1021/jf021025f.
Heat processing is responsible for the change in the flavor of a coffee drink. In this study, the application of gas chromatography-olfactometry of headspace samples (GCO-H) using the vapor fraction before and after heat processing of the coffee samples resulted in the detection of 12 odor-active peaks for which the flavor dilution (FD) factors changed. Eight potent odorants were identified from these peaks by gas chromatography-mass spectrometry (GC-MS). Among these components, methanethiol (putrid), acetic acid (sour), 3-methylbutanoic acid (sour), 2-furfuryl methyl disulfide (meaty), and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (caramel-like) increased after heating of the coffee sample, whereas 2-furfurylthiol (roasty), methional (potato-like), and 3-mercapto-3-methylbutyl formate (roasty) decreased compared with the coffee sample before heat treatment. In addition, extensive studies have been carried out on the pH effects on the change in the concentration of 2-furfurylthiol during heat processing and in the pH range of 5-7; it was found that the concentration of this compound in the model solutions had significantly changed.
热处理会导致咖啡饮品风味的变化。在本研究中，对咖啡样品进行热处理前后，利用顶空样品的气相色谱 - 嗅觉测定法（GCO - H），通过蒸汽馏分检测到12个气味活性峰，其风味稀释（FD）因子发生了变化。通过气相色谱 - 质谱联用（GC - MS）从这些峰中鉴定出8种强效气味物质。在这些成分中，咖啡样品加热后甲硫醇（腐臭味）、乙酸（酸味）、3 - 甲基丁酸（酸味）、2 - 糠基甲基二硫化物（肉香味）和4 - 羟基 - 2,5 - 二甲基 - 3(2H)-呋喃酮（焦糖味）增加，而与热处理前的咖啡样品相比，2 - 糠基硫醇（烤香味）、甲硫基丙醛（土豆味）和甲酸3 - 巯基 - 3 - 甲基丁酯（烤香味）减少。此外，还对热处理过程中以及pH值在5 - 7范围内2 - 糠基硫醇浓度变化的pH效应进行了广泛研究；结果发现该化合物在模型溶液中的浓度有显著变化。
