Kreitman Gal Y, Danilewicz John C, Jeffery David W, Elias Ryan J
Department of Food Science, College of Agricultural Sciences, The Pennsylvania State University , University Park, Pennsylvania 16802, United States.
44 Sandwich Road, Ash, Canterbury, Kent CT3 2AF, United Kingdom.
J Agric Food Chem. 2017 Mar 29;65(12):2564-2571. doi: 10.1021/acs.jafc.6b05418. Epub 2017 Mar 15.
Fermentation-derived volatile sulfur compounds (VSCs) are undesirable in wine and are often remediated in a process known as copper fining. In the present study, the addition of Cu(II) to model and real wine systems containing hydrogen sulfide (HS) and thiols provided evidence for the generation of disulfides (disulfanes) and organic polysulfanes. Cu(II) fining of a white wine spiked with glutathione, HS, and methanethiol (MeSH) resulted in the generation of MeSH-glutathione disulfide and trisulfane. In the present study, the mechanisms underlying the interaction of HS and thiols with Cu(II) is discussed, and a prospective diagnostic test for releasing volatile sulfur compounds from their nonvolatile forms in wine is investigated. This test utilized a combination of reducing agents, metal chelators, and low-oxygen conditions to promote the release of HS and MeSH, at levels above their reported sensory thresholds, from red and white wines that were otherwise free of sulfidic off-odors at the time of addition.
发酵产生的挥发性硫化合物（VSCs）在葡萄酒中是不受欢迎的，通常在一个称为铜澄清的过程中进行修复。在本研究中，向含有硫化氢（HS）和硫醇的模型和真实葡萄酒体系中添加Cu（II），为二硫化物（二硫烷）和有机多硫烷的生成提供了证据。用谷胱甘肽、HS和甲硫醇（MeSH）加标的白葡萄酒进行Cu（II）澄清，产生了MeSH-谷胱甘肽二硫化物和三硫烷。在本研究中，讨论了HS和硫醇与Cu（II）相互作用的潜在机制，并研究了一种从葡萄酒中以非挥发性形式释放挥发性硫化合物的前瞻性诊断测试。该测试利用还原剂、金属螯合剂和低氧条件的组合，以促进HS和MeSH从添加时无硫化异味的红葡萄酒和白葡萄酒中释放，释放水平高于其报告的感官阈值。
