其他2017nature.com
威士忌稀释——分子视角
Dilution of whisky – the molecular perspective
专业 · 约 45 分钟读完前置知识：分子动力学模拟、溶液热力学、氢键与溶剂化
导读
这篇论文从分子层面研究威士忌加水稀释如何影响风味，重点考察与泥煤烟熏气味相关的愈创木酚（guaiacol）在乙醇-水混合体系中的分布和界面行为。结果显示，稀释比例会改变这些风味分子的溶剂环境，从而影响香气释放；因此加水到合适浓度可能增强风味，稀释过度则会让风味变淡。
HN 关注点：把“加几滴水更香”的饮酒经验放到分子层面解释，讨论还延伸到门捷列夫与伏特加40度标准、以及不同泥煤风味和酒精度的适用性。
HN 评论精选
这几条评论里：支持 1 质疑 3
质疑批评论文漏引门捷列夫关于乙醇/水溶液与伏特加40度标准的工作。
很失望，他们没有引用元素周期表之父关于乙醇/水溶液的开创性工作；这项工作常被用来解释为什么俄罗斯伏特加是 80 proof（约40%酒精度）。补充材料还提到，门捷列夫在1865年博士论文中提出，40%乙醇与60%水的溶液会形成特殊的分子簇（水合物），这后来成为全球伏特加标准。
georgecmu查看英文原文
It's disappointing they did not reference the seminal work by the father of the Periodic Table on ethanol/water solutions [1]. This work is often cited as justification for why Russian vodkas are 80 proof. 1. Mendeleev, D.I., O soedinenii spirta s vodoi, sochineniya (Total Collection of Transactions: On the Combinations of Alcohol with Water), Leningrad: ONTI-Khimteoret, 1937, vol. 4. UPDATE on Mendeleev's work with alcohols: https://www.acs.org/content/acs/en/pressroom/newsreleases/2010/june/brand-preference-may-be-in-the-drink-not-in-the-head.html Dale Schaefer and colleagues, who conducted the study, note that vodka has a long-standing reputation as a colorless, tasteless solution of 40 percent pure ethyl alcohol, or ethanol, and 60 percent pure water. All such beverages should have the same faint or undetectable taste. But sales of premium vodka brands have surged in recent years. Schaefer’s group at the University of Cincinnati worked with colleagues from Moscow State University in Russia to find an answer. They knew that famed Russian chemist Dmitri Mendeleev, noted for work on the Periodic Table of the Elements, made a key observation on alcohol solutions in his 1865 doctoral dissertation. Mendeleev believed that a solution of 40 percent ethanol and 60 percent water would develop peculiar clusters of molecules, called hydrates. That solution became the global standard for vodka, which usually is sold as an 80-proof, or 40 percent alcohol, beverage.
质疑质疑结论是否只适用于以愈创木酚为代表的泥煤味威士忌，并担心稀释损害其他风味物质。
这篇论文主要从愈创木酚（guaiacol）的角度看问题，而愈创木酚主要与泥煤味威士忌相关。这个结论对泥煤味不突出的威士忌也成立吗？加水稀释会不会对其他化合物造成负面影响？
levesque查看英文原文
This is mostly seen from the angle of guaiacol, which is relevant for peaty whiskies. Does this hold for less peat-forward whiskies? Could water dilution hurt some other compounds?
支持用一句话概括论文结论：稀释要适度，过犹不及。
要点/太长不看版：“总体而言，在把威士忌稀释到好喝与稀释到浪费之间，存在一个微妙的平衡。”
skydoctor查看英文原文
Takeaway/tl;dr: "Overall, there is a fine balance between diluting the whisky to taste and diluting the whisky to waste"
质疑指出爱好者市场常见40%以上甚至原桶强度威士忌，“装瓶前都稀释到40%”的说法不准确。
原文说威士忌蒸馏到约70% ABV，再稀释到约40%。这对绝大多数威士忌可能成立，但到了爱好者领域，威士忌的酒精度从40%到60%以上都有；其中一些（包括但不限于原桶强度装瓶）就是设计来让饮用者继续稀释的，或者说把稀释到合适口味的选择权交给顾客。原文说装瓶前稀释到约40%会显著改变味道、爱好者也会加几滴水来增强风味——至少在我熟悉的爱好者圈子里，这并不成立；40%的威士忌在这些圈子里正越来越少。
tehsuk查看英文原文
> Whisky is distilled to around 70% alcohol by volume (vol-%) then diluted to about 40 vol-% Might be true for the vast majority of whisky, but once you start to hit enthusiast territory, there's whisky from 40% to above 60% ABV. Some of those (including but not limited to "cask strength" bottlings) are certainly made for diluting further. Or rather, to give the customer the option to dilute to taste. > Before bottling, the whisky is diluted to around 40 vol-% by the addition of water, which changes the taste significantly. Whisky enthusiasts often also add a few drops of water to the spirit before drinking in order to further enhance the taste. I'd say that's simply not true, at least for my "enthusiast" circles. 40% whiskies are becoming increasingly rare in those groups.
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