It has been a long time since the MacVey family took Abu Musa Jabir ibn Hayyan secrets of distillation and converted them into the first bottles of whisky, some 1200 years ago. Originally used as an internal anesthetic and an external antibiotic, whisky (from the Gaelic uisge, meaning “water of life”) has become the most popular liquor in the world.
But such popularity could not be free of controversy. Ireland and Scotland both claim to have given birth to whiskey (food expert Kate Hopkins calls it a teiku and leaves the matter unresolved since no country can bring definitive proof). The “Whisky Ring”, a bribing scheme involving hundreds of whisky distillers and government officials, was among the muddiest chapters in 19th century American politics. There is even a machloket concerning the proper spelling of the word: The Scots spell it “whisky” and the Irish spell it “whiskey”. For us, Torah Jews, the controversy has a different name: Sherry Casks.
The process of making whisky is quite straightforward: The grains are crushed, water is added, the mixture is boiled and yeast is added for fermentation (by now, we basically have beer). Then it is distilled and aged in wooden barrels. Although easier said than done, at least it poses no real halachic problems, except for the last stage, the aging in the barrels.
In his extraordinary booklet, Rabbi Akiva Niehaus suggests that whisky was originally aged in any type of barrel, preferably a used one, so the sharp tannins found in the wood would not ruin the delicate flavor of Scotch. Sherry wine casks were abundantly available simply because Spanish producers would send their wine in barrels to England to be bottled. This continued until the 1970s when sherry producers began bottling their wine and casks were no longer found in abundance in the UK. So whisky producers bought American bourbon casks instead. But consumers were not happy. Something in their drink did not taste the same. Now they had to go out of their ways to get those old sherry casks, going as far as filling new barrels with sherry just to mature the whisky later on.
This, of course, presents a complex halachic question, as we shall explore. The Gemara in Avoda Zara explains that any wine owned or produced by non-Jews may not be consumed by rabbinic law because it may lead to intermarriage and, eventually, idolatry. Some sources identify this decree dating back to the time of the Jewish people in the desert when Pinchas, following the shameful affair with the daughters of Midian, forbade any consumption of non-Jewish wine. Sherry wine, a pungent variety from the Spanish region of Jerez is certainly considered stam yeinam and is therefore forbidden by halacha. What is the status of other drinks mixed with it? Must they be annulled? If so, at what ratio?
The Gemara relates an incident where Ravina allowed his son, Rav Chiya, to store beer in a barrel previously used for non-kosher wine. Accordingly, the Shulchan Aruch codifies that vessels prohibited by non-Jewish wine may be used for storing water, beer and other liquids in them, as long as they were rinsed beforehand. The reason, explains the Taz, is because the flavor of wine ruins the other liquids (notein ta’am lifgam). Therefore, even if the liquids were stored for more than twenty-four hours in the barrel (the time needed for a liquid to absorb the flavors contained in the walls of a utensil), they may still be consumed. If so, why is there even a question? Is not whiskey among the “other liquids” permitted by the Shulchan Aruch?
Clearly not. Whiskey distillers make a big fuss about the sherry cask aging. They even take on extra expenses to do so and consumers are willing to pay the added price for the enhanced flavor. Connoisseurs seem to agree that sherry whisky is superior to regularly aged whisky, although there is little consensus on how this is achieved: it is clearly not just the wine. Otherwise, wouldn’t it be easier and cheaper to just add a small proportion of wine into the whisky?
In any event, halachic authorities understand that we cannot rely on the notein ta’am lifgam leniency when the mixture is enhanced. This idea is expressed clearly by the Magen Avraham on the laws of Pesach.
Similarly, we cannot rely on the fact that wine absorbed in the casks is most certainly not ben yomo when the whiskey is poured since, as the Rema explains, wine does not become pagum even after 24 hours. In fact, says the Shach, instead of getting ruined, the flavor of wine actually improves with time.
Therefore, the question is, can the good taste of the wine imparted into the whisky even be nullified? After all, there is a rabbinic prohibition to annul forbidden mixtures lechatchila (a priori). The Shulchan Aruch states that if a person does so b’meizid (knowingly), the food becomes forbidden to him and to the person for which the nullification was intended. Even more so, Rabbi Akiva Eiger quotes opinions that hold that even when a seller nullifies the forbidden taste for unknown customers, it is prohibited to them. However, poskim were lenient when the nullification was made for a majority of non-Jewish consumers, as is the case of any whisky distillery.
If so, what is the amount of wine that must be annulled, and at what ratio? There is a dispute among the poskim on how much wine is absorbed into the cask. In Siman 135, the Shulchan Aruch states that a vessel filled with forbidden wine absorbs only kedei klipa (a thin layer) and therefore may be kashered by peeling that layer. The Taz assumes that this is the halacha even if the wine was in the vessel for a long period of time. However, the Shach is of the opinion that kevisha (soaking a liquid in a vessel for twenty-four hours) is just like cooking and, therefore, gives of its taste to the whole vessel. Since it is impossible to know how much taste is actually absorbed, the halacha assumes the worst case scenario, meaning that the entire vessel is filled with taste. There does not seem to be clear cut agreement on who to follow, and some later poskim side with the Taz (klipa), while others hold like the Shach (the whole vessel).
Regarding the ratio required to annul the absorbed wine, the Tur quotes a dispute among the Rishonim. Some of them assume that it is like any other foho rbidden taste, which requires sixty times the volume of permitted food to become nullified, while a second opinion suggests it may be annulled in just six times its volume. The source of the lenient opinion is the understanding of the Ra’avad and the Ri of Rabbi Yochanan’s ruling in the Gemara Avoda Zara that if one had two cups of wine, one non-sacred and one of teruma, and he diluted them with water and mixed them together, one should consider the permitted non-sacred wine as “nonexistent” and the teruma wine is then nullified by the water. Since the Gemara does not specify the size of the cups nor the amount of water added, the Ra’avad and the Ri assume they are two equally sized cups, diluted by three parts of water each, as was the practice in Talmudic times. Given the halacha of considering the permitted non-sacred wine as “nonexistent” in matters of nullification, it can be inferred that there is one part of wine against six of water. The Shulchan Aruch follows this lenient opinion.
Why is wine different from any other beverage that should be annulled in just six parts as opposed to sixty? The Rashba explains that when mixed with six parts of water, it can no longer be considered wine. Rather, it becomes some acid beverage called kihua, which imparts a ruined flavor.
It is not clear though whether this ratio of nullifying wine in a mixture of 1:6 is something particular to wine mixed with water according to these opinions or would apply as well to wine mixed with other liquids. Once again, this is a matter of dispute between the Taz and the Shach. In Siman 114, The Rema prohibits buying beverages from non-Jews when it may be assumed that wine was mixed into them in a ratio of more than one in sixty. The Shach consequently infers that wine can only be nullified in water in a ratio of 1:6, but in other liquids, a ratio of 1:60 is needed. The Taz, however, believes that the Rema is simply quoting the source of this ruling (the Mordechai in the name of the Ra’avia), but the Rema himself requires only a ratio of 1:6 to annul the wine, regardless of the beverage. Later poskim seem to agree with the Taz and suggest that the wine in the casks, even if it does impart taste, is considered kihua. This seems to be an integral part of the argument of Rav Moshe Feinstein and Rav Yitzchak Weiss to permit whisky. Accordingly, we can assume that the flavor of the wine can be annulled in the casks if we can ascertain that there is a six to one ratio present.
Another potential issue concerning sherry casks is the ruling of the Shulchan Aruch that imposes a limit to nullifications on ingredients specifically intended to give flavor (avida l’taama), as long as their taste is perceived. This issue, however, can be deflected either by arguing that once it becomes kihua it no longer enhances the taste or by saying that even whisky producers are not really interested in the flavor of wine (even when the labels clearly say they do). Rav Weiss suggests that the main purpose of adding the wine is reducing the negative impact of the wood on the liquor. Here too, it seems obvious that even when the sherry affects the whisky, it does so in an indirect manner, which could not be accomplished by just adding wine.
Consequently, our main question remains: Are there six parts of whiskey against the amount of absorbed wine? Rabbi Niehaus estimates a ratio of 3.76 to 1, if we consider the whole volume of a standard wooden sherry cask. Although he does not address this point, it is obvious there is much more than six to one if we were to follow the opinion mentioned above of the Taz that considers only a klipa of the cask as being absorbed with wine.
Besides the issues mentioned here, many other issues that are beyond the scope of this article must also be considered in determining the halachic status of whisky in sherry casks: How many times was the cask filled with whisky? What about casks that mix sherry and bourbon? What is the halacha for blended whiskys that were only partly matured in sherry casks? When can a person rely on the information given by the distillery or printed on the bottle? The safest thing to do in these types of cases is to acquire only supervised products, unless a recognized halachic authority permits otherwise.
 “Whiskey: The Definitive World Guide”. Michael Jackson, DK; American ed. edition, 2005.
 Whisky annual sales are worth approximately 17.5 billion USD worldwide. Vodka, next on the list, sells for only 10.75 billion USD, according to www.vinepair.com
 “A guide to the lingo and history of whiskey”. Suemedha Sood, www.bbc.com
 The booklet is available online as well at http://www.crcweb.org/Sherry%20Casks%202.pdf
 “Sherry casks: A Halachic Perspective”; Rabbi Akiva Niehaus, Chicago Community Kollel, 2012.
 Avoda Zara 36b. As opposed to Torah prohibited wine which was used for idolatry (yayin nesech), rabbinically forbidden wine is called stam yeinam.
 Pirkei D’Rabbi Eliezer, Chapter 46. For further iyun, see “The Laws of Yayin Nesech and Stam Yeinam”, in Tzurba M’Rabanan, Vol. 5.
 Avoda Zara 33b.
 Shulchan Aruch, Yoreh De’ah 137:4
 Taz, Yoreh De’ah 137:7
 Magen Avraham, Orach Chaim 451
 Our Sages assume that usually, any absorbed taste in a vessel will only enhance the flavor of the food cooked in it for 24 hours, that is, as long as it is ben yomo. After that, any given taste is considered pagum, ruined, and no longer prohibits the food.
 Rema, Yoreh De’ah 137:1
 Shach, Yoreh De’ah 137:10
 Shulchan Aruch, Yoreh De’ah 99:5
 Rabbi Akiva Eiger, Yoreh De’ah 99:5
 See Responsa Igrot Moshe, Yoreh De’ah 1:62
 Shulchan Aruch, Yoreh De’ah 135:13
 Taz, Yoreh De’ah 105:1
 Shach, Yoreh De’ah 98:13
 Shulchan Aruch, Yoreh De’ah 98:4
 See, for example, Chochmat Adam 81:11 who follows the Shach, and the Chacham Tzvi 75 who follows the Taz.
 Tur, Yoreh De’ah 134
 Avoda Zara 73b
 Shulchan Aruch, Yoreh De’ah 134:5
 Rashba, Avoda Zara 73a
 Rema, Yoreh De’ah 114:4
 Nekudot HaKesef 114:4
 Igrot Moshe, Yoreh De’ah 1:62 and Minchat Ytzchak 2:28:4. It must be noted that Rav Moshe is dealing with a slightly different situation where wine was added to liquor but in small amounts. Nevertheless, many of the arguments apply to our case as well.
 Shulchan Aruch, Yoreh De’ah 98:8
 Minchat Ytzchak, Vol. 2 28:21
 Niehaus, Op. Cit.