Question: I have noticed that certain Scotch whiskies now have a hechsher on them. Does whisky need a hechsher?
Answer: The poskim agree that ordinary Scotch whisky (whether single malt or blended) which has no mention of any wine casks is perfectly Kosher. The question arises when whisky has been matured in wine casks, such as the Macallan Sherry Oak. R’ Moshe Feinstein famously addresses this issue in 2 responsa: Igros Moshe YD 1:62-63. While the Shulchan Aruch (YD 134:13) forbids drinking a gentile’s beverage when it is customary to add non-Kosher wine to it, R’ Moshe follows the more lenient Rema. Providing the wine is nullified against 6 parts whisky (as opposed to the usual 1:60 ratio), the wine is Kosher. While R’ Moshe advises that a baal nefesh should best avoid such whisky, seemingly he was specifically referring to a scenario where wine had actually been added to whisky. As Scotch Whisky Regulations dictate that Scotch may only contain water, grain yeast and caramel colouring, we can be assured that wine is not added.
Many American poskim are concerned that as the entire sherry (or port,
etc.) cask is saturated with non-Kosher wine, the wine is no longer battul 1:6
in the whisky. Others, including R’ Akiva Niehaus (Sherry Casks, A Halachic
Perspective) argue that R’ Moshe wasn't referring to Scotch, but to American or
Canadian whiskey. Accordingly, they forbid Wine Cask Finishes, arguing
that the wine adds a recognizable taste to the whisky.
Nonetheless, Rabbanim in theNote, that distilleries outside of
UK (including the London Beis Din) maintain that R’
Moshe’s rulings apply to Scotch, and follow R' Yitzchok Yaakov Weiss’s permissive ruling,
too (Minchas Yitzchak ).