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Bourbon has no minimum specified duration for its aging period.
[23] Products aged for as little as three months are sold as bourbon.
[24] The exception is
straight bourbon, which has a minimum aging requirement of two years. In addition, any bourbon aged less than four years must include an age statement on its label.
Bourbon that meets the above requirements, has been aged for a minimum of two years, and does not have added coloring, flavoring, or other spirits
may (but is not required to) be called
straight bourbon.
[27]
- Bourbon that is labeled as straight that has been aged under four years must be labeled with the duration of its aging.[28]
- Bourbon that has an age stated on its label must be labeled with the age of the youngest whiskey in the bottle (not counting the age of any added neutral grain spirits in a bourbon that is labeled as blended, as neutral-grain spirits are not considered whiskey under the regulations and are not required to be aged at all).[25]
Bourbon that is labeled
blended (or as
a blend) may contain added coloring, flavoring, and other spirits (such as un-aged neutral grain spirits); but at least 51% of the product must be
straight bourbon.
[29][30]
Bourbon which has been aged for fewer than 3 years cannot legally be referred to as whiskey (or whisky) in the EU.
[31]