Bourbon has no minimum specified duration for its aging period. Products aged for as little as three months are sold as bourbon. 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 be – but is not required to be – called straight bourbon.
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