27 C.F.R. § 19.22 Attachment of tax.
Title 27 - Alcohol, Tobacco Products and Firearms
Under 26 U.S.C. 5001(b), the tax attaches to spirits as soon as the substance comes into existence as such, whether it be subsequently separated as pure or impure spirits, or be immediately, or at any subsequent time, transferred into any other substance, either in the process of original production, or by any subsequent process. (Sec. 201, Pub. L. 85–859, 72 Stat. 1314, as amended (26 U.S.C. 5001))
Title 27: Alcohol, Tobacco and Firearms
PART 19—DISTILLED SPIRITS PLANTS
Subpart C—Taxes
Gallonage Taxes
§ 19.22 Attachment of tax.

