27 CFR 5.26 - Formula requirements.
(a) General. An approved formula is required to blend, mix, purify, refine, compound, or treat spirits in a manner which results in a change of character, composition, class or type of the spirits. Form 5110.38 (27-B Supplemental) shall be filed in accordance with the instructions on the form and shall designate all ingredients and, if required, the process used. Any approved formula on Form 27-B Supplemental or Form 5110.38 shall remain in effect until revoked, superseded, or voluntarily surrendered. Any existing qualifying statements as to the rate of tax or the limited use of drawback flavors appearing on a Form 27-B Supplemental are obsolete.
(b) Change in formula. Any change in an approved formula shall require the filing of a new Form 5110.38. After a change in a formula is approved, the original formula shall be surrendered to the appropriate TTB officer.