(a)
In general
The wine spirits authorized to be used in wine production shall be brandy or wine spirits produced in a distilled spirits plant (with or without the use of water to facilitate extraction and distillation) exclusively from—
(1)
fresh or dried fruit, or their residues,
(2)
the wine or wine residues, therefrom, or
(3)
special natural wine under such conditions as the Secretary may by regulations prescribe;
except that where, in the production of natural wine or special natural wine, sugar has been used, the wine or the residuum thereof may not be used if the unfermented sugars therein have been refermented. Such wine spirits shall not be reduced with water from distillation proof, nor be distilled, unless regulations otherwise provide, at less than 140 degrees of proof (except that commercial brandy aged in wood for a period of not less than 2 years, and barreled at not less than 100 degrees of proof, shall be deemed wine spirits for the purpose of this subsection).
(c)
Distillates containing aldehydes
When the Secretary deems such removal and use will not jeopardize the revenue nor unduly increase administrative supervision, distillates containing aldehydes may, under such regulations as the Secretary may prescribe, be removed without payment of tax from the bonded premises of a distilled spirits plant to an adjacent bonded wine cellar and used therein in fermentation of wine to be used as distilling material at the distilled spirits plant from which such unfinished distilled spirits were removed.