Rev. Rul. 57-430

Iso-ascorbic acid may be used in the treatment of wines on bonded wine cellar premises, subject to the same restrictions and provisions of the regulations as are applicable to the use of ascorbic acid, the limited use of which was authorized in Revenue Ruling 57-175, C.B. 1957-1, 608. Accordingly, Revenue Ruling 57-175, supra , is hereby made applicable to iso-ascorbic acid as well as ascorbic acid.

Granular cork may be approved by Assistant Regional Commissioners, Alcohol and Tobacco Tax, pursuant to the provisions of section 240.530 of the Wine Regulations, for use in the treatment of wines stored in redwood and concrete tanks, in amounts not exceeding ten pounds per one thousand gallons of wine, since use thereof within the amount prescribed is considered as being consistent with good commercial practice.

Revenue Ruling 55-603, C.B. 1955-2, 709, containing a list of materials authorized for use in the treatment of wine, is hereby supplemented to include the above materials.