For purposes of this chapter (except when used with reference to distilling or distilling material) the term beer means beer, ale, porter, stout, and other similar fermented beverages (including sake or similar products) of any name or description containing one-half of 1 percent or more of alcohol by volume, brewed or produced from malt, wholly or in part, or from any substitute therefor.
For purposes of this subpart, the term gallon means the liquid measure containing 231 cubic inches.
For purposes of this chapter, the term “brewer” means any person who brews beer or produces beer for sale. Such term shall not include any person who produces only beer exempt from tax under section 5053(e).