Today in 1979, US Patent 4138499 A was issued, an invention of Karl M. Strauss, Harold H. Geller, and Bernard J. Wagner, assigned to Pabst Brewing Co., for their “Preparation of Beer with Reduced Calories.” Here’s the Abstract:

A low dextrin and low carbohydrate beer having reduced calories is produced by fermenting wort with yeast in the absence of readily fermentable carbohydrates so that the yeast act on fermentable ingredients in the wort other than readily fermentable carbohydrates. After fermenting a major portion of fermentable ingredients, there is added to the resulting alcoholic wort a quantity of one or more readily fermentable sugars and fermentation is continued until the real degree of fermentation is at least 80%. By this process a low calorie beer can be prepared without the use of a carbohydrate splitting enzyme such as amyloglucosidase.