Today in 1973, US Patent 3729321 A was issued, an invention of N.L. Vacano, assigned to Rainier Companies, for their “Preparation Of Beer.” There’s no Abstract, but the description summarizes it. “This invention relates to the production of beer. More particularly, this invention is concerned with improvements in the process of producing beer starting with the wort, fermenting the wort with yeast to form green beer, aging of the beer and the subsequent finishing operation, as Well as improved apparatus for producing beer.”