Today in 1956, US Patent 2740049 A was issued, an invention of William C. Stein Sr., for his “Method and Apparatus for Destruction of Live Yeast Cells in Beer.” There’s no Abstract, but the description states that the “invention relates to a method and apparatus for destroying live yeast cells in beer.” When he lays out the various objects for the invention, it’s clear that the yeast is destroyed when “the beer is cascaded over violet ray tubes,” allowing for the “continuous treatment of the beer.” It apparently differs from how this was accomplished beforehand, as using this method “the beer will be subjected to a pre-carbonation pasteurization whereas under prior process the beer was pasteurized after carbonization.”