Today in 1930, US Patent 1767646 A was issued, an invention of George S. Bratton, assigned to Anheuser-Busch, for his “Process For Manufacturing Yeast.” There’s no Abstract, although in the description it includes this summary:

This invention relates to the manufacture of yeast, and particularly, to processes of the kind which contemplate initiating propagation of yeast in a dilute Wort, and thereafter adding or feeding into same a highly concentrated Wort .that contains yeast nourishing materials.