Today in 1979, US Patent 4154865 A was issued, an invention of Herbert L. Grant, assigned to S. S. Steiner, Inc., for his “Method for Processing Hops for Brewing.” Here’s the Abstract:
There is provided a method of processing hops or hop extracts for brewing in which hops and particularly the alpha acids in the hops are stabilized against deterioration and light sensitivity, the process broadly comprising isomerizing a substantial portion of the alpha acids in the hops and contacting said iso-alpha acids witha metallic hydride compound, the metal thereof being suitable for use in foods, until the reaction is substantially completed. In another aspect, the alpha acids present in the hops are converted to their reduced isomerized products which are desirable for brewing. The process is especially suitable for use in pelletizing operations.