Today in 1978, US Patent 4123561 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 for brewing in which the hops and particularly the alpha acids in the hops are stabilized against deterioration, the process broadly comprising forming an intimate mixture of the hops or hop extracts with one or more oxides of a divalent metal or metals and maintaining the mixture under suitable conditions, preferably at an elevated temperature, e.g., 40°-100° C., until stabilization is substantially completed. In another aspect, the alpha acids present in the hops are converted to their isomerized products, which are desirable for brewing. The process is especially suitable for use in pelletizing operations.