Today in 1977, US Patent 4053653 A was issued, an invention of Junjiro Miyata and Yasushi Kikuchi, assigned to Asahi Breweries, Ltd., for their “Method of Obtaining Lupulin-Rich Products from Hops.” Here’s the Abstract:

A method of obtaining lupulin-rich products from hops, which comprises: subjecting frozen hop cones to coarse crushing by a first crusher equipped with a screen having width of openings in the range of 6 – 15 mm and sieving fragments of crushed hops passing therethrough to obtain a first lot of lupulin-rich product as accumulated beneath the sieve; and then subjecting the portion which passed over the screen of the sieve to recrushing by a second crusher equipped with a screen having narrower openings than that of the first crusher a screen having width of openings in the range of 3 – 6 mm, and sieving fragments of recrushed hops passing therethrough to obtain a second lot of lupulin-rich product as accumulated beneath the sieves.
The method is performed on hops and particles thereof maintained in the frozen condition.