Today in 1915, US Patent 1161272 A was issued, an invention of Henning Wennersten, for his “Method of Preserving Hops.” There’s no Abstract, although in the description it includes this summary:

My invention is particularly designed to preserve the fresh or prime hops, or similar flowers or substances, in their best condition, so to prevent the escape of the valuable volatile elements, such as lupulin, and the deterioration of the hops by reason of the air coming more or less in contact therewith. It is also designed to produce a new product, which will add greatly to the convenience of handling and shipping the hops, which will also preserve them an indefinite length of time in any climate, and which in its nature may readily be employed in the manufacture of beer and other products where hops are essential, insuring accuracy in the use of the valuable chemical elements, or the ingredients employed, and dependability upon the grade or quality of such ingredients.