Last year Sierra Nevada Brewing Company released a new year-round beer called Hop Hunter IPA. What makes this beer different from their other offerings—and pretty much every other IPA on the market—is the production method of the hops used in the brew.
In traditional beer making, hops are added toward the end of the brewing process. The bitterness of the hops balances the sweetness of the malts and adds aroma to the beer.
There are several ways hops can come, with dry, wet, and compressed pellets being the most common. However, there are new techniques being explored, and in the case of Hop Hunter, it is a concentrated form of hops produced by steam-distilling wet hops at the hop farm.
In this distillation process, hundreds of pounds of hops are exposed to steam that extracts the super-flavorful hop oil from the hop cones. Because the hop oil vaporizes at a lower temperature than water, the oil is first to boil off, and as the vapor condenses to form a liquid, the result is pure hop oil.
The goal for Hop Hunter is to preserve the fresh-off-the-vine wet-hops flavor for year-round brewing. For you geeks out there, Bravo hops are the bittering hops (added to the boil to balance the malts), the finishing hops (added at the end of the boil for aroma) are Cascade, Crystal, and Simcoe, and the oil is a distillation of Cascade, Centennial, and CMZ, added post-fermentation.
Another technique for extracting hop oil uses what is called “supercritical CO2.” In this process, hops are ground up to a ground coffee consistency and stuffed into a cylinder. Carbon dioxide is pumped in and compressed to high pressure, causing it to liquify. The liquid CO2 acts as a solvent that removes the oils from the hops. Then the pressure is lightened to a level where the CO2 returns to a gas and what is left is hop oil or crystals.
One notable beer that used CO2 extraction was in November 2015: Dogfish Head’s Hoo Lawd. Two labs scientifically confirmed it’s hoppiness at an astounding 658 IBUs.
The possibilities with hops extracts are still in their infancy, but be on the lookout for creative uses for them in future.