The Secret Ingredient in Avery Brewing Company’s Latest Brew? Human Saliva.

Avery Brewing Company’s Pachamama varietal, on tap solely at its Boulder facility, is unlike any beer I’ve ever tasted. It’s a light, slightly carbonated, floral brew that carries many of the delightful notes of a complex sour—fruity and herbacious elements play with the faintest hint of bitterness—but it doesn’t taste sour in the least. And, also unlike any other beer I’ve ever sipped, it’s made with human saliva.

Travis Rupp, Avery’s research and development manager and a University of Colorado Boulder professor of archaeology and ancient history, was inspired to create Pachamama by an ancient Peruvian technique for making “chicha.” The Old World alcoholic drink began with a base of corn, quinoa, and beans which were chewed, spit out, and then allowed to ferment into a fruity, starchy brew.

Turns out, there’s an enzyme in human saliva that helps break down the sugars in grains and seeds, contributing to the fermentation process. So, Rupp spit into Avery’s corn and quinoa mash before fermenting the brew with wild yeasts. If that sounds off-putting, don’t worry: The boiling part of the process kills any germs that may have lingered.

The result of Rupp’s effort is a splendidly sippable 5.2 percent ABV beer, ideal for the hop-averse or craft beer rookies (just don’t tell them about the secret ingredient). Rupp brewed just one batch, so hurry to the tap room to get it while you still can—it’ll likely be around for the next month or so. 4910 Nautilus Court, Boulder, 303-440-4324