Samuel Adams Kosmic Sour

image sourced from Boston Beer Company

Released Late August

Samuel Adams Kosmic Sour is a tart and wild ale that’s light-bodied and crisp with subtle cereal notes. It’s a dark golden beer that offers complex flavors including strong red fruit notes upfront, balanced by sour and sweet pale malts. 

Kosmic Sour is blended with a funky Belgian beer called Kosmic Mother Funk (KMF)®, an ale with spontaneous fermentation that’s been aged for two years in Hungarian oak barrels called foeders. Wild yeasts in these barrels impart a unique, fruity, funky character on the beer for a slightly tart and mostly dry finish. 

Through the extensive research and development of Kosmic Sour, multiple variations of this beer have been featured in our Boston Brewery Tap Room where it consistently ranks in the top five of weekly sales. Based on this success and the growth of the style, we’re thrilled to expand the offering nationwide for the first time ever with this seasonal limited release. 

Pairing with Food: Kosmic Sour complements both sweet and savory flavors with its complex fruity and tart character. Pair it with marinated meats such as chicken or flank steak, or even a bitter arugula salad topped with grilled chicken, where the funky notes of Kosmic Sour will add a layer of depth to the dish. For a twist, try Kosmic Sour with a salted caramel chocolate torte. 

Samuel Adams Kosmic Sour Style Profile Style Ale blended with Kosmic Mother Funk Malt Varieties Samuel Adams two-row pale malt blend, white wheat, Special B, Munich 10 Hop Varieties Centennial IBUs 11 Color Dark Golden / 8 SRM Alcohol 4.6% ABV Yeast Samuel Adams ale yeast, Brettanomyces First Brewed 2018

4.6% ABV | 11 IBU

About Boston Beer Company

The Boston Beer Company began in 1984 with a generations-old family recipe that Founder and Brewer Jim Koch uncovered in his father’s attic and brought to life in his kitchen. That beer was aptly named Samuel Adams Boston Lager, in recognition of one of our nation's great founding fathers, a man of independent mind and spirit. Little did Jim know at the time, Samuel Adams Boston Lager would soon become a catalyst of the American craft beer revolution.

Today, at Boston Beer, we brew more than 60 styles of Samuel Adams beer. We relentlessly pursue the development of new styles and the perfection of classic beers by searching the world for the finest ingredients. We remain focused on brewing quality beer and challenging drinkers’ perceptions of what beer can be through the use of innovative ingredients and brewing techniques. We are committed to elevating the image of American craft beer and are one of the world’s most award-winning breweries at international beer competitions. Although Samuel Adams beer is one of America's largest-selling craft beer, it accounts for only about one percent of the U.S. beer market.

The Boston Beer Company will continue its independently-minded quest to brew great beer and to advocate for the growth of craft beer across America. In addition to Samuel Adams beers and the other craft beers brewed by A&S Brewing, our craft beer incubator, our family of brands include Twisted Tea and Angry Orchard hard cider. For more information, please visit, and