Unchained Series 23: Dark Infusión – A Coffee Milk Stout
Summit Brewing Company’s newest limited edition release is the brewery’s first-ever coffee beer, Unchained Series 23: Dark Infusión – A Coffee Milk Stout. In this blog, brewer Pete Stacy shares the story and inspiration behind his inaugural beer in the Unchained Series.
I LOVE coffee. It is my second favorite thing to drink…behind beer, of course. My favorite saying about coffee is “It takes a lot of coffee to make good beer”, referring to its abilities to fuel sleepy brewers with caffeine during the late night/early mornings! 
The first coffee beer that I fell in love with was the Mocha Java Stout from Barrio Brewing Co. in Tucson Arizona where I began my career as a brewer. I remember how amazing it smelled in the brewery when we made the coffee for the beer and added it to the brews. Since then I have been learning about the different ways that brewers incorporate coffee as an ingredient in the brewing process.
I first started by working with folks at Cafe Imports who specialize in sourcing and importing coffee from all over the world. I learned how coffee beans are selected and analyzed based on qualitative and quantitative analysis very much like how we brewers select and import our malts and hops. I selected specific beans grown in Colombia and Brazil, blended to fit the flavor and aroma profile I was looking for to complement the beer. I also learned about how cold brewing coffee helps retain a lot of the flavorful and aromatic organic compounds (and caffeine!) within the beans, and significantly reduces the development of acrid, astringent, and bitter flavors that are associated with hot brewed coffee.
After sourcing my beans and deciding to use a cold brewed coffee infusion, I partnered with Blackeye Roasting Co. We did several sensory trials with a few different blends of coffee mixed with a test batch of the milk stout to figure out the perfect ratio of coffee to infuse. It has been really cool getting to know those guys and learning more about their process and product, and I was able to participate in the roasting and brewing of the “Summit Blend” that we will use!
The Unchained Series is all about pushing boundaries and exploring new ideas & technologies, so this beer definitely fits that criteria! For this brew, we had the largest grain bill for a single batch that we have ever done, about 10,500 lbs of malt, which was a key factor for breaking the record for longest lauter process,…about 6 hours. Our brewhouse is not designed to brew such enormous batches, so it required a little creativity and teamwork to operate smoothly and do 4 batches consistently. We will also be rigging up a system to blend the coffee in-line with our centrifuge output during the filtration, which is another process that we have never done before at Summit.
This beer is especially for people who like coffee and dark beer. It will be a very good “dessert” beer that will be complemented well by some great coffee. Expect it to be heavy-bodied, sweet, smooth, and very roasty with strong coffee aromas. Trying this beer will also give people a chance to see the result of collaboration between two local companies that are pioneers in their respective industries.
Cheers!
Brewer Pete Stacy
