Although drip coffee and espresso has predominantly been at the forefront of the third wave coffee movement, iced coffee has begun to garner its own cultish following. While previously you could find the coffee snobs bickering over the superiority of the Japanese versus Toddy brewing methods, as well as cold brew being on tap, soon people will hear the order “nitro cold brew” so much, that they might be confused whether they’re in a coffee shop or a freshman year chemistry lab.
This past month, I happened to come across nitro cold brew at the Culture and Stumptown coffee shops in New York’s Flatiron District. According to Diane Aylsworth of Stumptown Coffee Roasters, the Portland-based coffee company has always tried to stay ahead in the black gold market, especially with respect to iced coffee, and Stumptown is a result of just that. Given the rise in the popularity of cold brew, Stumptown began focusing on producing fresh and flavorful iced coffee in large batches to match the demand, and according to Aylsworth, this led to the creation of nitro cold brew. “In 2012, Stumptown brought in a food scientist who happened to be in the DIY beer brewing scene,” Aylsworth says. “He thought that we could apply draft beer science to coffee, where we would store the coffee in kegs with nitrogen and thus make it possible to transport large quantities of iced coffee while maintaining its freshness.”
After seeing the process occur in front of me, it was kind of dumbfounding to discover how simple the actual science was. Aylsworth explains that the nitrogen is infused into the keg with the coffee in a process akin to that of draft beer and is pushed through the tap with tremendous PSI via a five-holed disc. “That’s how the coffee gets the cascading effect with a foamy head and big, creamy mouthfeel,” she explains.
At Culture, I watched the barista pull from the tap what looked like a Guinness Stout, leaving me slightly perplexed when I placed my order for coffee. However, after having tried the caffeinated Guinness-reminiscent brew, it made going back to the archaic toddy method all too difficult. When comparing the two different brewing processes, Toddy brewing causes the end product to be more acidic more bitter flavor wise, with a thin and blase mouthfeel that often entails the coffee geeks worst nightmare of adding of milk. With nitro, however, the acidity is diminished and the mouthfeel is big and creamy, with some non-black coffee drinkers in pure shock that milk wasn’t added. The most important perk that justifies the extra 50 cent charge is, as Aylsworth emphasizes, “the bigger and more complex aroma, as well as the nitrogen bubbles in the coffee that cause the beverage to be better dispersed across to palette and allow the drinker to better appreciate the flavor.”
Although Stumptown’s nitro cold brew was an original creation that it released in 2013 for its own shops, other coffee shops began to carry nitro on tap at the same time. “The coffee shop world is pretty fragmented, so it’s not uncommon to see people with the same ideas, even without any communication before the launch,” Aylsworth says. Post-nitro, however, Stumptown is focusing more on their cold Ready-To-Drink (RTD) coffees. “We’ve already got the Stubbies and these coffee-and-milk cartons that are releasing soon in Whole Foods,” Aylsworth says. “Maybe we’ll eventually move nitro to the RTD format.” Whatever unorthodox convention Stumptown brews up next, expect to see those chemistry lab experiments you skipped out on shaping the nature of your favorite morning beverage.