The Cumulus Machine Review: Fast and frothy cold brew

But a word about oxygen. The device essentially pumps pure air (79 percent nitrogen, 20 percent oxygen) into the coffee instead of using nitro cartridges. That’s cool, but oxygen exposure is the known enemy of fresh-tasting coffee. After the nitro evaporated, parallel taste tests actually showed more flabby oxidation flavors in the nitro than in the basic non-nitro.

But you can’t see much of it fresh out of the machine. What you notice are invigorating, fun bubbles that also add a perceived sweetness. These bubbles cover up many sins and form a dense head of foam on the cold brew that looks for all the world like a well-poured Irish stout.

A WIRED editor, looking at a photo of Cumulus’ abundant nitro, gleefully suspected chicanery. “I would swear they used Guinness for the promo shots,” he wrote.

The espresso is also fizzy – with a thick and real crema created by the pressure of the machine’s powerful compressor. It was the natural frothiness of the Cumulus espresso that resulted in my deliciously frothy martini – a result that had eluded me with chilled, hot espresso.

Strong tip to Virginia cocktail consultant and educator Josh Seaburg Model citizen cocktailsfor a good espresso martini recipe to try. As a reminder, this included 1.5 ounces of vodka, .75 ounces of coffee liqueur like Mr. Black, and half an ounce of simple syrup mixed with an ounce of cold espresso. Mix, shake, pour. The device only makes double shots, so one capsule provides enough cold espresso for two cocktails.

Who is Cumulus suitable for?

On the one hand, the Cumulus is an impressive piece of engineering – one that succeeds on multiple fronts where other device makers have failed.

But it’s not a device for coffee snobs. It’s best suited for those who appreciate the convenience of a Keurig and aren’t overly picky, or for those who would naturally load up their cold brew with milk and sugar or other flavorings. Cumulus doubles this flavored syrups from Orange Piloncillo to Cinnamon Demerara.

Photo: Cumulus