To make nitro coffee, nitrogen gas is pumped into cold-brew coffee, resulting in a smooth and creamy mouth feel that is reminiscent in appearance and texture to a Guinness beer. Beer brewers traditionally add carbon dioxide for fizz, but they’ve used nitrogen for certain richer or roasted stouts and ales for a better complementary flavor. Coffee brewers picked up on that process to create nitro coffee.

For nitro coffee, operators must install nitro taps fitted with restrictor plates. The high-pressure tap forces the coffee through tiny holes, re-aerating the nitrogen and giving it a cascading effect as it’s poured into the glass. Nitro coffee is creamier than traditional coffee. The reason: Nitrogen doesn’t dissolve easily in water, so it forms a dense foam when aerated to create a thicker product. Nitro coffee’s smoothness reduces the need to add milk or creamer—a benefit for consumers avoiding dairy.