Nitro cold brew is a variation of cold brew coffee that uses nitrogen gas to create a unique texture. It was first introduced by Cuvee Coffee in Austin, Texas, in 2012. The coffee is infused with nitrogen through a pressurized valve, similar to how Guinness stout is served. Because nitrogen bubbles are much smaller and less soluble in water than carbon dioxide bubbles, they create a thick, creamy mouthfeel and a beautiful 'cascading' visual effect as the bubbles rise. This process also reduces the perceived bitterness and acidity of the coffee, making it taste naturally sweeter without the need for added sugar or milk. The science of the 'cascade' is caused by a circular current in the glass where the bubbles rise in the center and sink at the edges.