The popularity of nitro cold brew coffee has grown so steadily over the past few years that skeptics may be tempted to call it a fad. But those of us who enjoy it have come to realize that nitro cold brew is more than just a variation of the standard cup of joe—it’s a new beverage experience unto itself, different in both taste and texture. And we have science on our side to make the case.
Brewing coffee at cold temperatures produces an end product that’s sweeter and less acidic that coffee brewed with hot water. This is because the chemical compounds in coffee break down differently. As water comes into contact with coffee grounds, it extracts the “coffee solubles,” which give coffee its taste and caffeine content. Hot water pulls these solubles out of the grounds more quickly than cold water, allowing you to brew it much faster. But boiling water also degrades and oxidizes the chemical compounds in the coffee, which gives hot-brewed coffee its bitter and slightly sour taste. This oxidation and degradation occur much slower in coffee brewed with cold water, so the result is a drink that is neither bitter nor acidic.
The addition of nitro gas adds yet another layer to the magic of cold brew. By using a pressurized valve, like the one in the uKeg Nitro, to infuse nitro gas into the cold brew, the beverage takes on a velvety texture. Nitro gas isn’t as soluble in liquid as, say, CO2. So, whereas CO2 produces the bigger bubbles that we see in carbonated beverages like beer and soda, nitro gas creates much smaller bubbles. This army of teeny, tiny bubbles produces the creamy mouthfeel, and creates the cascading effect when the cold brew is poured and the bubbles rise from the bottom of the glass to the top.
If you want to go deep into the chemistry of nitro-infused cold brew, check out this article. But for a quicker, quirkier explanation, Bill Nye the Science Guy does a great job of explaining it in this video he created in partnership with Starbucks.
Nitro also preserves the flavor of the cold brew by preventing further oxidation, which keeps your batch of cold brew fresh longer!
All of the above makes the case for nitro cold brew being its own unique beverage. It also has another potential benefit. Because the coffee has a naturally sweeter flavor and creamier mouthfeel, many people find that they can forgo the cream and sugar that they put in their regular cup of hot-brewed coffee. This makes it a healthier alternative for your daily pick-me-up.