Few things have risen to fame as quickly and as publicly as cold brew coffee - something that many of us love to consume yet few of us truly understand. What’s the difference between this beverage and a plain iced coffee (is there one?), and why can major chains charge upwards of an entire dollar extra for a “nitro” cold brew?
In some ways, cold brew is exactly what it sounds like. Instead of using heat to brew the coffee, the beans are left to steep in room-temperature water for 18-24 hours before the grinds are filtered out and the resulting liquid is served. Iced coffee is produced via a much quicker process - it’s simply a cup of coffee that has been brewed the traditional way (i.e. with heat), allowed to cool, and then added to ice.
With modern-day coffee makers pumping out a warm cup of joe in less than 30 seconds, it may seem confusing why anybody would voluntarily plan an entire day in advance just for their morning cup of cold brew. But consumers’ growing preference for the newest addition to the coffee market is not entirely unwarranted -- there’s a science behind the taste.
All coffee, regardless of the way it’s brewed, is created when acids, oils, and other chemical compounds are released after the beans react with water. Collectively these are known as “coffee solubles,” and the use of heat dramatically increases the rate of this reaction and thus the concentration of these solubles in the finished product. On one hand, the increased volatility at high temperatures gives the pleasant aroma of a fresh cup of coffee as well as the strong, full-bodied taste associated with the hot version of this drink. But this comes at a cost -- heat increases the rate of oxidation and degradation, including the breakdown of cholinergic acid into compounds that cause bitterness.
With this in mind, it’s easy to see how the process of brewing cold brew can alleviate some of the notorious taste complaints of those who can’t stand a hot cup of black coffee. The lengthy time required to create cold brew is necessary to offset the decreased solubility of coffee solubles in cooler water, but it also largely prevents the reactions that spawn bitterness and acidity.
However, cold brew requires twice as many beans to brew as a traditional cup -- a fact that cafés use to justify the significant upcharge on a hot cup of coffee’s cooler counterpart (pun intended). The already-way-too-expensive price tag is often jacked up even higher for “nitro” cold brew, which has the added benefit of mimicking a draught beer in terms of carbonation and “that silky feeling.” Infusing the coffee with nitrogen gas and serving it straight from the tap (without ice this time) may be a fun treat and Stumptown’s claim to fame, but it’s not always worth the extra dollar every single time you need a caffeine pick-me-up.
Your hipster friends aren’t totally crazy -- there is some science behind why people prefer cold brew over a grab-and-go cup of hot coffee from the local drive thru or somebody’s old Keurig. I’m not above this, and as somebody who hates the overly acidic taste of cheap coffee, I’m partial to this cold brew movement. It’s now widely available in almost every café nationwide, and 7-Eleven recently launched a canned version with a twistable base that “cools itself” so that consumers can enjoy their beverage any time of day. This sounds dramatic, but I would be lying if I said I wouldn’t buy one (or at the very least, think about buying one).
Disclaimer: I am not a licensed nutritionist nor a registered dietician. The opinions expressed in this article are my own, and each individual is ultimately responsible for his/her dietary and nutrition practices. Please consult a physician before starting a new dietary program.