It’s no secret that much of the world runs on coffee. Humanity’s love affair with caffeine has produced some fantastic innovations in coffee-making over the years.
One of the most recent variations to hit the scene is cold brew coffee. Contrary to popular belief, cold brew coffee is not merely cold coffee – it’s a different drink altogether with some unique qualities.
What is Cold Brew?
With the traditional hot coffee brewing method, you brew coffee by submerging ground coffee beans in hot water, usually through a drip system or French press. Even a glass of iced coffee starts off this way, with the ice added later to cool your drink.
With the traditional hot-brewing method, coffee can be ready within minutes. On the other hand, cold brew coffee is made by mixing a larger amount of ground coffee with cold water and leaving it to sit. The brewing process can take upwards of 12-24 hours.
Once the process is complete, the coffee grounds are strained out, and you will be left with a generous helping of cold, concentrated coffee.
Caffeine in Cold Brew vs. Hot Coffee
There’s a reason why coffee is a breakfast staple. Caffeine activates the regions of the brain that control tiredness and energy by blocking the actions of adenosine, which is why a cup or two in the morning can jump-start your day.
Caffeine is a water-soluble compound. Therefore, it doesn’t matter if water is hot or cold – caffeine can be extracted from coffee beans in either environment. A 12+ hour brewing process means cold brew tends to be extremely concentrated compared to regular, hot coffee.
An ounce of cold brew coffee will almost always have more caffeine than an ounce of traditionally brewed hot coffee, simply because it takes more coffee grounds to make it and it brews for a longer time. However, cold brew is often diluted with cream, milk, or water. Considering this, a serving of finished cold brew sometimes has similar amounts of caffeine as regular coffee.
Antioxidants in Cold Brew vs. Hot Brew
Antioxidants are molecules that protect cells from free radicals, reactive molecules with extra electrons that are linked to heart disease, diabetes, and cancer. The human body produces some free radicals as part of its immunity defense, but also as a side effect of oxidation.
Cellular damage can occur when the balance between free radicals and antioxidants is disrupted, and – scientists generally agree – it’s good for humans to consume antioxidants from other sources.
The good news? Coffee is the most significant source of plant-based antioxidants in the Western diet.
A 2018 study examined the difference in antioxidant content between samples of cold brew and hot coffee. When differences in the grounds-to-water ratio between brewing methods were accounted for, hot coffee has more antioxidant activity than cold brew coffee. These results suggest that water temperature has an effect on the antioxidant content of coffee, and hot coffee may be more nutritious than cold brew when it comes to antioxidants.
Acidity of Cold Brew and Regular Coffee
Acidity in coffee is what makes it taste bitter or sour. It’s also what can make coffee bad for your teeth.
It’s generally understood that hot coffee is more acidic than cold brew—up to 66% more. Acid gives coffee depth and dimension, but it can also cause upset stomach, heartburn, ulcers, and other gastrointestinal problems. Cold brew coffee, which has less acidity than hot coffee, doesn’t induce as many GI flare-ups in comparison.
The study also found a correlation between acidity and antioxidant activity in coffee. Not only was hot coffee more acidic than cold brew, it also had more types of acid compounds than cold brew. Researchers believe that hot water plays a role in the extraction of these acids as well as influencing antioxidant content.
All of this is to say: acidity and antioxidant content in coffee might go hand-in-hand. Acid in coffee might aggravate a sensitive stomach, but it might also be a sign of hot coffee’s nutritional benefits.
Overall Taste of Cold Brew and Regular Coffee
Because of differences in acid content, cold brew can taste mellower, less bitter, and even sometimes “sweeter” than regular coffee. This flavor profile makes cold brew “better” for many people.
The smoother taste of cold brew can also encourage people to start taking their coffee black rather than with cream and sugar. While adding a bit of milk or milk alternative can help curb coffee’s acidity and caffeine content, it’s probably easier to avoid added sugar with cold brew.
Refined sugar is considered a silent killer, with links to obesity, heart disease, and diabetes. Americans already consume significant amounts of sugar in their beverages, and adding it to coffee might cancel out any potential health benefits.
At the end of the day: which form of coffee is better? That depends on personal preference and your tolerance for acidity.
Science is still catching up with the differences between cold brew and regular coffee at the molecular level, but experts seem to agree that the differences are minor at best. Choose regular coffee for its quick brewing process and additional antioxidants or cold brew for its lower acid content and easy palatability. In the end, it’s the caffeine that matters, and both options have it in spades.
Gerard Paul writes about food & drink at ManyEats. He’ll happily take his coffee no matter how it’s brewed – at most any time of day or night.