Cold brew coffee is thought to be less acidic than regular coffee brewed with hot water.
Acidity plays a big role in taste, but what does this mean, exactly? Why is cold brew coffee less acidic than its hot counterpart, and what else affects acidity in coffee?
We'll answer these questions on cold brewed coffee below.
Acidity is one of several components of coffee taste—along with aroma, body, boldness, bitterness, and sweetness. When people describe coffee as acidic, they often mean it has a bright, tangy, or crisp flavor profile.
The acidity level can also refer to the chemical composition of coffee, specifically its pH level. Coffee's pH is usually between 4.5 to 5.5. A lower number would be a more acidic coffee, and a higher number would have a more neutral flavor.
The hot brewing process tends to have more powerful extractions compared to coffee brewed with chilled or room-temperature water.
Most cold brew coffee methods call for steeping ground coffee and water for at least four hours and up to 24 hours. The extended cold brew coffee extraction time reduces the natural acidity of coffee beans. While soaking for longer might result in a more concentrated brew, the flavor may be milder, as acidity is tempered and sweetness comes through.
According to research by the Specialty Coffee Association (SCA), there might also be certain chemical components of coffee that aren't released when brewed at lower temperatures. This could be why cold brew coffee typically has a higher pH than traditional hot brewed coffee, meaning it's less acidic.
It's unclear exactly why a cold-brewing method results in coffee with a lower acidity level. And beyond water temperature, many factors can affect taste and pH when brewing coffee. We'll get to these shortly.
One theory is that the chemicals extracted from coffee grounds are more soluble in hot water. So a traditional hot brewing method may release acidic compounds more quickly or efficiently than cold water—and a cold-brewing technique might not even extract all the compounds.,
Low-acidity cold brew coffee might have a pH of 5.5 or higher. Meanwhile, drip coffee made with hot water may have a pH closer to 4.8.
Remember, a higher pH number actually means lower acidity, and a lower pH points to a more acidic flavor.
Other things can affect the acidity of coffee, including:
● Bean origin — When comparing Robusta vs. Arabica coffee, Robusta coffee beans often have a slightly bitter, sometimes earthy taste. Arabica coffee beans, thought to originate from Ethiopia, tend to have a smooth and bright flavor profile with more acidity.,
● Roast level — Coffee beans are naturally acidic. A lighter roast means a shorter roasting time, so more of the natural acids of the beans are preserved. Darker roasts are generally less acidic but typically have a more robust or bitter taste.
● Brewing time — A shorter brew time tends to produce more acidic coffee. Meanwhile, a longer brew time allows for more extraction, resulting in less acidity but a bolder flavor.
If you prefer the taste of a less acidic coffee, cold brew might be the way to go.
As mentioned, Robusta coffee beans are usually less acidic than Arabica. But the roast level matters too. A light roast will take longer to reach a more neutral acidity because the beans are closer to their naturally acidic state.
So your best option for low-acid cold brew is medium or dark roast Robusta coffee beans. For optimal flavor, pick up freshly roasted beans from your local roaster or coffee shop.
A higher coffee-to-water ratio will generally create a more acidic flavor. However, steeping cold brew for longer (closer to 24 hours) in cold water can give it more time to neutralize the acidity and provide a smoother taste.
There are other ways to reduce the acidic flavors in coffee. During the cold brewing process, you can steep it using alkaline water, which has a higher pH than most drinking water, meaning lower acidity.
You can also try adding a pinch of baking soda directly to your cold brew coffee before serving it. Baking soda is alkaline, so it can help neutralize acidic flavors.
As you're probably well aware, those who find coffee too bitter, strong, or acidic often mix it with milk. Cow's milk and plant-based milks like almond milk and oat milk can make the flavor more appealing and easier to drink.
When making cold brew coffee at home, think about what you prefer in terms of flavor and concentration. If you're aiming for a low-acid finish, choose Robusta beans with a dark or medium roast.
Cold brew coffee traditionally takes several hours to make. But you can craft your own in just a few minutes with an espresso machine with cold brew extraction technology.
Sources:
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