Is Coffee Acidic? Understanding Your Brew's pH Level

When we wake up in the morning to the rich aroma of coffee brewing, we're not usually thinking about its acidity. But the acidity of coffee is a crucial component of your brew's unique flavor profile and how it interacts with your health. So, let's dive in and unravel the mystery of coffee's acidity, shall we?

What Determines the Acidity of Coffee?

In the world of coffee, acidity refers to the flavor notes that make your coffee taste bright, vibrant, or wine-like. But in the scientific realm, acidity is determined using the pH scale. This scale ranges from 0 to 14, with any solution registering from 0 to 7 considered acidic. Most coffee varieties are indeed acidic, with an average pH value of 4.85 to 5.10. This acidity is part of what gives coffee its unique flavor profile, contributing to the complexity we adore in every cup (​1​).

The brewing process releases nine major acids from coffee beans, contributing to coffee's distinctive flavor. These include chlorogenic, quinic, citric, acetic, lactic, malic, phosphoric, linoleic, and palmitic acids. But don't assume that all coffee is created equal when it comes to acidity. Several factors can alter the pH level of your brew.

Roasting and Acidity

How your coffee is roasted significantly influences its acidity. A study has shown that the longer and hotter coffee beans are roasted, the lower their chlorogenic acid levels. What does this mean for you? Lighter roasts tend to be higher in acidity, while darker roasts are lower.

This is noticeable by taste alone, but the science backs it up. For most of us that like specialty coffee, we prefer the more acidic, bright coffees, but that isn’t the case for everyone. Or, if you’re extra sensitive to the acidity but like the flavor of light coffees, there are a few other factors that can influence the acidity levels.

Extraction and Acidity

Basically, the more you increase extraction, the more you increase acidity in your coffee. Generally, the three levers you can pull to affect extraction are either grind size, temperature, or brew time—all of which can differ by brew method. For example, cold-brewed coffee has been found to be significantly lower in acidity than hot coffee. 

In regards to grind size, the smaller the grinds, the greater the surface area exposed relative to volume, leading to a higher extraction. So, if you're using a finer grind, you might end up with a more acidic cup of coffee.

How Does Coffee's Acidity Affect Health?

While the acidity of coffee is perfectly fine for most people, it may aggravate certain health conditions in others. These conditions include acid reflux, gastric ulcers, and irritable bowel syndrome (IBS). 

Coffee's effects on these conditions are mainly attributed to its acidity and slight laxative effect in some people. Although coffee hasn't been shown to cause these conditions, if you have been diagnosed with one of them, you might want to avoid coffee or opt for less acidic varieties. 

Reducing the Acidity of Coffee

If you love coffee but find that the acidity doesn't sit well with you, there are ways to reduce it. Opting for cold brew coffee or choosing darker roasts are some strategies you can use to lower the acidity of your coffee, allowing you to continue enjoying your morning ritual without discomfort.

Anecdotally, I’ve also known people who don’t notice their symptoms if they add a little cream or milk to their coffee.

The Bottom Line

With an average pH of 4.85 to 5.10, most coffees are rather acidic. While this doesn't present a problem for most coffee lovers, the acidity can negatively affect certain health conditions in some people, such as acid reflux and IBS. But remember, there are several methods of reducing acidity, so you can still enjoy your cup of java while mitigating the side effects of its acidity.

Now that you're armed with this knowledge, you can explore and experiment with different coffee roasts and brewing methods to find the perfect balance of acidity that suits your palate and agrees with your body. Happy brewing, coffee lovers.