Key takeaways

• Coffee is mildly acidic (average pH ~5), less acidic than orange juice (pH 3) or beer (pH 4).
• In speciality coffee, acidity is a positive trait, referred to as “brightness” or “vibrancy.”
• Dark roasts are lower in acidity, while light roasts are higher.
• Higher altitude beans result in more acidic, flavourful coffee.
• Arabica beans generally have brighter acidity than Robusta.
• Choose dark roasts, use cold brew methods, or add milk to reduce acidity.

Coffee is certainly acidic. But lots of things are. Here, we’ll go through just how acidic and what that really means, how you can make yours more or less acidic, and what goes on behind the scenes to change acidity levels in coffee. 

How acidic is coffee?

Acidity may not be the most appetising term for some. But it can often bring real benefits.

In speciality coffee (Pact’s scoring 84 points or higher), “acidity” is a positive attribute described as “brightness” or “vibrancy”, rather than “sourness” – think oranges, apples, lemons, and grapes. For many, coffee would taste flat without acidity.

At Pact, we like to see it as the “zing” or “sparkle” in a cup that makes the experience “unmistakable”.

But just how acidic is coffee? The simple answer is rather acidic. To demonstrate this, we’ll have to dip into a short bit of chemistry.

What’s the pH level of coffee?

Remember this from the GCSE classes? If you briefly switched off, don’t worry. To put it into basic terms, the pH scale refers to how strongly acidic or alkaline a solution is on a scale of 1 to 14. If it has a pH value of 7, it’s completely neutral.

Anything from 0 to under 7 is acidic. The average cup of coffee has a pH of around 5, making it less acidic than orange juice (pH 3) or beer (pH 4). For further perspective, a ripe apple has a pH level of 3-4, and a banana hits 5 on the scale.

Our direct trade model ensures we work exclusively with growers who pick only ripe cherries, which have a more balanced natural pH than underripe commodity beans. You can find out more about our direct trade model here.

Why does some coffee taste less acidic than others?

This depends a lot on the preparation, as there are a lot of different acids inside the green coffee bean – citric, lactic, malic, acetic and quinic, to name just a few.

There are several factors to consider when you’re looking for a more or less acidic coffee:

Is dark roast coffee less acidic than light roast?

Chlorogenic acids are the primary compounds that break down during roasting, which is why roast level affects perceived acidity. It’s up to the roaster if they’d rather disguise or highlight that acidity. 

A heavier roasting process can bring more bitter acids into the coffee. So if you’re going for an inexpensive, heavy-roasted coffee, you’re likely to lose a lot of the brightness.

Also, most of the more pleasant acids lose their concentration in the roasting process. So if you opt for a lighter roast, you’re going to get a lot more of that fruitiness.

Discover which light-roast coffees are on the Pact menu this month.

What difference does altitude make to acidity?

There’s a reason that we list the altitude behind every coffee on our website.

Lower-altitude coffee will lack character and have very little acidity, while what’s made higher up will have much more interesting flavours and plenty of acidity.

If you want to taste the benefits of lofty coffee beans, look no further than our range from Colombia.

Is Arabica or Robusta more acidic?

The Robusta tree can grow at lower altitudes, is easier to tend to and is more resistant to tough weather conditions than Arabica. For this reason, it’s significantly cheaper to produce Robusta beans.

But Arabica beans are worth the effort and expense – they usually have a much brighter acidity, not to mention better flavours. That’s why you’ll only find Arabica coffee at Pact.

What coffee should I buy if I want a low-acidic coffee?

Dark roasts are the best way to go. Our coffee experts roast with precision in our roastery to carve out incredible chocolatey, nutty notes while muting sharp acidity – whether that’s for filter or espresso. 

For filter coffee, coffees like Terras Altas are an all-round delight. After an espresso? Our Bourbon Cream Espresso and Fruit & Nut Espresso blends are perfect for the job.

What coffee should I buy if I want a high-acidic coffee?

Light roasts are your go-to for this. Not only are they grown at higher altitudes, which encourages a brighter profile, but our roasters delicately roast the beans to highlight that character, so what you drink is a perfect expression of the farm it’s from.

Rwandan coffee is a Pact favourite in terms of desirable acidity – we keep going back for its consistent citrus and floral notes, finessed by the exceptional growers we work with there.

But whether you prefer low- or high-acid coffees, our roast-to-order model ensures the coffee arrives at your door at its natural peak, so you’re always experiencing it exactly how it was intended.

How to make a more or less acidic coffee

Acidity levels will be harmless for the vast majority of coffee drinkers. But if you’d rather lower them, there’s a lot to be done in the kitchen, too:

Ditch tradition with a cold brew

Many studies show that cold-brewed coffee contains significantly less acidity than a warm cup. And we have a handy guide on how to make yours at home.

Find your perfect grind size

Not all compounds are extracted at the same time from coffee grounds. So getting your grind size just right is key to both increasing and decreasing acidity. If you’ve got your own grinder, take the time to experiment and taste away!

Try precision brewing with the AeroPress

A fantastic way to control extraction and acidity is through precision brewing methods like the AeroPress. Our AeroPress brew guide walks you through how to make it delicious.

FAQs

Is cold brew coffee less acidic? 

Yes, significantly. Because cold brew uses cold water rather than hot, the extraction process works differently, drawing out fewer of the acidic compounds found in coffee. The trade-off is time – cold brew needs 12-24 hours to steep, but the result is a smoother, mellower drink that’s well worth the wait. Check out our guide on how to make your own at home – perhaps the best kept secret for those with sensitive stomachs.

Does milk reduce the acidity in coffee?

It does, a little. Milk contains calcium, which naturally neutralises some of the acids present in coffee, which is why a flat white or latte can taste noticeably smoother than a black espresso. The effect isn’t dramatic, but if you find black coffee a touch too sharp, adding milk is a simple and delicious way to take the edge off. 

What is the least acidic coffee at Pact? 

If acidity isn’t your thing, head straight for our darker roast profiles. Our roasters work precisely to bring out rich chocolatey and nutty notes while naturally muting sharper acidity. For filter drinkers, Terras Altas is a wonderfully smooth all-rounder. If you’re pulling espresso shots, our Bourbon Cream Espresso and Fruit & Nut Espresso blends are both excellent choices – full of rich flavour, but easy on the brightness.