Is the Acidity in Specialty Coffee Called Coffee Acidity? What is the Acidity of Coffee and Is There Scientific Evidence?

When you taste a coffee with good acidity, you might find it hard to describe what you're experiencing — especially if you're not fluent in coffee terminology. At FrontStreet Coffee, whenever we cup new beans, the roasters patiently explain the acidity in the coffee: its flavor profile and what type of acid it contains.

When we first started cupping and drinking coffee, we couldn't tell the specific acids apart — malic acid, citric acid, tartaric acid, or the acidity found in cranberries. Distinguishing between these different types of coffee acidity is genuinely hard.

I once found "flavor profiles" and the "flavor wheel" the most baffling of all. To me, they all tasted like coffee. Sure, some were more acidic than others and some more bitter, but they were still coffee. Today, FrontStreet Coffee will talk you through coffee acidity.

Coffee Acidity

Acid is a chemical substance characterized by a sour taste — in fact, the Latin word "acidus" literally means "sour." Acidic aqueous solutions have a pH below 7, and the lower the pH, the higher the acidity.

Acids occur naturally in many foods: lemons, vinegar, yogurt — and coffee. Coffee alone contains hundreds of different acidic compounds, from familiar ones like citric acid to obscure ones like 4-monocaffeoylquinic acid. FrontStreet Coffee will only cover the main acids that affect taste.

Citric Acid

As the name suggests, citric acid is found in high concentrations in citrus fruits — it can account for up to 8% of their dry weight. It is the most common acid in all fruits and vegetables and one of the easiest to identify.

Malic Acid

The taste of malic acid is often associated with green apples (it comes from the Latin word "malum," meaning "apple"). You'll find the purest form in rhubarb, where it constitutes the main flavor.

In the culinary world, malic acid is often linked to limes, but it's easier to think of it as an "unripe fruit flavor." Its concentration typically decreases as fruit ripens, which is why green foods like green grapes, kiwis, or currants get classified this way.

Tartaric Acid

Tartaric acid is typically associated with grapes, where it's highly concentrated — but that's not the only place you'll find it. Its salt, potassium bitartrate (better known as cream of tartar), forms naturally during winemaking and is often used as a leavening agent in food preparation.

In terms of taste, tartaric acid's most notable trait is its mouthfeel: it triggers a flood of salivation and leaves an astringent aftertaste. In fact, it's one of the main ingredients in "super sour" candies and gobstoppers.

Acetic Acid (also known as Ethanoic Acid)

Acetic acid is special. Besides a very distinctive unpleasant taste, it has a pungent, unpleasant odor. At low concentrations this becomes a pleasant sharpness or lime-like brightness; at higher concentrations, the taste and smell read as fermentation.

That distinctive taste and smell — especially paired with other flavors, particularly sugar — can produce wine- or champagne-like qualities.

pH Value and Coffee Acidity

The simplest way to understand coffee acidity is to treat it as an abstract concept. "Orange acidity" doesn't mean your coffee tastes like oranges; it means it's sour the way an orange is sour.

With that framing, tasting notes suddenly make more sense. Since blueberries are less acidic than lemons, a coffee with "blueberry acidity" is undoubtedly less acidic than one with "lemon acidity." Makes sense, right?

But within the pH range, some fruits have similar pH values despite tasting completely different — apples and oranges, for example. How does that work?

For apples and oranges, the primary acids differ: green apples are dominated by malic acid, while oranges are full of citric acid.

Imagine a lovely, bright, light-roast African coffee. When brewed, its pH reads 4.6 — so we're looking at grapes, peaches, plums, pineapples, and so on. Then you notice it leaves a tartaric astringent sensation in your mouth. You could call that "grape acidity," or anything from the sour stone fruit family (sour cherries, plums, etc.). Combine grape acidity with the fermented character of acetic acid, and you might even describe a wine-like acidity.

Similarly, low-pH citrus notes can be read as "lemon acidity," while higher pH values lean closer to orange. Malic acidity at lower pH might be lime; at higher pH, rhubarb, green apple, or even grapefruit. Once all of this clicks, cupping and understanding coffee acidity becomes much easier.

Improving Your Palate

It always helps to practice by tasting a variety of flavors. Nothing sharpens your perception of coffee acidity like tasting acidic foods!

After getting a clear sense of pure acids, move on to real foods. Lay out a big plate of fruits, vinegars, even wines, then sort them by the acidity you taste.

The thing about cupping is that once you've mastered it, it both deepens your understanding of coffee and makes drinking it more enjoyable. Acidity descriptors may look daunting, but once you know what to look for, they're surprisingly easy to distinguish. Before you know it, you'll be an acidity expert.

FrontStreet Coffee Recommendation

All this talk of acidity brings up a practical question: what if you want balance? During roasting, three elements decide a coffee's final flavor — sourness, sweetness, and bitterness. The darker the roast, the more bitter and full-bodied the cup; the lighter, the more acidic and delicate. If you're after a balanced profile, medium-roasted beans are the place to start.

FrontStreet's Brazil Fazenda Rainha is a perfect example. If you dislike both sourness and harsh bitterness, this Yellow Bourbon — a variety unique to Brazil, the world's largest coffee producer — offers a quietly sweet cup. Medium roasted, it reveals creamy peanut, chocolate, toasted bread, and sugarcane aromas and sweetness, working equally well as a pour over, in a moka pot, or through an espresso machine. For a fruitier take on medium roast, try FrontStreet's Strawberry Sugar Gesha blend, which unites two famous origins: honey-processed Costa Rica and washed Panama Gesha. The medium roast preserves both the orange-blossom honeyed character and a rounded sweetness — refreshing on the palate, and versatile enough for cold brew, pour over, or espresso.

Two more medium-roast classics round out the lineup. FrontStreet's 2013 Yunnan Natural Typica, a flagship of Chinese specialty coffee, delivers the authentic Yunnan arabica character — nuts, brown sugar, black tea, and dried apricot in a soft, balanced cup, great in a pour over, cold brew, or drip machine at a very friendly price. And the "Emperor of Coffee" — FrontStreet's Jamaica Blue Mountain No. 1, grown from Typica on Jamaica's Blue Mountains — is medium roasted to fuse acidity, bitterness, sweetness, and body into one elegant whole, with chocolate, roasted nuts, cream, and caramel on the entry: a level of balance no other coffee can match.