Why Does My Coffee Taste Acidic?

When I was a barista, customers often told me “I don’t like acidic coffee.” 

While it’s true that a coffee’s acidity can be overpowering and out of balance, I believe most of the time those customers meant that they didn’t enjoy harsh, bitter, and astringent tastes in their coffee. These flavors are often associated with chlorogenic acid, which readily breaks down into bitter compounds like quinic acid and caffeic acid, so technically they weren’t wrong. 

But when coffee professionals refer to a coffee’s acidity, they’re typically talking about a bright, zippy taste sensation on the palate. 

Think of a sour candy, a ripe plum, or even the phosphoric sting of a Coca-Cola. Each of these tasting experiences offer acidity to balance the sweet and bitter flavors. 

Without acidity, life would be flat and dull. Coffee is no exception. 

Why is coffee acidic? 

Coffee is acidic because it contains organic acids such citric, malic, and acetic acid. These are the same acids found in fruits like apples, strawberries, or pineapple. 

There is some debate about the difference between acid content and perceived acidity. For example, a Brazilian coffee and a Kenyan coffee will show similar amounts of citric acid when analyzed in a lab, but Kenyan coffee is widely considered to have more acidity than Brazilian coffee. The answer might have something to do with polyphenol levels or flavor association, but suffice it to say coffees from higher elevations (i.e. above 1600 MASL) tend to have more perceived acidity in the cup-- think of coffees from Ethiopia, Kenya, and regions of Colombia like Huila. Lower-elevation coffees from places like El Salvador or Brasil tend to have less perceived acidity. 

Acidity and Extraction

Organic acids are simple compounds that dissolve quickly during brewing.

An exercise I do with the students in my SCA courses illustrates this. It’s easy to try at home if you have an Etkin 2-cup Dripper and at least five coffee cups. 

I start brewing the coffee with the dripper on the first cup. After about a minute I move the dripper to the second cup (the double wall on the Etkin Dripper is nice for this part!). Around 30 seconds later I move the dripper to the third cup and continue like this until the entire brew is divided between the five cups. 

Students are often surprised to discover that the first two cups are intensely sour, but by the third cup there is almost no perceived acidity. All of the acids were dissolved in that first minute and thirty seconds. 

This example illustrates why underextracted coffees tend to taste sour. They have acidity, but they lack the sweeter and bitter flavor compounds that dissolve later in the brew. The best coffees have a combination of all of these flavors.

So if your coffee tastes too acidic, try lengthening your extraction time. An easy way to do this is to grind a little finer or to pour the water in slower, smaller increments. 

Acidity and Roast Degree

Not everyone wants a squeeze of lemon in their iced tea. Some people simply don’t want any acidity in their coffee. If that’s the case for you, sticking to darker roasts of lower-elevation coffees might be your best strategy. 

Acids like citric acid and malic acid start to break down around first crack in the roasting process. By second crack, there’s very little left. Conversely, lactic acid will increase as the roast goes on, which is one of the reasons dark roasts tend to have more body. 

As roasting trends have tended lighter and brighter, I find some roasters seem to prefer a more sour cup. Acidity might be considered a positive trait, but it’s possible to have too much of a good thing. 

Personally, I adore coffees with a bright, sparkling acidity that complements a bouquet of other tastes, flavors, and aromas.

At the end of the day, there’s no right or wrong way to drink your coffee. So don’t be afraid to experiment with different coffee origins, roast degrees, and pour-over recipes to find the acidity level that is right for you.