The Hugely Popular Beverage You Shouldn't Pair With Fermented Food

Coffee may be a widely beloved morning beverage (check out our ranked popular coffee brands to see which we place on the highest pedestal), but it's one of the worst things you can drink alongside fermented food, whether you buy them in the store or ferment foods yourself at home. While both are praised for their bold flavors and health benefits, the pairing doesn't play well on the palate. That's because coffee — especially black coffee — is naturally acidic and bitter, and when combined with tangy, fermented foods like kimchi, miso, or sauerkraut, the result is an unpleasant flavor clash.

Fermented foods are already intense on their own, full of lactic or acetic acid and savory funk. Add coffee into the mix and those sharp, sour notes get amplified in all the wrong ways. The bitterness in coffee becomes more aggressive, and fermented flavors can taste different as a result. Even a spoonful of yogurt or a bite of sourdough toast can throw your morning brew into weird-tasting territory. 

We spoke with coffee expert Eric Gantz, co-founder of Verena Street Coffee Company, on this topic, who agrees that the glutamates and acids in fermented food are a bad mix with coffee. He said, "They tend to flatten out the cup and can leave a weird salty or tangy clash." So if your breakfast ever left your coffee tasting oddly harsh, fermented food was likely the culprit.

Coffee gets much of its signature edge from chlorogenic acid and bitter compounds, which are usually balanced out with fat, sweetness, or a clean-tasting dish. But fermented foods — rich in their own acids and bold umami — don't offer that balance. Instead, they compete, and they aren't the only foods that don't mix well with coffee. That competition disrupts the subtle, complex chemical reactions that normally give coffee its depth and smooth finish.

If you're chasing better flavor (and a better breakfast), it's worth rethinking your timing. Enjoy your cup of coffee before or after fermented foods — not during. And if you're pairing something funky and fermented with a beverage, opt for a mild green tea, sparkling water, or regular water — anything that won't spark an acid war in your mouth. Both coffee and fermented foods deserve their own spotlight — just not at the same time.