When you made that cup of coffee, you had every intention of sitting down, taking a moment to yourself, and enjoying the warm liquid as it ran down your throat. But then… life. And now, your once fragrant cup of joe is icy cold (or worse: lukewarm).
You’re tempted to still drink it well past its best because you want the caffeine and don’t have time to make another. “How bad can it be?” you think to yourself. Well, the answer is, very.
Coffee beans naturally contain acids and compounds that release bitterness when heated up. These chlorogenic acids produce quinic acid (think quinine in tonic water) and caffeic acid, both of which possess a bitter, astringent taste.
Freshly-brewed coffee may contain a hint of bitterness, but it is usually balanced with other notes to give it a complex flavor. The problem arises when that coffee is reheated—like in a microwave—and more quinic and caffeic acids are produced.
Coffee tastes best when consumed within an hour of being brewed as the flavor changes as it cools. But, if you must drink it and don’t want to totally torture yourself, there is one way to go about it.
Pour your cold coffee into a small saucepan, and warm it up on the stove over medium heat. Don’t use full heat as this will burn the coffee. Once it starts to gently simmer, remove the coffee from the stove and drink as soon as possible.
