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Home » Can You Microwave Coffee? (You’ll Be Surprised By The Answer)

Can You Microwave Coffee? (You’ll Be Surprised By The Answer)

We’ve all been there: you accidentally forgot about your cup of coffee and now it’s cold. You’re wondering if you can just pop it in the microwave for a bit to warm it up. A totally reasonable question.

And you can! But it might not taste very good. In this article, we’ll go over why coffee doesn’t taste so good after it’s reheated and why you can actually reheat coffee in the microwave.

Is It Bad To Reheat Coffee?

The bottom line is that reheated coffee isn’t going to kill you. It won’t give you food poisoning or make your stomach upset or anything like that. In that sense, it’s certainly not bad to reheat coffee. However, no matter how you reheat coffee, it will taste pretty awful.

The flavour profile of coffee comprises different volatile compounds that come out when the beans are roasted, ground, and then brewed. That means that as coffee starts to cool down, the compounds that make it taste sweet, balanced, and delicious break down. When those compounds break down, your coffee starts to taste bitter.

When you reheat coffee, all of the good stuff…starts to disappear and the resulting cup leans toward the more bitter components.

The bitter compounds are the last to break down. Once all the good compounds are gone, you’re left with a terrible cup. But don’t be discouraged! Not all reheating methods are created equal. And microwaving coffee is a great way to go.

How to microwave coffee

Why It’s Okay To Microwave Coffee

We know that reheating coffee changes the taste for the worse. But it’s not the end of the world. Especially if your coffee isn’t totally cold yet. If your coffee still has some warmth and isn’t room temperature, then microwaving it won’t have as pronounced a change.

Instead, your coffee will taste relatively similar. Microwaving coffee adds heat evenly throughout your cup instead of only in one spot on a stove or a cup warmer. Just make sure that you don’t overheat your coffee. Remember to consume coffee at around 60 degrees Celsius (1).

The Best Way To Reheat Coffee

There are plenty of ways you could go about reheating mugs of coffee. A hot plate, on the stove, double boiler, etc. But the best way, across multiple sources, is actually the microwave.

While no one is certain why, the leading theory is that the microwave adds heat evenly, as stated earlier. This means that no part of your coffee gets too hot (above 94 degrees) and burns (2). But you mustn’t microwave your coffee too much.

Too much microwaving will make your coffee taste even worse.

Alternatives To Reheating Coffee In The Microwave

The best way to avoid reheating coffee is not to let it get cold in the first place. Drinking your coffee quickly means you get the best tastes and the most rounded flavour profile. But sometimes, it’s unavoidable.

Preheating your mug is a great way to keep your coffee stays hot for longer. You can fill your mug with hot water before you add coffee or use a smart mug to keep your mug hot.

The lower-tech version of the smart mug is a trusty thermos. But note that you should always use a clean thermos and not let coffee sit in your thermos for a long time, and coffee will eventually go bad and get mouldy.

The Verdict

You can absolutely reheat coffee in the microwave. And yes, it is the best way to reheat your coffee if you absolutely must reheat it.

Not letting your coffee go cold in the first place is still the best option. Any reheated coffee will result in a loss of good flavour and a more bitter cup than might be pleasant. However, reheating coffee isn’t bad for you; if you must, then you must!


You should microwave coffee in three bursts of 15 seconds each. Between each burst, gently stir your coffee to ensure that all your coffee heats evenly and nothing burns.

You can make instant coffee in the microwave without losing much flavour. The best way is to mix one serving of instant coffee with 6-8 oz of water. Then put it in the microwave for bursts of 15 seconds, stirring in between until all the granules are dissolved.

It’s not recommended to reheat coffee the next day. Once the coffee is room temperature, making a fresh pot is much tastier than reheating cold coffee. But reheating day-old coffee isn’t bad for your health.

  1. Pipunic, A. (2022, April 5). Should you microwave coffee? Perfect Daily Grind. Retrieved March 17, 2023, from https://perfectdailygrind.com/2022/03/should-you-microwave-coffee/
  2. Brones, A. (2019, May 2). How important is water temperature when brewing coffee? Kitchn. Retrieved March 17, 2023, from https://www.thekitchn.com/do-you-need-to-worry-about-water-temperature-when-brewing-coffee-smart-coffee-regular-joes-216229/
Craig C.
My three favorite things in life are coffee, rock climbing, and spending time outside. I'm part of the AeroPress fan club and an advocate for the Oxford comma.

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