Can You Microwave Coffee?

While coffee is an important part of our morning routine, sometimes a very busy morning can make us forget that we even brewed a cup. When we finally remember that we had a cup of coffee ready to drink all this time, it’s already too late as the coffee has gone completely cold.

At this point, you might be thinking about reheating your coffee, and that thought quickly leads to microwaving your coffee as it is the easiest way of reheating something. Since you’ve never done it before, you’re not exactly sure whether that is a good idea or not.

You can indeed microwave your cup of coffee to reheat it, but the taste will leave a lot to be desired. Coffee that is left out for a long time will start turning bitter, and reheating it will only make things worse by extracting even more bitter components.

Importance of Drinking Your Coffee Fresh

Drinking your coffee while it’s fresh ensures that you get the best coffee experience possible. As coffee loses freshness, it slowly becomes more undesirable to drink, and eventually becomes undrinkable.

Starting from the very first minute you brewed your coffee, it starts interacting with oxygen molecules, which starts a process called oxidation. As oxidation takes place, the acidity level of your coffee increases and your coffee starts becoming bitter. The components that give flavor to your coffee start losing their chemical integrity, and eventually, the taste of your coffee is completely ruined.

In just 30 minutes, you will already notice a difference in the flavor of your coffee in a negative way, and your coffee will most likely be cold. In a few (roughly 4) more hours, the oils in your coffee will start to turn rancid, which will cause the taste of your coffee to be even worse.

By drinking your coffee as soon as it’s brewed, you minimize the impact of oxidation and ensure that you get to taste the complete flavor profile of your drink.

Why Does Reheated Coffee Taste Bad?

We have mentioned the negative things that happen to your coffee when it stays out for too long, and reheating your coffee just adds insult to injury. If you think reheating your coffee will revive it and make it taste good again, we have bad news for you.

By reheating your coffee, you’re essentially allowing even more of the bitter components (such as quinic acid and caffeic acid) to extract, which makes your coffee taste even worse than before. While coffee being hot helps to hide the bad taste, at this point it’s just better to ditch your coffee and brew a new cup.

Coffee is very prone to losing its freshness, which is why it’s always recommended to buy fresh coffee beans in smaller amounts, grind only as much as you need to brew a cup, and drink your coffee as soon as you brew it.

Keeping Your Coffee Warm

Since reheating coffee isn’t really optimal, we have to take preemptive measures to ensure that our coffee doesn’t go cold and lose its freshness. With proper storage, we can slow the oxidation process down and keep our coffee warm enough to drink even if it has to stay out for some time. 

Let’s go over some tools which come in handy for keeping coffee warm.

Mug Warmer

Mug warmers are heated plates that you can put your mug on top of. While they don’t really do anything to stop your coffee from interacting with the air outside, they do a decent job at keeping your drink warm.

If you’re planning to drink your coffee slowly, a mug warmer will do the job for you. On the other hand, it’s not really a good tool to keep your coffee fresh for a long period of time.


A good thermos will do a great job of keeping your coffee warm and also seal it airtight, meaning that your coffee will stay fresh for longer.

While it depends on the quality, you should be able to keep your coffee fresh and warm for up to 24 hours with the help of a thermos. If you’re looking to prepare your coffee in the morning and drink it throughout the day, a thermos is a good choice.

Mug with Lid

As simple as it sounds, a lid actually does wonders when it comes to keeping your coffee fresh. These mugs are usually insulated, and the lid allows you to get an airtight seal.

While not exactly carry friendly like a thermos, it’s handy to have if you’re looking to keep your coffee fresh and warm at your desk. Depending on the quality, a mug with a lid will be able to keep your coffee as good as new for a good amount of hours.

Temperature Control Mug

Temperature control mugs do the best job when it comes to keeping your coffee fresh and warm, but they also come with a hefty price tag.

These mugs usually have the same qualities as a thermos but they are able to keep your drink at the exact temperature you set it to for a few hours since they contain a heating system. 

It’s definitely cool technology, but we feel like a high-quality thermos is good enough to keep your coffee at a desirable temperature for a long enough time.

Best Way to Reheat Your Coffee

If you still want to reheat your coffee through all the downsides which come with it, then let us help you do it in the best way possible.

It’s time to put the microwave aside, and use the good old stovetop for this one.

  1. Pour your coffee into a stovetop safe pot.
  2. Bring your stovetop to the lowest heat possible, and place your pot on the stovetop.
  3. Wait until your coffee is warm enough, and remove it from heat.

The trick here is to use a very low amount of heat in order to not further extract the bitter parts of the coffee, so be patient and don’t turn the heat up. Check the warmth of your coffee periodically, and remove from heat as soon as it’s warm enough.

Does Reheating Coffee Change the Caffeine Content?

No. Caffeine is perhaps the most heat-stable component in coffee, meaning that no amount of heating will get rid of it or change the amount of it. 


While there is no harm in microwaving coffee, it’s just a bad experience that nobody should go through.

If you forgot your coffee out for too long, just make a fresh cup instead of having to trouble yourself with finding ways to reheat it. Trust us, you will thank yourself as soon as you take a sip from your freshly brewed coffee.

Have a great day, and enjoy your coffee.