How to Reheat Coffee

It's a Thursday morning in the middle of winter, and you're just dying to get through the week. You make your cup of coffee, but then your phone rings, and you have to leave straight away. You quickly get dressed and go out without having the time to enjoy your coffee. What can you do with it now, though? Can you reheat it? Yes, you can. Keep reading to find the best way to do it.


The Different Approaches to Reheating Coffee

You’ve probably been in the position where you make a cup of coffee, but instead of sitting down to enjoy it, you have to leave it. Unfortunately, when you come back to your coffee, it's gone cold and lost its charm. What can you do then? Is reheating coffee a good idea?

The short answer is yes; you can reheat coffee. You need to watch out not to use a cup of coffee that's been sitting around for too long. By too long, we mean more than four-five hours as that's when coffee starts to go bad. If you are counting on having that cup of coffee that you made in the morning after you've come back from work, we wouldn't recommend it as it's not very safe.

You should know that these four to five hours are valid for coffee with no additives like milk or cream. If you add milk or cream to your coffee, you must leave it in the fridge before reheating it. While your coffee can last a more or less long time, milk and cream can't. If you leave them out in the heat, they will go bad, and not only will the taste of your coffee be terrible, but it will also make it unsafe to drink.

The best way to make sure you can reheat your coffee after a full day is to leave it in the fridge and preferably covered. This way, you will preserve more of your coffee's flavor right after brewing it, and it will be more delicious after reheating.

After making sure your coffee hasn't gone bad and you've kept it in the fridge, there are a few ways to reheat it. Of course, according to coffee enthusiasts, you're better off making a fresh batch of coffee, but if you still insist on heating your old one, here’s how to do it. 

The best ways to do it are on the stove and in the microwave. Even though reheating your coffee this way is easy, you should still consider a few things, and we'll look into them in the next section. 

Another way that might work if you quickly want to heat your cup of coffee from the morning is in a convection oven. We wouldn't recommend that, though, as it will make your cup hot and eventually heat your coffee. But you will need to be careful. Also, if you decide to do that after putting your coffee in the oven, you will need to use hand protection not to hurt yourself.

How to Reheat Coffee on the Stove?

Reheating coffee on the stove is the best way to enjoy your coffee a few hours after you've made it. The biggest downside here is that it takes longer than other methods. 

If you heat your coffee that way, you will preserve more of its aroma. The aroma gives the coffee its bitter-sweet taste, which we all enjoy so much. But if you leave your coffee out for too long, all of that is gone.

The trick to reheating your coffee on the stove is to be patient. You shouldn't crank up the heat and try to get it back to the perfect temperature as quickly as possible, as this way, you risk burning the coffee, making it bitter and undrinkable. 

If you're using a gas stove, you should turn it up to around 20% power, and if it's an electric one, up to 30-40%, depending on the stove. This way, you will gradually reheat your coffee to the perfect temperature. You should remove the coffee from the stove before bubbles begin to rise to the surface, though. If they do, this will mean that your coffee is starting to boil and will most probably burn.

Reheating Coffee in the Microwave

Reheating coffee in the microwave is the fastest way to ensure it's at the best temperature. However, the high price you will have to pay is the taste of your coffee will be affected. Nevertheless, it might be a good option if you just want quick caffeine shot and don't care that much about the taste. However, a tip for preserving the taste is to set your microwave to medium power when reheating your coffee.

There is no exact answer when it comes to how long you should heat your coffee in the microwave. However, the rule that most coffee aficionados who have tried reheating their brew recommend following is one minute. After it passes, you should check your coffee every 30 seconds until it reaches the correct temperature.

Something important you should keep in mind here is that you shouldn't use a cup that has any sort of metal on it. That includes metallic painting as it will retain heat just as well. If you're unsure, you should be careful, and just in case, you can use a towel or a thick cloth to take your cup out of the microwave.

Can You Reheat Your Coffee in the Coffee Maker?

While you can undoubtedly reheat your coffee in the coffee maker, we recommend against it. Most coffee makers keep your coffee warm because that’s a part of their design, which is fantastic if you've just made coffee, but they're not as good if you want to reheat the coffee you made a few hours earlier.

As a coffee maker (whether it's a Moka pot, French press, or another), it was made to brew coffee and not reheat it; it will simply burn it. So when brewing coffee, it doesn't matter how fast the water and the coffee heat up. It's actually better if the whole process goes through quickly as it won't burn your coffee grind. When we're talking about reheating it, though, it's another story.

If you already have made your coffee and try reheating it in a coffee maker, that will completely ruin its flavor. The bottom layer of the drink will be way too hot and burnt, and the top will still be cold. That's why heating your coffee in a coffee maker is a big no.

What Happens if You Heat up Your Coffee After It's Gone Cold?

You will probably agree with me when I say that there's no better way to start your day than a freshly brewed coffee. But, unfortunately, sometimes there's no way you can enjoy your cup of coffee immediately after you've made it. So let's look into the stages that your coffee will go through after you've finished brewing it and what exactly happens when you heat it after it’s gone cold.

Too Hot 

Once you make your coffee, you shouldn't drink it immediately as it will scald you. Most types of hot brewed coffee are made at a high temperature of around 200 degrees (95°C) Fahrenheit, so you’ll want to wait for it to cool off.

Best Serving Temperature

The best drinking temperature for coffee is between 140 and 160 degrees Fahrenheit (60-70°C). Your brew usually gets to the perfect temperature a few minutes after making it. If it is too hot, it will be difficult to drink and can cause burns, and if it is too cold, it will be difficult to taste the flavors of the coffee beans.

Coffee Starts Losing Its Taste

You should only leave the coffee out for a few minutes before drinking it. If you leave it for longer, it will get too cold, and most of the flavor and aroma will disappear.

Your Coffee Gets Bitter and Acidic

The next step of your coffee's path to oblivion is when it starts getting acidic and bitter. You could easily say that your coffee has gone bad when that happens. What happens is that the oils in the coffee start to decompose and ruin the taste. The longer the coffee stays, the more bitter it'll get and the worse the smell will become.

Espresso Becomes a Sludge

If you leave your coffee out for longer, it will turn into an overly bitter cup of muddy sludge. How long exactly it takes depends on many factors, including the coffee you used, ambient temperature, altitude, and coffee quality.

Does Reheating Make Coffee Taste Bitter?

Reheating your coffee will give it a bitter taste no matter what you do. Although, you can control how bitter it will get when you heat it. 

The increased bitterness comes from the fact that you slightly overbrew the coffee. Like dark roasted beans, the more you brew your coffee, the more bitter it will get. If you prefer a more bitter cup of coffee, then go ahead and reheat it.

An important thing to remember is that no matter what way to reheat coffee you pick, you shouldn't burn it. If it's burnt, it's not going to be to anyone's taste.

Where to Keep Brewed Coffee?

Brewed coffee has a shelf life of around four hours at room temperature. Therefore, it's best to keep it in the fridge, as if you've added dairy products to it (cream or milk), it will go bad even faster - as we already mentioned above. 

Another tip that we can give you is to keep your coffee in an airtight container. This way, you can save more of the aroma and after reheating, get a cup of coffee with a better flavor.

Something else that you can do but isn't for everyone is even to freeze your coffee. We recommend doing that if you're not going to drink your coffee any time soon but don't want to throw it away. You can also make iced coffee cubes, which would be great for when you make your fresh batch of coffee and cool it down. They're also perfect for the hot summer days.

Frequently Asked Questions

Does Microwaving Coffee Remove Caffeine?

No, microwaving your coffee won't make it less caffeinated. Caffeine is released into your coffee with brewing, so reheating won't affect its levels. 

While some compounds break apart when you heat coffee for extended periods, caffeine is not among them. If you heat it for too long, it's still going to be sour though.

What's the Ideal Temperature?

The perfect serving temperature for coffee is around 175° to 185°F (80-85°C). That’s when your coffee's aroma has peaked, and if you keep it at that temperature for longer, it'll start losing its taste.

Final Thoughts

While most Italians probably get sick of the thought of reheating coffee, you can still do it and have it taste well. However, you should be careful not to heat it for too long as it'll go bitter and you will completely ruin the aroma. The best way to reheat your coffee is on the stove, but it takes a few more minutes than in the microwave, which on the other hand, is more likely to ruin it.

If you're looking for a way to make strong, delicious coffee at home, you should treat yourself to a Moka pot. Head over to our store to get your high-quality stovetop espresso maker now!