Last Updated on June 27, 2023 by Barry Gray
I admit that I’m not the biggest fan of my coffee going cold. It just loses something when the temperature drops, and it doesn’t tempt my tastebuds as much as the hot stuff. But I also don’t want to throw away coffee if I’ve been distracted and not finished. So, how do you reheat it safely, and can you put it in the microwave?
You can safely reheat coffee in the microwave but don’t treat it the same as reheating anything else. You must do so at a lower power setting or run the risk of burning the coffee and destroying the flavor. At that point, there’s a good chance you will no longer enjoy your coffee in the same manner as you were before it got cold.
This is something I’ve done countless times. Still, I admit I was initially guilty of throwing the mug in the microwave and blasting it on full power.
At first, I couldn’t figure out why my coffee tasted as bad as it was when I reheated it. I’m not saying it was horrific, but there was a noticeable change compared to earlier.
So, I had to explore and experiment to get to the bottom and understand where I was going wrong.
After all, so many of us will reheat our coffee to continue enjoying it, so it’s important to get this sorted to help you know how to successfully reheat your coffee.
Is Using the Microwave the Best Way to Reheat Coffee?
I do see using the microwave as the best way to reheat coffee, and I say this because of a couple of reasons.
First, there is the convenience.
It just comes across as so easy to do by simply throwing the mug of coffee in the microwave, hit a few buttons, and a matter of seconds later, it’s all warm and ready to drink.
That also feeds into another reason, which is the speed.
You could go ahead and reheat your coffee on your cooker and in a pot, but do you really want to do that? I feel it takes too long to use that method, and you can cut the time by a considerable amount just by using the microwave.
There are no other ways to heat your coffee, so I would never look past the microwave, even though you need to know how to use it correctly.
Will Reheating Your Coffee in the Microwave Ruin Your Coffee?
I’ve already hinted that a microwave can ruin your coffee when reheating it, but that will only happen if you fail to reheat it correctly.
The problem people have, and I made this same mistake, is that people treat reheating coffee the same way as any other food they throw in the microwave. We are used to blasting whatever is in the microwave on full power, but that’s the problem.
I know the first time I started playing around with the microwave I blasted my coffee for longer than required, and also at full power. I couldn’t believe the same coffee came out of my microwave.
Actually, I had to throw it away, and I hate doing that with any coffee, so you know it tasted terrible.
So what happens?
Coffee is way more delicate than you think, even when it comes to reheating your drink. If you blast it with full power, it becomes possible to effectively burn your coffee, which will change the flavor.
But I need to throw in some science to better understand what’s going on.
The Science of Reheated Coffee
I’m not a big science fan but stay with me for the next few minutes as this explains what happens when you reheat your coffee.
When you make coffee for the first time, the heat in the liquid allows the aroma and flavor to burst out of the ground coffee. When the coffee cools, those aromas and flavors tail off quite quickly.
But if you thought simply reheating the coffee again would make those aromas and flavors burst back into life – you would be wrong.
Instead, reheating at full power will mean you overheat the coffee.
This doesn’t lead to even more flavor but rather the production of too much quinic acid and caffeic acid.
The result? You get coffee that will tend to be overly bitter in taste, and while you may prefer bitter coffee, I think you will find it goes over the top.
So, I think you will be sitting there wondering how you reheat coffee in the microwave without destroying it in the process. Let me take you through it.
How to Correctly Reheat Coffee in the Microwave
I’ve already given you some hints about where you are probably going wrong with reheating your coffee in the microwave. Too much power and blasting it for too long are the two cardinal sins of reheating coffee in the microwave.
But through a lot of trial and error, I’ve hit upon the perfect solution to allow you to get some heat back in your coffee and to do so without ruining the flavor too much.
Use a Rotating Plate
The first thing I want to mention is you do need to use the rotating plate in your microwave. This gives the best possible chance of your coffee being reheated evenly.
If you keep your coffee standing still when reheating, there will be hot and cold spots throughout your coffee. This may not be something you notice when drinking, but it profoundly impacts your taste experience.
This is just something that happens with a microwave. But a rotating plate does help to solve the problem.
Also, I recommend stirring your coffee after reheating. It does help distribute the heat and should help balance out the flavor.
Use a Lower Power Setting
I’ve already told you not to reheat your coffee on full power, but what setting should it be on?
I’ve tried reheating different coffee at various settings with my microwave, and one thing I would stress is you should not simply turn the power down by one level.
That’s not enough to stop you from potentially overheating your coffee and burning it.
Instead, slow and steady heating is the best approach. You gradually raise the temperature of your coffee and don’t simply shock it by throwing a lot of heat back into the coffee.
I’ve heard of people turning down the power setting by a couple of levels, but I feel that’s the maximum. Instead, I turn it down three or even four levels for reheating my coffee.
I know it means it takes a bit longer. Still, I’ve discovered that this setting manages to reduce the degree of bitterness that tends to occur anyway.
How Long Does it Take to Reheat Coffee in the Microwave?
As with any time you reheat something in your microwave, the quantity makes a difference in the length of time it takes to get things back up to some sort of pleasant temperature.
So, I’m going to suggest you have half of your coffee left and want to reheat it.
I feel that’s a reasonable amount of coffee to be left and needing to be reheated because most people won’t have a full cup that they managed to forget about.
With half a cup, it will take 30 to 45 seconds for your coffee to be up to a reasonable temperature.
People make the mistake of thinking they need to get things piping hot again to be enjoyable, but that’s not true. Actually, you increase the chances of ruining your coffee if you go ahead and warm it up to that extent.
But what if you feel your coffee is stone cold after 45 seconds? I know it’s tempting to go and blast it for another 45 seconds, but that’s not advisable.
Instead, I would blast it for 10 seconds at a time. Also, stir it after those 10 seconds and check.
One thing I learned when doing this was that your coffee can move from too cold to too hot and be ruined in seconds.
Can You Reheat Coffee That Contains Milk and Sugar?
This was an interesting question because I’m aware milk, or even creamer, can considerably change things when it comes to coffee. That also means you should take this into consideration when reheating your coffee in the microwave.
The problem with milk is it gives you a second thing that you can unfortunately burn.
There’s also the risk of overheating the milk to such an extent that it burns your mouth when you take a drink.
What I’ve discovered here is to cut those time intervals down to 20 seconds and then check. It always seems as if coffee with milk heats up faster, and that also means it’s easier to spoil your coffee by overheating.
My Recap on Heating Coffee in the Microwave
I’ve shown that reheating coffee in the microwave is possible. Also, it’s the best approach out there compared to trying to warm it on your cooker.
Yet, there are several key points I want you to remember that will help you get some perfectly reheated coffee without running into too many problems.
- You can reheat coffee in the microwave
- Your coffee will taste more bitter no matter what you do
- Use a rotating plate to ensure it heats more evenly
- Stir your coffee after heating
- Lower the power setting as full power will burn your coffee
- Reheat for up to 45 seconds and test
- If still cold, run it in 20-second intervals and taste
- If containing milk, heat for 20 seconds at a time
You no longer have to worry about throwing away cold coffee. But don’t run your microwave for longer than those 45 seconds. It’s very easy to burn your coffee, at which point you need to throw it away, and that is something nobody wants to do.
If your coffee has cooled down, simply reheat your mug in the microwave. However, do so at a lower power setting to preserve as much of the flavor and aroma as possible.
Too high a power setting will mean you burn the coffee, and that’s going to destroy your enjoyment, and nobody wants that to happen.