Can You Reheat Day-Old Coffee?

For some, coffee is a daily ritual that demands total concentration. However, life happens, and distractions can often get in the way of a refreshing coffee break. This begs the question: Can you reheat coffee the next day? If you’re contemplating reheating your cup of Joe, you’ve got to check out the pointers in this post. Below, we’ll go over everything you should know before reheating day-old coffee.

Although you can reheat coffee that's a day old, don't expect it to taste as good as before. When coffee is exposed to oxygen, its delicate flavor compounds quickly degrade. You will need to put coffee in an airtight container in the fridge to preserve its flavor.

Typically, coffee is best savored immediately after brewing. Ideally, you should try to keep your coffee warm for as long as possible. However, if you're going to reheat your coffee, you should review the tips below.

Is It Okay To Reheat Day Old Coffee?

You can reheat day-old coffee that you left in the fridge, but you probably won’t want to. Day-old coffee has a reputation for being extremely bitter and unpleasant after reheating.

The moment your coffee’s phenolic compounds come in contact with oxygen, you don’t have much time to savor their flavors. Most coffee experts claim a cup of coffee will lose most of its delicious aromatics within just 30 minutes.

To learn more about how long it takes for coffee to taste disgusting, check out this video:

Is Day-Old Coffee Safe To Drink?

Day-old coffee usually isn’t unsafe, but it’s unpalatable. We say “usually” because the safety of your coffee depends on how you store it.

If you place your coffee in the fridge in an airtight container, most nutritionists say it should be safe for about three days. However, you shouldn’t reheat coffee that has been sitting at room temperature for a day.

First off, countertop coffee will taste abysmal after just a few hours. On top of that, it’s easier for harmful microbes to form in day-old coffee left at room temperatures: especially if it has milk in it.

Please always store coffee you intend to heat the next day in an airtight container and put it in your fridge ASAP. This strategy will ensure your coffee is safe to reheat and drink one or two days later.

See this container on Amazon.

If you use a Keurig machine to make coffee, you may be wondering whether those coffee pods ever go bad. To find out, read our post, “Does Keurig Coffee Expire?”

Is It Okay To Reheat Day-Old Coffee You Left At Room Temperature?

You shouldn’t reheat coffee that you’ve left at room temperature for a day. After about three hours, you probably shouldn’t reheat the coffee sitting on the counter.

Coffee at room temperature will lose its complex flavor profile within a relatively short time frame. After a few hours, most coffee drinkers note their beverage has an extremely bitter taste.

Also, there’s a greater risk for spoilage if you keep your coffee at room temperature versus in a fridge. This is especially true if you add a lot of milk or heavy cream to your coffee.

To learn more about how long coffee tastes fresh, please watch this video:

Can You Refrigerate Coffee?

You can put coffee in the refrigerator. It’s better to put coffee you don’t intend to drink for a day in the fridge rather than leave it at room temperature.

Optimally, you should put your refrigerated coffee in an airtight container to avoid contact with the air. While the cold temperature of your fridge will slow the spoilage process, keeping your coffee well-sealed adds an extra layer of protection.

How Long Does Coffee Last In The Refrigerator?

Keeping your coffee in an airtight container in the fridge should be good for three days. Some people also don’t have problems reheating coffee left in the refrigerator for four days.

The longer you let your cup of coffee sit in the fridge, the more bitter it will become. However, an airtight container will help slow the oxidation process, so leaving it in an unsealed mug won't be as bad.

Everyone has a different tolerance for bitter coffee, so you may find it’s OK to push it to the fourth day. However, some people find reheated day-old coffee tastes disgusting. It all depends on your taste preferences.

If it’s your first time testing reheated coffee from the fridge, take a small sip first to assess its taste!

Can You Freeze Brewed Coffee?

While freezing brewed coffee will technically make it “last longer,” you probably won’t want to drink it again. The thawing and reheating process destroys so many nuanced flavor compounds, and the resultant coffee will taste lackluster.

However, some crafty coffee fans enjoy pouring leftover coffee into ice trays to make literal “iced coffee.” To learn more about this unique “kitchen hack,” be sure to watch this video:

Does Day-Old Coffee Taste Good?

Most people don’t enjoy the taste of day-old coffee. Even coffee drinkers that are more interested in caffeine than flavor have a tough time chugging coffee that’s been sitting for over three hours.

That being said, everyone has a different tolerance for bitter notes. What tastes unpalatable to one person may be OK for you.

Also, how you store your coffee will play a massive role in how it tastes after 24 hours. If you put your coffee in the fridge in an airtight container, it will “decay” slower than if you leave it on a coffee table.

Bottom line: Most people don’t like the taste of day-old coffee, but you could make it taste “alright” for longer if you store it properly in the fridge.

Does Day Old Coffee Lose Caffeine After One Day?

Caffeine addicts don’t have to worry about day-old coffee losing its “kick.” Unlike the more delicate flavor compounds, caffeine doesn’t disappear after one day.

Interestingly, caffeine is a remarkably stable molecule. Whether you keep your coffee on a table or put it in the fridge, its total caffeine percentage won’t significantly decline after a day.

If you’d like to learn how much caffeine is in an average cup of coffee, please read our previous post, “How Strong Is Keurig Coffee?”

How Do You Reheat Day-Old Coffee?

There are two major ways to reheat coffee: Microwave it or heat it on the stovetop. Most coffee drinkers claim reheating slowly on the stovetop makes the coffee taste better.

Put your heater on low and bring your pot of coffee to just below a boil before drinking it. However, please keep in mind no data shows stovetop coffee is “better” than microwaved coffee.

A coffee expert on YouTube recently discovered that pulsing coffee in the microwave in 10 - 20 second increments produced a better result than reheating on the stove.

Check out this video for more details:

Honestly, no reheating method will bring back the scent and flavor of fresh-brewed coffee. However, if you’re in a pinch, you should try microwaving and heating on low on your stovetop.

Please make a note of which method you feel produced a tastier result.

How Do I Make Coffee Last Longer?

Rather than reheating a cup of coffee, it’s far better to keep your coffee warm for as long as possible. Thankfully, there’s a simple way to achieve this goal: Put your coffee in a thermos mug.

Thermos cups and canisters are more common nowadays, and they do a great job of maintaining your coffee’s temp for a longer time. Plus, since thermos containers have a lid, they’ll help keep out oxygen molecules in between each sip.

Check out this thermos mug on Amazon.

Want to Reheat a Cup of Joe? Give it a Go!

For coffee purists, reheating a cup of java may seem like a sacrilege. However, if the bitter flavors don’t bother you, it’s safe to reheat a day-old coffee that you’ve kept in the fridge.

Sure, the taste of day-old coffee will never be as good as a freshly-brewed cup. However, if you keep your coffee in the fridge in an airtight container, it may taste decent for about three or four days.

Of course, how you respond to your reheated coffee will largely depend on your taste preferences. If you’re super particular about your coffee’s aromatics, it’s probably best to brew a new pot.