Is It Okay to Drink Day Old Coffee?

Is It Okay to Drink Day Old Coffee?

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If you have left your favorite cappuccino on the counter in your office when you left and found it the morning after, you may be wondering if it is okay to drink day-old coffee? I’ll be exploring the answer to this question and a few others related to drinking day-old coffee.

The short answer to the question is NO, you can’t drink day-old coffee. Not only will your coffee taste bland once it’s reheated in the microwave, but it will also have the early stages of some mold and bacteria growing in it.

Most coffee lovers drink coffee for the unique, crisp taste, which is totally lost in any reheating process. Why then would you want to consider it?

And did you know, if your coffee maker is not clean, bacteria will grow in it? This will have an impact on your next brew of coffee.

Does Day-old Coffee Make You Sick?

It’s highly unlikely you’ll get dangerously ill from a cup of day-old coffee. With that being said, it’s crucial to keep your coffee maker and your coffee pot exceptionally clean. Bacteria not only grows but thrives in and around your coffee maker.

Coffee makers that aren’t cleaned regularly will have residue build-up which in turn will make you sick. Bacteria and mold easily grow in coffee pots and different coffee or espresso machines.

How Can You Tell if Coffee Has Gone Bad?

The simplest way to know if your coffee has gone bad is that it will begin to taste bitter. You might also notice an acrid smell in your coffee as well as from your coffee maker.

When your coffee no longer has that tantalizing aroma that makes you a coffee lover in the first place, it’s definitely time to chuck it out. Once the coffee starts losing its flavor, it’ll also start changing color. The dark, rich color will start turning a lighter shade of brown.

What’s the Turnaround Time to Enjoy Your Coffee?

Ideally, a freshly brewed cup of coffee should be consumed within 30 minutes of being made. As coffee starts cooling, you might be able to get away with a four-hour window as the oils in the coffee beans start deteriorating which will greatly alter the taste.

Does Old Coffee Taste Stronger?

If you’re letting your coffee sit out on purpose to “make it stronger”, you would do better by investing in a stronger roast from the onset. Coffee doesn’t become stronger the longer it sits in your cup. Unlike tea, coffee doesn’t steep after the initial brewing process.

When some of the water evaporates from your cup, you might be left with more concentration of caffeine in your cup, but in essence, that doesn’t make your coffee stronger. Once the coffee is brewed, that’s the peak of the flavor and it’s only downhill from there.

A novice coffee drinker might confuse that bitter taste day-old coffee gets for it becoming stronger. But, it’s actually closer to stale coffee than stronger coffee. As I’ve said before, if it’s strong coffee you’re after, rather opt for the stronger roast from the onset.

Is It Okay to Reheat It?

Genuine coffee lovers will agree that the golden rule of drinking coffee should be to never reheat coffee. This aroma rich drink should be consumed as soon as you make it. Generally speaking, if your coffee gets cold, you should rather brew a fresh cup.

Reheating coffee doesn’t restore the taste. It’s pretty much a one-time deal. If you really need to reheat your coffee, be prepared that it won’t taste as awesome as a fresh cup.

If you’ve added milk to your coffee, then you should definitely not reheat it the next day. Harmful pathogens in milk will multiply quickly and put the coffee drinker at risk of illness.

Can You Reheat It in the Microwave?

If you’re determined to reheat your coffee, because you don’t have the patience to wait for a fresh pot, microwaving it will do the trick. A full mug of coffee usually required about 45 seconds to heat properly.

If you prefer it slightly hotter, you can simply keep heating it at 30-second intervals until it’s hot enough to your personal taste.

I must just warn you though that microwaving coffee breaks down the flavor, and gives coffee a stale taste, leaving you with a drink that’s a bleak shadow of its former self.

Why Does Reheating Old Coffee Taste Bitter?

There is actually a very good reason why reheating day-old coffee tastes bitter. In general, coffee is made up of chlorogenic and quinic acids. Both of these acids have a bitter taste, contributing to the pronounced bitter taste that has made coffee famous.

When coffee is freshly brewed, sweetness and different levels of acidity balance the bitterness, creating the enchanting flavor coffee lovers enjoy so much.

When the coffee starts to cool down, these flavor-rich compounds start breaking down. If reheated, there isn’t a second release of the different elements to create another pop of taste. It literally is a one-time deal.

If you’ve brewed your coffee with a French press, there will also be a few tiny coffee bean particles floating around in your coffee. These particles continue to brew and create a bitter taste while your coffee is reheating.

What About Coffee Makers That Keep Your Coffee Hot All Day?

You might be thinking the solution to this dilemma would be to invest in a coffee maker that keeps the coffee hot all day. But, you’d be wrong. Coffee experts agree that applying continued heat to a brewer still creates that undesirable bitter taste.

This is the primary reason why so many people have stopped using coffee brewers that keep the pots warm on hot plates. Have you ever tasted coffee from an old school diner or a hospital cafeteria? Then you’ll know exactly what I’m referring to!

Coffee shouldn’t be “kept” hot. It should be brewed and once the burst of flavor is released, it should be consumed. Keeping the beans brewing only “overboils” the brew making it more bitter the longer it’s kept hot.

Can You Keep Coffee in the Refrigerator?

As a coffee lover, you might frown upon the idea of tossing out the remainder of your favorite drink, especially if there is a considerable amount left in the pot. Some experts suggest that brewed coffee can be stored in a refrigerator for up to four days.

However, bear in mind you’ll need to reheat it if you want to enjoy it hot. You might consider turning your cold coffee into an iced drink to not lose too much of the flavors. But avoid making it with day-old coffee.

What’s the Best Way to Reheat Refrigerated Coffee?

If you have the time, and access to a stove, experts suggest reheating your coffee on a stove-top, at a low temperature. This will maintain some of the original flavors.

If you know you’re most likely going to refrigerate some of the leftover coffee in your pot, avoid adding sugar and milk. This will prevent bacteria or mold growth.

What Can You Do With Old Coffee?

You might find that there’s still some coffee left in the pot after you’ve had your fair share. It might seem like a waste to just chuck the remainder of the coffee down the sink. Fortunately, there are a few things you can do with your favorite drink that doesn’t involve wasting.

Let’s look at a few of them.

  • Coffee flavored ice-cream: Leftover coffee can make a creamy coffee ice cream.
  • Make a steak marinade: Cold, unsweetened black coffee is a great way to make steak marinade.
  • Add to baked goods: Substituting some of the required liquids with coffee will add a boost of flavor to any baked treat.
  • Add it to your oatmeal: Substitute some of the water with your leftover coffee. This will not only increase the cereal’s flavor but will also give you a double dose of caffeine.

A Final Thought

Given the information in this article, I think it’s safe to say you shouldn’t drink day-old coffee. Not only will your coffee not taste the way you love it, but it will also smell stale. The possibility of bacteria growth increases with each passing hour the coffee stands out.

The best solution would be to drink your coffee when it’s made. Make use of a thermal mug to slow down the cooling down process and enjoy your coffee hotter for longer.

Another way to not waste too much coffee is by sharing. If you’re in the office, let everyone know you’ve just put a fresh pot on. If you’re at home, and a full pot is too much for you to drink, consider using the leftover coffee in the suggested ways above.

Or quite simply, make a new pot and enjoy the aroma and rich taste you fell in love with in the first place!