How Long Can Brewed Coffee Sit Out?

We’ve all had day-old coffee. It won’t have any freshness left in it, and you won’t be able to say anything good about it. Even though we know that brewed coffee can go bad, we do consume it against our common sense. If you’ve had that question, then here’s the answer.

How long can brewed coffee sit out? Freshly brewed coffee will retain its flavor and taste good for 30 minutes when left to sit out. If the container is airtight or if the cup is closed, then you can expect the coffee to be flavorsome for 1 to 2 hours. For black coffee, you can let it sit out for 12 to 16 hours without any problem. But for coffee with milk or creamer, 30 to 45 minutes would be pushing it.

How Long is Brewed Coffee Good For?

Your cup of brewed coffee will be in good condition for about 30 minutes at room temperature. This is with the cup left open. If the cup is closed, then you can add another 30 to 45 minutes of good flavor.

Once 30 minutes is gone, you’re not left with spoilt coffee. 30 minutes is the time within which your coffee will retain its best flavors and freshness. After that, you will start noticing the loss of flavor. Some might find your coffee taste bitter.

The rate at which your coffee loses its flavor depends on the quality of the coffee bean used. If your coffee is made from good quality beans, you can expect it to last a little longer than what we said.

Now, with pure black coffee, this equation changes. If we’re talking about pure black coffee, you can leave it outside for even 24 hours. The flavor would have taken a hit, but the ground coffee will not go bad. The earlier your drink your coffee, the more flavorsome it will be.

If you’re dealing with coffee that has milk or creamer in it, then we can say that the coffee will go bad in an hour or two. You can leave them open for more than an hour. This is also applicable for non-dairy creamers made from almond milk, soy milk, and others.

Another factor to consider is the container you use. If your container is airtight, then your coffee will be good for a lot longer than 30 minutes. But if you’re going to leave your hot coffee out in the open, then even 30 minutes might be pushing it.

What Happens When Brewed Coffee Is Left To Sit Out At Room Temperature?

We know the simple answer to what happens to your brewed coffee when it sits out at room temperature for a long time.

It goes bad, right?

But bad can mean different things to different people. For someone who is very picky about his/her coffee flavor, going bad could just be the loss of the freshness. If a beginner coffee enthusiast, going bad is the coffee becoming not drinkable.

Why does this matter? Why there is no standard to keep things the same for all people?

To answer these questions, we need to know what happens to brewed coffee at room temperature at a deeper level.

Oxidation Happens

When coffee reacts with air, oxidation happens.

Air reacts with coffee and oxidizes it thereby reducing the flavor of the compounds inside. The more time you allow the coffee to oxidate, the more flavor you would lose.

To understand this easily, it is the same thing that happens to an apple when you cut it open and leave it on the table.

Oxidation is not necessarily a bad thing. In fact, when you brew coffee, it is the oxidation that lets out all the aroma and flavor from the coffee grounds. But when the oxidation continues even after you’ve brewed the coffee, its flavor will deteriorate quickly and you will end up with tasteless coffee.

Temperature also plays a role in this oxidation process. If your brew is hot, oxidation is quick and you will lose all the goodness faster. This is also the reason why a cold brew retains its freshness and flavor even after a long time.

To prevent this oxidation process, you can try storing your coffee in an airtight container like a mason jar with a tight lid.

During the oxidation process, coffee will also absorb the smell of the surrounding items. So if you have leftover food around your open coffee, you will feel its flavor when you take the next sip. Trust us when we say this isn’t a good thing.

When you feel like too much oxidation has taken place, you can reduce the bitterness and staleness in your coffee by adding a pinch of salt into your cup.

The Oils In Your Coffee Go Rancid

When you leave your coffee open for a long time, the oxidation process results in your coffee oils going rancid.

In simple terms, your coffee develops a not-so-good taste. It won’t be bitter but something that is unpleasant and will punish your palate. The more hours you keep your coffee open, the more chances of this happening.

Thanks to this reaction, free radicals are created in your coffee. Free radicals are not good for your body. Good coffee comes with antioxidant properties that fight against free radicals. When you mistreat your coffee, it becomes the thing it swore to destroy.

Some experts say that it can take up to 4 hours before your coffee oils go rancid, but we’re not sure about that. We think it’s more dependent on the room temperature than the time. The higher the room temperature, the faster your oils will turn rancid.

A simple way to prevent this from happening is to store your coffee in a thermos. If you don’t want a sophisticated (?) solution, then you can simply close your coffee with a coaster to prevent or minimize oxidation.

Will You Lose Your Caffeine?

You won’t.

Yep, leaving your coffee open even for hours won’t affect the caffeine content in your coffee. If you like your coffee only for its caffeine content, then you have nothing to worry about here.

Coffee loses a lot when it is left open, but caffeine is not one of them. The bad news is that you do lose a lot of good things as well. The antioxidant properties deteriorate quickly when left open and this applies to other health benefits too.

Your Coffee Gets Molds and Bacteria

Your coffee will grow mold if you give your coffee enough time in the open. The good news is that this won’t happen on the same day or the next. It usually takes around 4 to 7 days to see something like this.

The growth of bacteria is another reason why you shouldn’t drink old coffee. Not all bacteria are bad, but the ones that develop in your old coffee are definitely not good. They can turn bad-tasting coffee into hazardous coffee, and that’s not a good thing.

If black coffee is your poison of choice, then you don’t have to worry about much here. The protein and carb level in black coffee is low, so it can’t support the growth of bacteria positively. But if you add milk or cream to your coffee, then you should be wary of this issue.

You have a fighter in your cup of coffee that can delay this as much as possible. Yep, we’re talking about the caffeine in your cup of joe. A research article shows that caffeine can hurt the growth of bacteria like E.coli. While this is good news, caffeine can only fort for so long. Always consume your coffee quickly to avoid bacteria buildup.

Another factor that allows this buildup of bacteria and mold is your coffee maker. If you don’t have a coffee maker, this section is not for you. But if you do, read on.

Regular cleaning is paramount for your coffee maker. Failure to do so will allow different species of bacteria to form colonies in your coffee maker. These colonies can fasten the growth of bacteria and will make your coffee go bad sooner than you think.

Pseudomonas is a common bacteria that is found to form colonies in your coffee maker. This bacteria comes with caffeine-killing properties and will affect the amount of caffeine you get in your coffee. If you don’t manage to clean your coffee machine regularly, this bacteria will make your coffee cup stale and less energetic.

Some people will argue that heating can get rid of the bacteria growth in your coffee. It is true to some extent, but reheating your coffee brings up other concerns so the only right way to handle this is by regularly cleaning your coffee machine.

You can clean your coffee machine with a little bit of vinegar or something similar. If you don’t want to use vinegar, here’s how to clean your coffee maker without vinegar (10 alternatives discussed).

Your Milk Goes Bad

If you add milk to your coffee, then this section is for you.

Milk is best stored when the temperature is 40 degrees Fahrenheit and below. When you keep your milk at a temperature between 40 and 140 degrees Fahrenheit, the chances of bacteria growing in them are very good.

Next time when you leave your milk coffee open, take the room temperature into account.

If the room temperature is between 40 and 80 degrees Fahrenheit, your coffee will not hold well for more than 2 hours. If it has crossed 2 hours, you should throw out your cup of coffee.

When the room temperature is between 80 and 140 degrees Fahrenheit, your coffee will be good for more than an hour. It is better to throw your coffee away after your open coffee has been in the open for more than an hour.

So a good practice is to consume your latte within 2 hours after you get it in your hands. If you’re going for an iced latte, 2 hours is fine. But if hot latte is your preference, I would bring the time down to 1 hour at best, just to be safe.

Other Factors That Affect The Shelf Life of Brewed Coffee

The brewing method you prefer can also affect the shelf life of your coffee.

Cold brew is a great way to extend the overall shelf life of your coffee. This is because there is no water used when making the cold brew coffee. The flavor profile will stick with the coffee for a much longer time when kept cold inside a fridge.

When stored inside the fridge, you can use the cold brew concentrate for up to 2 weeks. This is a safe timeline and there won’t be any noticeable deterioration.

But if you keep your cold brew outside at room temperature, then we suggest you discard it after a couple of days. Even this is a significant increase in shelf time when compared to a hot brew method.

If you like to drink your coffee hot, as opposed to iced coffee, then you can heat your cold brew coffee without any issues. If the question inside your mind is, can you heat cold brew coffee, the answer is a solid yes. Click to link to know more about heating your cold brew coffee and drinking it hot.

Another factor that affects the flavor retaining capacity of your coffee is its roast profile.

Experts have found out that dark roasted coffee beans make coffee that will lose its flavor faster when compared to light roasted beans.

You can also use filters while brewing your coffee to preserve its flavor a bit longer. Using a thick coffee filter will filter out most coffee oils and your coffee will have less of them.

This means that oils that could go rancid are no longer present in your coffee. That’s one thing you don’t have to worried about when leaving your coffee on your table.

For example, the coffee brewed with a Chemex filter will stay fresh and flavorsome when compared to the brew made with a French press.

These are only two of the factors that can reduce the shelf life, more like table life, of your coffee. The key is still to keep your coffee closed or keep it in a refrigerator. Leaving your coffee open at room temperature is a recipe for losing its flavor. Over time, you end up with a bad-tasting coffee that could potentially make you sick.

Frequently Asked Questions

Can I drink a day-old Starbucks?

If you had stored your Starbucks coffee in the fridge with the seal intact, then there shouldn’t be any problem drinking it.

But if you are talking about leftover coffee in the fridge, you shouldn’t drink it. If you had left your Starbucks coffee to sit out at room temperature, then there is a good chance that it has gone rancid. It won’t taste well and you can’t drink it.

How long can coffee sit out with milk?

Coffee with milk can be left to sit out for about 30 to 45 minutes maximum. Milk can go bad quickly so if you want to have a fresh cup of coffee with milk or creamer, consume it within 30 minutes for the best results.

The same is true when using non-dairy creamers made from almond milk, soy milk, coconut milk, and other options.

How long can you keep brewed coffee in the fridge?

Keeping your brewed coffee in the fridge is a good way to increase its shelf life. If you’re game, you can even keep your brewed coffee in the fridge for up to 7 days.

But be informed that your coffee will lose all its freshness and will taste bland and dull at the end of 7 days. So the earlier you drink your coffee, the nicer it will be to your palate.

How long can a latte sit out before it goes bad?

You can leave your latte to sit out for about 30 minutes to 1 hour at room temperature. More time at room temperature may not spoil the latte, but will surely kill the flavor of the drink. Since milk or creamer of some kind is involved, it is important to consume it at its freshest.

Can drinking day-old coffee make you sick?

If your day-old coffee was inside the fridge for the most part, then there is a good chance that it might still be good. Drinking that coffee might give you the same freshness, but will surely not make you sick.

But if you have left the coffee to sit out for a day at room temperature, then the coffee would have gone rancid. Drinking this coffee might make you sick if it had milk or some other creamer in it. The taste of the coffee will also be pretty bitter and bad.

Is it OK to drink coffee left out overnight?

No, you should not drink a coffee that has been left out overnight. There is a good chance that the coffee may have gone rancid or could give out a bad smell. If this is the case, then you must not take it.

On the other hand, if you had left out black coffee, then you can consume it as black coffee has a much better shelf life and will not go rancid at least for a couple of days.