Does coffee go bad sitting out?

In this brief guide, we are going to answer the question “does coffee go bad sitting out” with an in-depth analysis of whether or not coffee goes bad sitting out. Moreover, we are going to discuss whether or not microwaving kills the bacteria and if the water in coffee can spoil.

So without much ado, let’s dive in and figure out more about it.

Does coffee go bad sitting out?

Coffee does go bad after sitting out for a certain time at room temperature. It stays fresh and retains all the goodness of flavors for around 30 minutes. After that its aroma and flavor start to degrade and in just a few hours it develops a rancid and sour taste. Moreover coffee also develops a bitter taste if it is allowed to sit out for a long time.

Brewed coffee

In the case of brewed coffee, iced coffee with milk or creamer, or coffee with added milk it is recommended to store your coffee within 2 hours of brewing it. The bacteria grow at a fast pace between 40 and 140 degrees Fahrenheit and milk is a highly perishable commodity. 

Therefore you should discard a coffee with milk if it was left at room temperature for more than 2 hours as there are chances that bacteria would have already spread over it and would have spoiled it.

Moreover, in the case of the simple iced coffee without added milk or sugar and the plain black coffee, they will not taste the same if you drink them after putting them for more than 4 hours out at room temperature, so you should gulp them down as soon as possible. 

Another thing to consider is that the black coffee should be kept in an airtight thermos or container or else the oxidation reaction would make it stale which continues even after the coffee is brewed. 

You should understand the chemistry of oxidation reactions taking place in the coffee that continues even after the coffee is brewed and they are primarily the ones that are responsible for the development of bitter taste that an old coffee develops.

When the coffee beans come in contact with the air they are oxidized and the same is the case for the black coffee that is left open for some time. This oxidation reaction significantly affects the aroma and the flavor of the coffee with no significant change in the color of the coffee. 

Brewing coffee itself is the oxidation reaction. At the point when the coffee beans come into contact with water, they will start delivering their aromatics, oils, and acids into the water giving you an enriched and flavourful coffee but if the process of oxidation continues even after that it will result in a sharp and bitter flavor and that is not something we want.

Moreover, when you leave your brewed coffee to sit out for a long time, the reaction among hydrogen and oxygen will raise its pH level, making it taste bitter or stale, therefore you should never let your coffee sit for too long in the open.

Coffee beans

Open ground coffee lasts for about a month when stored in a cool, dry, and dark corner of your pantry away from direct sunlight and heat but it begins to lose its peak freshness and flavor after 2 weeks. 

While the unopened sealed ground coffee can last for about 3-5 months in your pantry.

On the other hand, coffee beans can last for up to 6 months if they are properly stored in a cool, dry, and dark corner of your pantry away from direct sunlight and heat. This time can vary depending upon the roasting technique, processing, and storage conditions of the coffee beans.  

Other FAQs about Coffee which you may be interested in.

What is the coffee puck?

How long does coffee last when you drink it?

Will microwaving coffee kill bacteria?

When it comes to microwaving, no doubt that it kills the bacteria present n the surface of the coffee as the microwave heats the item from the outside, but there can be chances that bacteria can still be present in the middle of the coffee as microwaving sometimes leave the cold pockets where bacteria can thrive in the middle of the coffee or any other food item that is heated within the microwave. 

Thus, microwaving a coffee does not guarantee that all the bacteria in the coffee would be killed.

Can the water in coffee spoil?

So when it comes to water, it can stay for a long time even at room temperature but when it comes to water in coffee, as long as no sugar or any other additive is added to it it can stay for some days in the fridge. It is worth mentioning here that the water in coffee tends to pick up flavors, thereby it can pick up the flavor of foods stored nearby that can mess up with its flavor. 

Therefore it is recommended to store your plain black coffee in an air-tight container.

Conclusion

In this brief guide, we answered the question “does coffee go bad sitting out” with an in-depth analysis of whether or not coffee goes bad sitting out. Moreover, we discussed whether or not microwaving kills the bacteria and if the water in coffee can spoil.

Citations

https://www.homegrounds.co/how-long-is-brewed-coffee-good-for/

https://food52.com/blog/13738-is-your-morning-coffee-still-safe-to-drink-in-the-afternoon#:~:text=Just%20as%20coffee%20beans%20go,which%20further%20alters%20the%20taste.