We're all guilty of letting our coffee sit for too long. When it gets cold, we usually toss it and make another cup. Yet have you ever wondered whether does coffee go bad? Have you thought maybe you could warm it up and drink it anyway? Here's the truth: I've always wanted to know if I could get by with reheating my coffee. So one day I did warm it back up, and when I added a little cream, it took on a greyish color. Still, I was determined to drink it because I was out of coffee and needed my fix.
Does Coffee Go Bad? Is Bitter Bad?
I'm here to tell you that, though coffee is one of my favorite beverages, reheating it was the wrong move, period. Lesson learned; I'll never do that again. In fact, it tasted so bitter that it made my stomach queasy. Then I got a little worried thinking, does coffee go bad? Maybe I made a huge mistake. So I decided to do some research, and here's what I found.
Taste is complicated
Bitter isn't necessarily bad when it comes to coffee. Of course, when all we taste is the bite, our coffee is ruined. Yet one of the compounds that cause bitterness is also one of the reasons we love coffee so much. As it turns out, caffeine not only wakes us up; it contributes to coffee's flavor. Thus, the higher the caffeine content, the more bitter the coffee tastes. Here's the thing:
Chemically speaking: Does coffee go bad?
Studies show that our sense of taste is there to protect us from potential danger; think of our tastebuds as nature's built-in poison control system. Generally, the more bitter the taste, the more toxic the substance. So caffeine's bitter flavor should keep us from wanting to drink it; thankfully, caffeine breaks that rule, at least in humans. Still, science doesn't fully understand the workings of caffeine on the body and brain. Experts know that it also has a component which inhibits the reaction that causes our aversion to toxic bitter compounds. This inhibitor is why we can like the taste of caffeinated beverages. It's also an indicator that caffeine isn't poison. Although as any coffee drinker knows, there's a limit to a good thing.
Reheating is a matter of taste
As if that's not enough; heat, light, oxygen, and even cream and sugar disrupt coffee's chemical balance and our tastebuds react to those changes as well. However, there's not just one answer to why coffee tastes terrible when it's reheated. The aroma, and the sight of what we're consuming also play a part in how we taste things. So when the reheated coffee looks and smells different, it puts our brain on alert.
It's all in your mind
Finally, how all this information moves from our senses to our intellect is as different as an individual's brain chemistry; which explains why some people can drink reheated coffee and never ask, does coffee go bad? Simply put, that reheated coffee from this morning isn't going to send you to the hospital. However, it does taste bad enough to some of us to keep us from drinking an aged cup of joe. Now, that doesn't mean that coffee never goes bad. If you want to drink the rest of that pot tomorrow, you should put it in the refrigerator. Pro tip: Pour leftover coffee into an ice cube tray and make coffee ice cubes. Here's why:
Does Coffee Go Bad? It's All in the Bean
In addition to caffeine, coffee has over 1000 other compounds, including lipids, carbohydrates, and fibers. What's more, 30 percent of these ingredients are water-soluble, which means they dissolve in water. So it's not just caffeine that's flavoring our coffee, it a combination of all the other solubles as well. And this makes all the difference; lipids get rancid, and carbs become stale. Not to mention, some of those solubles can mold, especially if you're saving coffee that has cream added. Although, if you refrigerate the coffee, you can extend the length of time it'll take for that to happen. So as long as you drink it within the next couple of days, the coffee won't technically be bad. Fair enough? There's more!
A short-lived life
Coffee begins to oxidize when it comes in contact with air. So essentially, as soon as you open the bag and grind the beans, your coffee is on its way to going bad. Picture an apple when you cut it into slices. It turns color from oxidation; the same thing happens with coffee except we taste the difference. Not only that, but heat also advances the oxidation process, which means the act of brewing the coffee shortens its lifespan. Nevertheless, you can slow down the continuing oxygenation for about 30 minutes after you've made a pot by pouring it in an airtight container. Even so, the point is that coffee is better when you make it by the cup, and drink it within 15 minutes. Now you may be wondering:
Does Coffee Go Bad? Those Beans Have Been There Awhile...
Can a bag of coffee beans go bad? By now, you're probably not surprised that there are a couple of factors to consider. First off, the closer it is to the roast date, the fresher the beans. So if you get your coffee from a local roaster, you can bet those beans are fresher than the bag you buy at the grocery store. Don't worry, though, because the packaging is more important for longevity.
It's all in the package
Many roasting companies do a nitrogen flush when they package their coffee beans. Basically, this process sucks all of the oxygen out of the bag of beans and replaces it with nitrogen. Theoretically, this creates a more stable environment, so no oxygenation can take place until you open the bag.
Long live the bean
Consequently, these beans can last quite a while. It even works for pre-ground coffee. Have you ever bought a bag of coffee that seemed compressed? If so, you can bet they used a nitrogen flush. One thing to remember is that a nitrogen flush isn't considered organic and neither are some of the other packaging techniques roasters use to keep their beans fresh. So those organic beans you love, that come in a biodegradable bag, are going to go bad quicker than other options. The good news is:
Store your beans away from light and moisture
You have some control over how long your bag of beans lasts, even if they're organic. The thing is that as soon as you open the bag, the beans start oxidizing and the packaging is pretty much obsolete anyway. So it's up to you to store the coffee properly if you want to keep it from getting stale. That's why it's worth it to invest in a coffee canister. These handy little storage units have air-tight lids and a one-way valve that pushes out oxygen as well as keeping other environmental influences away from the coffee.
Cold beans, fresh coffee
Additionally, you'll get the best results if you store your coffee in a cool, dry spot. Consequently, the freezer is arguably the best place to store the coffee both before and after you've opened the bag. However, you have to make the coffee as soon as you take it out of the freezer. Don't let your frozen coffee thaw out, and remember that oxygen, heat, and moisture will make those beans go bad. If you're still asking yourself, can coffee go bad? The answer is yes. However, it doesn't smell like sour milk. When coffee goes bad, it smells stale, and you'll notice that the aroma you loved is all but gone.
Fresh Is Best
It's no surprise that fresh is best. Then you never have to question, does coffee go bad. Of course, we don't always have the luxury of brewing our coffee one delicious cup at a time. So we can be aware of things like how we store our coffee and how long we let it sit out to make sure we get as tasty a cup as possible. Also, buying coffee beans instead of grounds certainly helps. Do you have a favorite way to store coffee? Or, maybe you have an idea about reheating or keeping brewed coffee that helps it retain its flavor. We'd love to hear your thoughts and experiences on how to prevent coffee from going bad. Go ahead and leave us a comment or get in touch via our contact form. And, cheers to fresh coffee! Featured Image: Pixabay License, via Christoph