Iced coffee is a summertime favorite for a considerable amount of people. This summer delight, however, often takes time to prepare, and it is the preference of many to prepare a glass or two beforehand and leave it for the morning.
Iced coffee does perfectly fine in the fridge overnight. If you don’t leave it for more than a few days, it won’t grow harmful bacteria and will still taste just as good as the first day. There are many other coffees, such as cold brew, that are even meant to be stored in the fridge.
In this article, we’ll cover the difference between iced coffee and cold brewed coffee and what effect time sitting in the fridge has on this tasty treat. Let’s jump in!
What Happens to Iced Coffee When You Leave It in the Fridge?
The answer to this question depends on a few factors – for example, how long after brewing was the coffee placed in the fridge? Iced coffee is made from hot brewed coffee that has been cooled down. This wouldn’t be an issue if it wasn’t for the fact that brewed coffee sometimes becomes stale if it isn’t either drunk or refrigerated right away.
Here’s an interesting YouTube video with more information about how long brewed coffee lasts before going stale:
If you’ve placed the coffee in the fridge straight away after brewing, you can expect that coffee will remain as fresh as possible in the fridge overnight. You will, however, notice that the coffee flavor may be affected after a night in the fridge.
How Does a Night in the Fridge Affect Coffee Flavor?
You may notice a few things when you put iced coffee in the fridge overnight.
The first thing you might become aware of is that the coffee is weaker than before. As its name suggests, iced coffee is typically made by placing ice in hot coffee. Throughout the night, in the fridge, the ice melts and increases the water volume in the coffee. By morning, all the ice has melted, and the coffee has often been significantly diluted.
This effect can be managed by not placing ice in your coffee ahead of time. Instead, place a hot cup of coffee in the fridge and allow it to cool over time. You can always add ice when you’re ready to drink it in the morning.
Sitting in the fridge overnight also causes the bitterness of the coffee to stand out more. This happens because of the coffee’s oxidation process throughout the night.
To help contain the bitter notes, you can seal the coffee in an airtight container. This will allow the coffee to maintain its original flavors without absorbing odors or tastes from other foods in the fridge. Keeping the coffee properly sealed also has the benefit of protecting the coffee from bacteria.
Does Keeping Iced Coffee in the Fridge Make It Go Bad?
As with anything, enjoying iced coffee straight after preparing it will taste the best. However, this doesn’t mean the coffee goes bad while being kept in the fridge. If the coffee has been properly prepared and stored immediately, it should still taste relatively fresh.
Coffee is more likely to go wrong if left in an open container in the fridge. Open containers are a breeding ground for all sorts of bacteria – good and bad. Coffee also acts as an odor absorber. This is especially true before it’s been brewed, but it still retains some of those qualities after brewing.
As stated before, however, many of these issues can be easily prevented by storing the coffee in an airtight container. A mason jar with a lid is an excellent option for this. As an added benefit, they’re also relatively inexpensive.
You may experience the coffee becoming a little stale if you leave it in the fridge for more than one night, but even after a few days, it should still be decent enough to drink, especially if it’s in an airtight container.
Does Adding Milk to Coffee Make It Last Longer?
Interestingly enough, adding a bit of milk to your iced coffee can increase the time you can leave it in the fridge without it starting to go bad. However, the effect is minuscule, only increasing the time by a few hours.
You can extend this out a bit by adding non-dairy milk to your iced coffee.
Overall, iced coffee with milk can be expected to last between three and five days. Be aware, however, that dairy often opens the doorway for more harmful bacteria.
Iced Coffee Versus Cold Brew
I mentioned in the introduction that some coffees are made to be stored in the fridge. Cold brew coffees do significantly better regarding how long they last in the fridge – typically lasting about two weeks.
The reason for this has to do with how the coffee is brewed. Cold brew coffee is brewed over time, and the process begins with cold water rather than hot. It usually takes about forty-eight hours before the cold brew is even ready to drink. In contrast, hot coffee is typically ready to drink in less than five minutes.
You can generally expect cold brew to be fresh for about forty-eight hours, become somewhat stale after about three days, and begin to taste very stale on day seven. It becomes almost undrinkable at around two weeks and begins to mold about a month in.
On the other hand, hot coffee will be fresh for the first hour or two, becomes stale after about three hours, and begins to taste very stale after sitting out for about five hours. After only a few days, the coffee often grows mold and isn’t very tasty to drink long before.
The life of hot coffee can be extended by putting it in the fridge, so don’t be discouraged from doing so. It just won’t last quite as long as coffee made in the fridge.
How You Can Make Your Overnight Iced Coffee Taste the Best
If you want your iced coffee to be top of the line, you can do a few things to ensure that it has the best flavor possible and maintains the highest degree of freshness possible.
You’ll first want to ensure that you’re not brewing too much coffee at a time. Since iced coffee doesn’t last very long, even in the fridge, it’s essential to make small batches that can be consumed the next day after preparing.
You’ll also want to brew your coffee a little bit stronger than you usually would for hot coffee. Typically, you’ll be adding ice to the coffee even after it sits in the fridge, and ice is excellent at diluting things. If you don’t make your hot brew stronger, you’ll likely end up with coffee that just isn’t meeting your caffeine needs, and no one wants that!
The third thing you’ll want to make sure of is that you’re storing the coffee in an airtight container if possible. No container is completely airtight, but a simple mason jar will do the trick here. The reason for this is that it helps to prevent oxidation.
Oxidation is basically just the coffee absorbing extra oxygen. The problem is that oxidation provides an opportunity for more bacteria to grow. You’d be surprised just how much bacteria is in your fridge, and they migrate straight to open containers. Closed containers do a much better job of limiting bacteria growth.
Drink the coffee first thing the following day, and add in cream, sugar, and ice just before consumption. While adding milk can slightly extend the freshness factor, it’s best to avoid doing this. Milk, especially dairy milk, can sometimes form a layer on top of the coffee. This is because the fats in the milk are separating. The result is that your coffee tastes kind of funky!
Dangers of Leaving Iced Coffee in the Fridge
Unless you’re leaving iced coffee in the fridge without many other foods that have gone bad or leaving it in for more than a couple of days, there’s no real danger. The coffee will stay fresh, especially if it’s only left overnight.
However, I would be concerned about leaving it if you haven’t cleaned your fridge in a while. As mentioned, coffee is an absorber, and it can absorb the foul odors and flavors from foods that have gone rancid in your fridge. Many people have quickly stuffed a cup of coffee in the fridge only to return the next day to coffee that tastes rancid.
Final Thoughts
Putting iced coffee in the fridge overnight is perfectly safe to do. It doesn’t have a significant effect on flavor, nor does it produce any harmful effects on the body.
As a reminder, if you want your coffee to taste the best, don’t add ice ahead of time, and be sure to allow it to sit in an air-locked container.
If you’re an ice coffee drinker, I hope this article has paved the way for a better-caffeinated experience!