“Can you heat up cold brew coffee?”
Does it sound like a stupid question? Surely cold brew coffee is supposed to be enjoyed cold?
If you’re a true fan of cold brew then you’ll likely understand how different this coffee tastes compared to iced coffee or hot brewed coffee. Cold brew is a unique type of coffee that does a lot more than just cool you down. The subtle flavors and low acidity found in this type of coffee attract many coffee lovers to swear by it.
If you’re fed up with bitter, over-extracted drip coffee then you may want to consider brewing coffee in cold water before heating it up. Cold brew coffee is a gentle, slow extraction process that can be heated up when it’s finished brewing to give a sweet and full-flavoured cup of joe that’s gentle on your stomach.
There are loads of good reasons to switch to cold brew but before we dive right into these let’s first look at what is cold brew coffee so we can really understand this brew method.
What Is Cold Brew Coffee?
The very essence of cold brewed coffee comes down to the brew method used. Instead of using hot water, cold brew is freshly ground coffee beans brewed in cold water for a long period of time. This method gives a slow extraction of the coffee flavors and results in a sweet coffee taste.
Cold Brew vs Iced Coffee what’s the difference?
This dilemma comes up a lot where cold brew and iced coffee are both sold on the menu at a coffee shop. Although they sound like the same drink they are made in a very different manner. Where cold or room temperature water is used to make cold brew, iced coffee is actually brewed hot before it’s cooled and enjoyed over ice.
Why Choose Cold Brew?
You may be wondering at this stage, why choose cold brew over any other brewing method?
There are some clear advantages to choosing a cold brew brewing process over a hot coffee. The first is the taste. Cold-brew has a delicate and sweet flavor profile as the subtle coffee tastes are preserved with this brew method. The next point is that cold brewing makes coffee that is low in acidity, so ideal for sensitive stomachs.
Cold-brew doesn’t require you to have any specialist equipment or a heat source to make your coffee as all you need is coffee, a jar, and a method to strain away the coffee grounds when it has finished steeping.
If you don’t mind waiting a few hours for the initial batch of cold brew to be ready you can store the leftovers in the fridge and then you can have a cup of cold brew ready to go, instantly until it runs out!
How To Make Cold Brew?
Cold-brew is easy to make. To start with, you need coarsely ground beans or whole beans and a coffee grinder. Next, you need some water and a jar to mix these together. I’d recommend using coffee to water at a ratio of around 1:7 but you can up the coffee to a 1:4 ratio if you want very strong cold brew concentrate.
The type of coffee you choose is down to your personal tastes. I love using a dark roast as these coffee beans are lower in acid and the rich, single note flavors really shine through when you brew this coffee cold. However, if you prefer a delicate, lighter roast then you can use these beans instead.
You can add the coffee directly to the water or add them in a metal diffuser, cheesecloth, or coffee bag. Cold brew coffee makers often have a strainer built-in which makes it easy to remove the grounds after. Another great option is you can use a french press as both the container and the mesh filter will strain away the coffee.
It’s best to use a sealed jar if possible as this helps keep the coffee fresh. You can brew the coffee in the fridge or simply at room temperature. Leave the coffee to brew for at least 8 hours but ideally 12-18 hours. Any less than 8 hours and the full flavors won’t diffuse and any more than 24 hours can lead to a bitter, over-extracted cup of coffee.
When the coffee is ready, strain away the grounds and this leaves you with cold brew coffee concentrate. This is a concentrated form of coffee that can be topped up with water, served over ice as is or you can add milk to give a latte-like drink.
How To Heat Up Cold Brew
In the winter months, ice cubes can be the last thing you want to reach for. When a hot cup of coffee is all you’re craving you don’t have to resort to regular coffee. If you love the full flavors of this brewing method, then you may want to consider trying a hot cold brew.
As a tip, I wouldn’t recommend heating the whole batch of cold brew in one go as reheating the coffee repeatedly can affect the taste over time causing it to not last as long. Heat up just enough for your coffee recipe and store the rest in a sealed container in the fridge until you’re ready to use it.
You can heat up cold brew coffee in several ways as long as you’re careful not to burn it. Never boil cold brew, but you can heat it over a low heat on the stovetop until it’s around 200F (93C).
Top Up Cold Brew Concentrate with Hot Water
If you’ve got an electric kettle this is by far the easiest option when it comes to reheating your cold brew, provided that it’s brewed as cold brew concentrate. And this even works with store-bought cold brew.
You simply boil the kettle to just off the boil (around 180F works fine, because you’re not brewing the coffee simply warming it up you don’t need boiling water) and add it to the concentrate like you would if you were making an Americano with espresso.
This makes some of the best coffee because you can adjust it to the strength you want, if you want a very strong coffee you can add less water or if you want to keep it traditional a 3 parts water to 1 part coffee does well.
Add Hot milk To Cold Brew
Another method that some people use is to warm the coffee gently before topping it up with steamed milk to give speciality coffee drinks like a latte or cappuccino.
Because steamed milk is generally not heated as high you need quite a lot of it to get you a proper hot coffee if you’ve just taken your cold brew out of the fridge. Since espresso is usually hot when you make a latte or such like.
So this again works well as a heating method with cold brew concentrate as it’s got a strong enough flavour to keep it punching through the milk.
Reheat on the Stove Top
When we talk about reheating coffee this is generally what we recommend if you’re going to do it. Set your stove to a medium heat and slowly bring the coffee up to your desired drinking temperature.
You want to make sure you don’t overdo it, and remember you’re not brewing coffee you’re just drinking it so you don’t have to heat it all the way up to 190F because you’ll then just have to wait for it to cool back down!
Heating Up Cold Brew In The Microwave
This generally isn’t recommended because it’s all too easy to heat it too fast and end up scalding the coffee and completely ruining the flavor. But where there’s a will, there’s a way…
You can heat up in a microwave but you want to do it in small 10-15 second bursts, stirring in between and maybe not on the highest setting.
I also learned that microwaves can superheat food so the centre of your coffee could get to more than the boiling point at 212F! Which I’m sure you won’t be surprised to hear will ruin your cup of coffee. That’s why you have to take it slow and steady.
Sound like a lot of work? Well making delicious coffee is. If you just want some hot awake juice however go ahead and just bang it in the microwave (but not for too long), it’s safe to do so except you might burn yourself when you drink it!
Will Heating Up Cold Brew Make It More Acidic?
This is a worry a lot of people have, I know many people can’t handle overly acidic coffee, and in fact, that’s why there’s such a huge market for it.
And as we talked about earlier, cold brew generally brews lower acidity coffee compared to hot coffee, there was even a scientific paper that compared the two brewing methods and concluded that generally, hot coffee extracts more acids than cold brew does.
So what will heating cold brew do to the acidity?
Well I’ll tell you, it’s the chemical reactions that are occurring during the process that extract acids out of the coffee beans and into your cup. Once the coffee beans and any coffee fines are no longer present the extraction process stops.
This means that provided your cold brew is properly filtered there will be no more extraction and so it won’t get any more acidic.
This is also why the caffeine content will stay the same when it’s reheated.
Does Hot Cold Brew Coffee Taste Different?
Heating up cold brew does change the flavor, in a similar way to how your hot coffee has different tastes as it cools down.
But it depends on how old the cold brew is and what method you use to heat it up, if you’re doing it on the stove then it will have a more caramelly flavor (generally) but if you’re diluting concentrate then it depends how much water you add.
All this is to say it doesn’t taste worse when it’s heated up, it just tastes different, and if you don’t like the new taste do what everyone else does and fire in some creamer, I’m not judging.
Can You Order a Hot Cold Brew At Starbucks?
Some people prefer the taste of heated up cold brew, and when it’s a totally different brewing process I think that is completely fair.
Your local Starbucks barista however may raise an eyebrow when you try and order it, and I’m not entirely sure how they would go about heating it up but it is definitely something they could do.
What they might not do is heat up nitro cold brew coffee, because the whole point of that is the nitro process that gives it a creamier mouthfeel and a slightly sweeter taste. Because all the nitro would escape when it was heated up so it would be a waste.
If you’ve brought home your cold brew however that can definitely be heated up using any of the methods I’ve talked about here.
Final Thoughts
Cold brew coffee is a unique and rewarding way to brew coffee. It’s really easy to do and doesn’t require much equipment at all. The coffee flavors are beautifully balanced and you end up enjoying coffee like you never have before. The good news is, you don’t have to limit cold brew to the summer months as it can be gently heated once brewed on the stovetop or in a microwave.
I love cold brew coffee and I’m certain you will too, and I’m even confident you’ll soon be enjoying a lovely warm cold brew as weird as that is to say!
