Cold brew coffee has become a big trend in the coffee industry in the last few years. It claims to improve the taste of coffee and has got many coffee enthusiasts very excited. But what exactly is cold brew coffee and what’s the difference between it and regular coffee?

We’ve put together this little guide to help explain everything there is to know about cold brew coffee and offer some delicious recipes and tips to help you get started with cold brew.

What exactly is cold brew coffee?

Not to be confused with iced coffee, cold brew coffee is a type of brewing method that significantly alters the taste of coffee when compared to its usual flavours when brewed with heat. Iced coffee often has connotations of added sweeteners and extravagant toppings, but cold brew coffee couldn’t be further from this. Although it has only just become a popular choice in cafes, it’s a method that has been around for a long time. The Japanese were even using cold brew methods in the 17th Century!

Cold brew coffee tends to be brewed using room temperature water, but can be brewed using colder temperature water too. The science behind cold brew coffee is to avoid higher concentrations of certain flavours and compounds that are released during high temperature brewing. This completely alters the balance of flavours in the final product. Keeping everything controlled, in a blind taste test side-by-side of the hot brew and cold brew of the same coffee, (using the same recipe, same water, same dose, brewing to the exact same strength and using the same filtration etc) it is difficult to even recognise that the two products are made with the same ingredients, let alone the same recipe.

Heat in chemical reactions and processes is often used as a catalyst to speed things up. That is precisely what it does in coffee brewing, allowing water to ‘do its work’ quicker than it would at room temperature or lower. You can look at coffee brewing as a process of dissolving flavours into water, the same process that occurs when you brew with a teabag or loose leaf tea. The process can be done without heat aiding it, but it simply takes much, much longer. The slow version of the process without heat is what is going on with cold brew. A good starting point for anyone keen to try it out is outlined below.

Essentially the basic process can be as simple as making a cafetiere, but without heat. All you do is leave it for 12-18 hours then filter it using your preferred paper coffee filters! We certainly urge any consumer to do this using any glass carafe / Chemex / French Press (cafetiere) that they have at home. It is so simple yet can be a delicious way to try coffee you already have, without the need to buy any more equipment!

Depending on what you want to get out of the coffee you are brewing (for example more or less flavour in a trial and error kind of process), the cold brewing process could end up taking you up to 24 hours to ensure your brewing extracts all the desirable flavour, while hopefully leaving behind unwanted compounds. Usually, cold brewed coffees taste a little less acidic, or at least less sharp than their hot brewed counterpart would. It certainly seems that cold brewing yields a typically less intense, wild flavour than is found with hot brewed coffee.

In cold brew you will typically find lower bitterness too, given that it would take a very long time to extract as many bitter compounds as can easily be drawn from beans when heat is used. It simply takes longer to get to all flavours, which already come out in a ‘queue’ so to speak. Bitter compounds will consequently not be drawn from the coffee used until brewing time extends past your likely ‘desirable’ range (which may of course be subjective according to taste preferences). Some may enjoy a slightly bitter brew, even using the cold brew method. If so, brew longer than those who enjoy either ‘fruitier’ or ‘weaker’ coffee usually. The same goes for hot brews too actually. If you like bitterness, brew for longer. If you don’t, brew for less time than those who prefer more bitterness.

How to Make a Cold Brew Coffee at Home (Step by Step)

The cold brew coffee rewards those who are patient and prepared. The perfect cold brew press coffee will need to be prepared well in advance, usually at least 12 hours. You can either choose to invest in a specific cold brew appliance which are designed specifically for this type of brewing or use a more DIY approach as outlined above, using equipment you’ll almost certainly have in the kitchen already. The appliances can help make the process smoother and can avoid making mess when filtering your brews, but are by no means essential to do it right.

If you don’t want to buy these specific appliances, then you can try it at home using just about any carafe, jug or container. Just be wary of its capacity, which you can obviously measure by weighing how much water it holds. One gram of water equals one millilitre of water, so that’s a nice easy conversion for you!

Personally, I recommend not investing any extra cash and using a large French press or Chemex coffee brewer instead. As long as you already have some paper filters at home, these will be fine. The size of the container will influence how much you can make, and ultimately how strong or weak you can make a recipe using whatever fixed dose.

Step 1 – Grind Your Beans

How long you plan to brew for will influence  how you grind your beans. It also impacts how well you can filter the finished result. Fine grinds are not recommended given that fine particles can pass through filters more easily than coarse particles. We recommend a coarse grind as you might use in a French Press. If in doubt of which grind to use, get in touch with us at North Star about attending a brewing class, where you’ll learn to use this essential variable in coffee brewing without difficulty. Coffee always tastes better using fresh beans, so grind them just before brewing to ensure you have the maximum flavour to work with. Of course, this means buying freshly roasted beans too, and ensuring you store them as advised by the company supplying them.

Step 2 – Steep Coffee Grounds in Cold Water

Before going any further, ensure you have good water for brewing. Use a charcoal filter (Brita jugs work fine, or bamboo charcoal sticks steeped in a glass carafe of tap water) at minimum to get a good starting point. The last thing you want is to wait half a day or more to taste your coffee, only to find it has some sort of chemical taint in it, or simply a flat/heavy/chalky/empty taste to it. Disclaimer over!

So, depending on the purpose of your cold brewing, the ratio of water to coffee should change. A ratio of 1:8 of coffee to water will produce a nice coffee ready to drink after around 24 hours at a coarse grind. Another option is to create a much stronger cold brew (named cold brew concentrate), by using a ratio anywhere from 1 part coffee to 4 parts water, up to around 1 part coffee to 2 parts water. This stronger brew will take much, much longer at a coarse grind setting, but can be quickened by grinding finer. The concentrate is usually then ‘diluted’ with water, milk, ice or a combo of these.

Regardless of the above options, our beginners’ recommendation would be to keep things simple, and to be able to compare it easily to your hot brews of the same coffee. It is very very interesting and highly recommended to do a side by side of your cold brew result next to a hot brew of the same recipe, filtered the same way using all of the same ‘variables’ in a controlled way. For this we say use a ratio of 1 part coffee to 16 parts water (or 60g coffee per litre of water). This is at a coarse grind setting for a cafetiere, and would be brewed for 12-18 hours. Why the range of times? We’re well aware that everybody brews their cafetieres differently, and that’s a story for another day.

Whatever you do, mix the coffee and water together and leave for 12-18 hours at room temperature, or in the fridge for 18-24 hours, (as long as there is no open or smelly stuff in it).

Step 3 – Strain the Coffee

This involves filtering the steeping coffee mixture to remove the coffee particles, leaving only the delicious brewed coffee. The cold brew appliances make this bit easy. If you’re using a cafetiere you can risk using the plunger, though it will as usual leave some particles suspended in the brew. We always recommend paper coffee filters for this step, and pouring slowly, regardless of the filter method you have chosen. If you have one, a sieve with extremely fine mesh would be a good idea.

This part of the process may require some trial and error to find the most suitable filtration method to suit your tastes. Those who like heavy-bodied coffee, for example cafetieres or espressos, will usually prefer metal-filtered cold brew. Those who look for a light-bodied or clean coffee, for example drip coffee / V60 / Chemex / batch brew, will usually enjoy a paper-filtered cold brew. If you normally use an AeroPress, try filtering your cold brew with your usual AeroPress assembly, but without too much pressure by pouring gently and allowing it to flow through of its own accord, if possible. In some instances, using multiple filtering methods could be the most effective way to ensure you have the perfect coffee.

Step 4 – Prepare your Coffee

You should now have your coffee ready to drink. It’s now up to you whether you want to further dilute it with ice/water/milk for example, or even adding it to hot water to enjoy warm. Although cold brew is still associated with a summer drink – enjoyed chilled – adding your cold brewed coffee to hot water means you can get all the benefits from cold brewing and still have it warm, if you’d like. If you brew a cold brew concentrate for example, you could have coffee brewed to your own standards in a large batch, which would be more portable for example if transporting it. You could simply take a bottle of cold brew concentrate around with you and dilute it to whatever strength you’d like at the office for example, hot or cold. This step is completely preference-based. However, we recommend our recipe above to begin with, and comparing it to the hot brew of the same coffee first of all, provided you track your recipes well enough to do so.

Interesting Cold Brew Recipes

We think the cold brew method is often misunderstood and it is actually an incredibly diverse approach to creating coffee. So here are some recipes to try out that use cold brew in different ways:

• Cold brew concentrate – strong ratio (coffee to water ratio of 1:4) brewed at a drip filter setting for 18 hours at room temperature then paper filtered and bottled. Great for use in alcoholic espresso cocktails or for diluting into a longer drink…
• Cold brew espresso martini – ice, 25ml vodka, 35ml coffee liqueur, 35ml cold brew concentrate, shaken together then served in a chilled glass!
• Cold brew latte – cold brew concentrate, stirred into whole milk and ice, to taste.
• Tropical latte – as above but with added sugar and a light, store-bought coconut milk (not a coconut ‘drink’) instead of dairy milk.

Great coffees to try cold brew with

Some of our coffees suit cold brew more than others, but almost all will be delicious via cold brew methods. This is due to our conscious choices to both buy only exceptional speciality grade Arabica coffees, and to roast those great coffees lightly to preserve the develop the inherent flavours of the beans. Recommendations are as follows:

If you like a fruity coffee usually, we recommend either our coffee from Colombia for cold brewing.

If you like a more ‘smooth’ or chocolatey coffee, we recommend our Peruvian coffee, or our coffee from El Salvador for cold brewing.

If you want a balance of high body but also high levels of complexity, go for our Czar Street blend which balances both.

The Benefits of Cold Brew Coffee

Hot brewed coffee will always be a popular method due to the speed at which you can enjoy a delicious coffee. However, cold brew coffee is certainly worth exploring for any coffee enthusiast. If you are buying it, it is also an end product, meaning that the coffee company supplying it are in control of the recipe and the consistency of that recipe. This virtue of bottled or canned cold brew makes it incredibly consistent for use in bars with espresso martinis and the like. Our favourite is Artemis Brew‘s range, as they are local to us in Leeds, using great quality ingredients (some are our coffees), great water and a triple-filtered method for clean cold brew.

As they say, “good things come to those who wait” and if you can wait 12-24 hours for your coffee to brew, then you’re in for a treat by trying cold brew out!