What is cold brew coffee?

On a hot summers day there’s nothing quite like a nice, cold … coffee?

Although Cold Brew Coffee isn’t exactly a new innovation, in the last few years interest in the drink has really taken off, especially in North America, where they even have a National Cold Brew day*! Cold Brew Coffee is not quite as popular here in the UK, yet …however, it has certainly been getting a lot of attention recently; so what exactly is Cold Brew, and what makes it different?

First of all, it’s important to recognise that Cold Brew is not the same as ‘iced coffee’ or a blended cold coffee drink; to make a Cold Brew, we’re not just adding ice to the coffee! Cold Brew Coffee involves a different extraction method, this significantly alters the taste of the coffee when compared to the flavours we would get if we brewed the same coffee with heat.

Preparing a Cold Brew is a much slower process than brewing a normal coffee because we don’t have the heat to help us move things along as quickly. Heat is often applied to make a process or chemical reaction happen faster – we use it as a catalyst to speed things up. This is exactly what happens during coffee brewing, adding some heat allows the water to dissolve the coffee quicker than it would at cooler temperatures – the increase in temperature affects the solubility. If we think of coffee brewing as dissolving flavours into water, it can be done without heat – it will just take much longer. This slower extraction of flavour is what’s going on in a Cold Brew process.

How's cold brew made?

Essentially we are using cold filtered water, coarsely ground coffee, and a much longer steep time to prepare the Cold Brew. Once the grinds have been left for 12-18 hours, you can just filter and serve. It’s actually a really simple way of preparing coffee! While there are specific products designed for Cold Brew preparation, here are some simple steps to follow that don’t require any fancy kit.

First of all you’ll need a container to brew the coffee in, something like a large cafetiere/french press will be ideal.

You’ll also need good quality coffee, some filter papers, good quality water and some preparation time.

All set? Here’s how to prepare your Cold Brew:

Grind up your beans!

You need a coarse grind – something like you would use for french press

For your brew ratio we recommend between 60 and 70 grams of ground coffee per litre.

Add the grinds to your French Press.

Using cold filtered water, make sure the coffee is fully saturated.

As with all brew methods, making sure you use good quality water is really important. Either use a charcoal filter (e.g. a Brita jug) or purchase some bottled water. For best results use bottled water with relatively high magnesium to low bicarbonate levels. You can buy 5 litres of something suitable for just over £1; e.g. Waitrose Essential, Tesco Ashbeck or Volvic. Using a poor quality water can result in a flat/heavy/chalky/empty tasting beverage.

Put the plunger to one side for later and place the jug in the fridge for twelve to eighteen hours. Make sure you cover your French Press to avoid absorbing any other aromas.

Filter the Brew

You’re nearly there. Now, you can plunge the French Press and serve (just as you would normally would) but for best results you should now filter the brew using paper coffee filters. You can do this through your V60 or Chemex for example.

Serve and enjoy!!

The result is a very clean bright cup of Cold Brew coffee. You’ll find your cold brew tastes less acidic or less sharp, and will seem sweeter because of this.

Using cold water as opposed to hot makes the extraction process much slower and actually more selective. The flavour of the coffee is extracted, but some of the bitter compounds are left behind. In our experience making Cold Brews like this means they can last for up to two weeks in the fridge – not that they ever do!!

Some coffees to try as cold brew:

Some coffees can suit cold brew more than others, as a starting point, try some of these:

If you like a fruity coffee, we recommend our Kenyan or Burundi coffees

If you like a more ‘smooth’ or chocolatey coffee that still has some pleasing acidity, we recommend our Tanzania Tweega.

Let us know how you get on!