How to make cold brew at home

Cold brew works on a simple principle: cold water extracts coffee much more slowly than hot water, but given enough time it extracts the same flavors with much less acidity and bitterness. The result is a smooth, sweet, low-acid coffee that's especially good over ice or with milk.

This isn't iced coffee, which is just hot coffee poured over ice. Cold brew is a different drink.

What you need

• A container that holds about 1L (a French press works well; a Mason jar works fine)
• Something to filter through (the French press plunger; cheesecloth; a nut milk bag; a paper filter)
• 100g of coarsely ground coffee
• 800g of cold water
• A fridge
• 12 to 24 hours

The recipe (concentrate)

• Coffee: 100g
• Grind: coarse
• Water: 800g cold
• Steep: 14 to 18 hours in the fridge
• Ratio: 1:8 concentrate

The whole method, in about five minutes of work

1. Grind your coffee coarse, like sea salt. Fine grounds make cold brew muddy and hard to filter.
2. Add the coffee to the container, then pour the cold water in. Stir to fully saturate. Cover.
3. Place in the fridge. 14 to 16 hours is the sweet spot for most coffees. Less and it'll taste weak; more than 24 hours and it can get bitter and tannic.
4. Filter. If using a French press, press the plunger and pour. If using a jar, pour through a cheesecloth-lined fine-mesh strainer, then strain again through a paper filter for extra clarity.
5. Store the cold brew concentrate in the fridge for up to 2 weeks. To serve: dilute 1:1 with water or milk over ice.

Concentrate vs ready-to-drink

The recipe above makes a concentrate, strong enough that you'll want to dilute it. The advantage is compact storage and the ability to mix it to your taste each time.

For ready-to-drink cold brew, use a 1:15 ratio instead (for example, 50g coffee to 750g water). The result is closer to drip coffee strength and can be poured straight over ice.

Best beans for cold brew

Medium to medium-dark roasts work best. Darker roasts produce a chocolatey, smooth cup that's especially good with milk. Light roasts can work and produce a brighter, fruitier cold brew, but the smoother body of medium-dark is what most cold brew drinkers prefer.

Single-origin coffees with chocolate, nut, or caramel notes, such as Brazilian, Colombian, and Costa Rican, tend to shine. Very light African roasts work less well unless you specifically want a fruity cold brew.

Common mistakes

• Grind too fine. Slow filtration becomes painful and the cup gets murky.
• Not enough coffee. Cold brew uses more coffee per cup than hot methods. The slower extraction needs more material.
• Over-steeping. Past 24 hours, cold brew gets bitter and tannic. Set a timer.
• Steeping on the counter. Cold brew should steep in the fridge, not at room temperature.

Hot brew over ice (a faster alternative)

If you want iced coffee in 4 minutes instead of 18 hours, brew a regular V60 or AeroPress directly over ice. Use two-thirds the normal water; the melting ice makes up the rest. Different drink, much faster result.