Cold brew: brewed cold, gentle and strong

Cold brew is not cooled down coffee, it is a different drink. Over many hours, cold water dissolves sugars, oils and bitter compounds differently from hot water: it pulls fewer acids and fewer volatile floral notes, and plenty of chocolate, nut and body instead. That is why cold brew tastes round, sweet and gentle, even from beans that would be sharp brewed hot.

The recipe for concentrate

1. Grind 100 grams of coffee very coarse, coarser than for a french press.
2. Put it in a french press, a large jar or a carafe and pour on 800 grams of cold filtered water. Stir until everything is wet.
3. Cover and leave in the fridge for 12 to 16 hours. At room temperature eight to ten hours is enough; the result is a little stronger and less clean.
4. Strain through a paper filter or a fine cloth. Do not squeeze it, that brings bitterness.
5. Pour the concentrate into a bottle and keep it cold.

Serving

Dilute the concentrate 1:1 with cold water and serve over ice. With milk or oat milk 1:1 it becomes a cold brew latte. A splash of tonic water and a strip of orange zest turn it into a bitter summer drink. If you prefer it hot, top the concentrate up with hot water; it tastes milder than freshly brewed coffee.

Cold brew, iced coffee, Japanese iced coffee

• Cold brew: extracted cold over hours, soft and sweet, little acidity.
• Iced coffee: hot brewed coffee, cooled down. It loses aromas while cooling and often turns musty.
• Japanese iced coffee: brewed hot, but filtered straight onto ice. Brew with half of the water as ice in the carafe. Clean, fruity, bright. The opposite of cold brew.

Caffeine

Concentrate holds more caffeine per millilitre than filter coffee; diluted, the two are roughly level. Because cold brew tastes so mild, it is easy to drink more of it. The caffeine calculator helps you estimate.

Shelf life

In a closed container the concentrate keeps for about a week in the fridge. After that it turns increasingly sour, because micro organisms and oxidation are at work. Diluted cold brew keeps for less, around three days.