A tall, frosty glass of cold brew coffee is perfect for when you’re craving something cool — but what’s the correct way to prepare cold brew? In this handy guide, we’ll show you how to make the perfect cold brew at home.
Cold brew coffee is said to have been first popularised in 17th century Japan. The Japanese people were among the first to cold brew tea, and soon set their sights on coffee, after witnessing Dutch traders enjoying pre-prepared coffee on their ships that didn’t need heating up.
Nowadays, ‘Kyoto-style’ coffee is made by letting water slowly drip over coffee grounds in suspended glass columns, while various other iterations of cold brew have spread around the world. In the 1960s, American inventor Todd Simpson created the ‘Toddy’ system to batch-prepare cold brew — and this smooth, ‘true’ chilled coffee has since become a staple among aficionados.
Cold brew is a strong, highly concentrated coffee drink made by steeping coffee grounds in cold water for up to 24 hours. This produces a smooth, flavoursome brew with a trademark sweetness, as the cold water that the grounds are steeped in extracts fewer of the compounds that can make hot coffee bitter.
You’d be forgiven for mixing up these two cooling coffee drinks, but cold brew and iced coffee are quite different. To make iced coffee, coffee is typically brewed hot and made cold afterwards. This heat releases acids into the coffee which become a little bitter when cooled. Cold brew escapes this fate, because cold water doesn’t have the same effect — and the drink tends to taste both stronger and sweeter than iced coffee.
Thanks to its longer extraction time, cold brew is usually higher in caffeine than other coffee drinks. The average cold brew contains 150-200mg of caffeine, though the exact amount depends on the coffee bean used and the time it’s left to steep.
If you’re adding milk to your cold brew, we recommend using fresh, whole dairy milk. This helps to create a creamy mouthfeel while softening the bold flavour of the coffee, which some may find overpowering. If you’re using a dairy-free substitute, options like almond, soy or oat work nicely. Alternatively, some cold brew lovers even add a little coconut milk to act as a sweet creamer.
Because cold brew coffee has a longer shelf life than other brewing techniques, many choose to prepare a batch in advance and then refrigerate it for later use. And while it’s usually served cool, you can heat cold brew back up again in the microwave or on the stove when you’re in the mood for hot coffee. Fortunately, heated cold brew maintains its smoothness and sumptuously sweet flavour.