Cold Brew Coffee: What It Is and How to Make It at Home

Cold brew has gone from a niche café trend to a supermarket shelf staple in the space of a decade, and it's easy to make well at home with almost no equipment. Here's what makes it different from other coffee, and how to make a genuinely good batch yourself.

The quick answer

Cold brew is coffee steeped in cold or room-temperature water for an extended period — typically 12-24 hours — rather than brewed quickly with hot water. This slow, cold extraction produces a smooth, naturally sweet, low-acidity concentrate that's usually diluted with water, milk or ice before drinking. It's a method, not a bean or roast level, and it can be made at home with nothing more than a jar, a filter and time.

Why Cold Water Changes Everything

Hot water extracts flavour compounds from coffee quickly, including some of the more acidic and bitter ones. Cold water extracts much more slowly and selectively, pulling out sweetness and body while leaving more of the sharper acids and bitter compounds behind. That's the entire secret behind cold brew's famously smooth, mellow character — it's a function of temperature and time, not a special bean or roast.

Cold Brew vs Iced Coffee: Not the Same Thing

These two are often confused, but they're genuinely different: cold brew is brewed cold from the start, while iced coffee is regular hot-brewed coffee cooled down and served over ice. This matters for flavour — cold brew is smoother and less acidic, while iced coffee retains more of hot brewing's brightness and acidity. Our iced coffee guide covers this distinction in more depth.

How to Make Cold Brew at Home

Combine coarsely ground coffee with cold or room-temperature water at a ratio of roughly 1:8 (for a concentrate you'll dilute later) — for example, 100g of coffee to 800ml of water. Stir to make sure all the grounds are saturated, then leave to steep in the fridge or at room temperature for 12-24 hours. Strain through a fine mesh sieve followed by a paper filter (or a dedicated cold brew maker) to remove all sediment, then dilute the resulting concentrate with water, milk or ice to taste.

Choosing the Right Coffee for Cold Brew

A coarse, even grind is essential — too fine, and you'll get excessive sediment and over-extraction; too coarse, and the cup can taste weak or flat. Medium to dark roasts tend to work particularly well for cold brew, since they naturally lean toward chocolate and nutty notes that suit cold brew's smooth character, though lighter roasts can produce interesting fruit-forward cold brews too.

Storing Cold Brew Concentrate

Because it's low in acidity (which normally helps preserve brewed coffee) but has no preservatives, cold brew concentrate should be kept refrigerated and used within about 1-2 weeks for the best flavour. Always store it in a sealed container to prevent it from picking up fridge odours.

Common Misunderstandings About Cold Brew

A common myth is that cold brew has less caffeine than hot-brewed coffee — because it's typically made with a much higher coffee-to-water ratio, cold brew concentrate is often actually more caffeinated per millilitre before dilution. Another myth is that cold brew requires special equipment — while dedicated cold brew makers exist, a jar and a fine mesh strainer work perfectly well.

Why Choose Amici Coffee?

Amici Coffee is an independent UK coffee business with six carefully selected coffees, each with clear origin and tasting information rather than vague blend descriptions. Beans are roasted in partnership with a certified B Corp speciality coffee roasting partner that holds the highest B Corp score of any coffee roaster we work with — a genuinely world-leading, global leader in ethical coffee roasting. You can order online for delivery, visit our café in person, or set up a subscription so your coffee never runs out.

Frequently Asked Questions

Is cold brew the same as iced coffee?
No — cold brew is brewed cold from the start over many hours, while iced coffee is hot-brewed coffee cooled and served over ice.

How long should cold brew steep?
Typically 12-24 hours, depending on your grind size and desired strength.

Does cold brew have more caffeine than hot coffee?
Cold brew concentrate is often more caffeinated per millilitre due to its higher coffee-to-water ratio, though it's usually diluted before drinking.

What grind size is best for cold brew?
A coarse, even grind, similar to what you'd use for a French press.

How long does cold brew concentrate last?
About 1-2 weeks when refrigerated in a sealed container.

The Bottom Line

Cold brew's smooth, low-acidity character comes down to one simple factor — time and cold water instead of heat — and it's genuinely easy to make well at home with basic equipment.

Explore Amici's speciality coffees and find a cup that suits your taste, or set up a regular delivery so fresh coffee keeps arriving.