Cold Brew for Cafés: Coffee and Tea Ratios, Batch Method and Kit

For cold brew coffee, steep coarsely ground coffee in cold water at 1:10 — 60 g to 600 ml — in the fridge for 8–12 hours. For cold brew tea, use about 10 g of loose leaf per litre and steep for 2–8 hours, depending on the tea. Make both the night before and serve from the fridge.

Cold brew is the easiest summer serve a café can add. It’s made in batches when the bar is quiet, it needs no special machine, and it’s ready to pour the moment a customer asks. This guide takes Hario UK’s cold brew and cold brew tea guides and turns them into a method for a busy bar.

Why add cold brew to your menu?

1. It’s batch work, not service work. Make it at close; pour it the next day.
2. It’s smooth and low in acidity. Hario notes that the low acidity means cold brew doesn’t curdle milk, so it works black, with water or with milk.
3. It covers tea drinkers too. The same fridge space makes cold brew tea, a simple non-coffee option.
4. It sells the kit. Customers who like your cold brew want to make it at home, and the bottle you brew in sits on your retail shelf.

How do you make cold brew coffee?

1. Grind coarse — Hario describes it as about the texture of sea salt. Fine grounds over-extract and clog the filter.
2. Weigh the coffee and cold water at 1:10 — 60 g to 600 ml, or 100 g to 1 litre.
3. Combine, stir so all the coffee is wet, seal and put it in the fridge.
4. Steep for 8–12 hours. Twelve hours is Hario’s sweet spot for most coffees.
5. Remove the grounds, label the container with the date and keep it sealed in the fridge.

Steep in the fridge rather than at room temperature: Hario says it gives a cleaner result and is the safer option. Hario UK’s complete cold brew guide has the full method for customers.

How much coffee do you need for a batch?

Brew ready-to-drink cold brew at 1:10. If fridge space is tight, brew a 1:5 concentrate and dilute it to serve.

How long does cold brew keep?

Hario UK says cold brew coffee keeps for about a week in a sealed container in the fridge once the grounds are removed. Cold brew tea keeps for about three days, and green tea starts to lose its brightness after a day. Date every batch and work within your own food-safety procedures.

What can you serve with it?

1. Neat over ice — the simplest serve and the best test of the coffee.
2. Long with water or milk — the low acidity means milk won’t curdle.
3. Citrus cold brew — Hario UK’s two citrus cold brews mix cold brew and fresh juice at about 2:1. A bright, seasonal special that’s quick to build.

How do you make cold brew tea?

Use roughly 10 g of loose leaf tea per litre of cold water — about two heaped teaspoons — and steep it in the fridge. Steep time depends on the tea.

Rinse the bottle’s silicone seal regularly, especially after blends containing hibiscus. Hario UK’s cold brew tea guide covers the whole Filter-in range.

What kit do you need?

See the full cold brew range.

How do you sell cold brew kit at retail?

1. Brew in the same bottles you sell, and keep one on the counter.
2. Offer a bag of your coffee ground coarse and labelled “for cold brew”.
3. Put a recipe card with the ratio and steep time next to the bottles.
4. Stock up in spring: demand follows the first warm weekend.

For more summer menu ideas, see our guide to matcha for cafés.

Frequently asked questions

What is the ratio for cold brew coffee?
A standard ready-to-drink cold brew uses 1:10 — 60 g of coarsely ground coffee to 600 ml of cold water, or 100 g to a litre. For a concentrate to dilute later, use 1:5.

How long should cold brew steep?
Steep cold brew in the fridge for 8–12 hours. Hario UK calls 12 hours the sweet spot for most coffees; beyond 16 hours it gets heavier and woody and rarely improves.

How long does cold brew coffee last in the fridge?
Once the grounds are removed, Hario UK says cold brew coffee keeps for about a week in a sealed container in the fridge. Label each batch with the date it was made.

How much tea do you use for cold brew tea?
Use about 10 g of loose leaf tea per litre of cold water. Steep green and white teas for 2–3 hours, oolong and black for 4–6 hours, and herbal blends for 6–8 hours in the fridge.

Can you add milk to cold brew?
Yes. Cold brew is low in acidity, so it doesn’t curdle milk. Serve it over ice, lengthened with water or milk, or mixed with fresh citrus juice for a seasonal special.