Cold brew coffee is made by steeping coarsely ground coffee in cold (or room temperature) water for an extended period — usually 12 to 24 hours. No heat is involved, which means extraction is slow and gentle, producing a concentrate that's smooth, low-acid, and remarkably sweet-tasting.
The problem with most cold brew is the ratio. Standard brewing ratios for hot coffee (1:15 or 1:16) make cold brew that tastes thin and flavourless. Cold brew needs a stronger starting ratio because it's typically diluted with water or milk before drinking.
☕ The Recipe
Method
- Grind your coffee coarsely — the consistency of raw sugar or coarse sea salt. A coarser grind reduces bitterness during the long steep and makes filtering easier.
- Combine coffee and cold water in a large jar or container. Stir briefly to ensure all the grounds are wet.
- Cover and refrigerate for 12–18 hours. Don't exceed 24 hours, or it starts to taste flat and papery.
- Filter the concentrate through a fine mesh strainer lined with a paper filter or cheesecloth. Don't press or squeeze the grounds — this adds bitterness.
- Store in a sealed bottle in the fridge for up to 2 weeks.
How to Serve It
This recipe produces a concentrate. To drink it, dilute with cold water or milk at roughly a 1:1 ratio. You can adjust to taste — more water for lighter, less for stronger. Over ice, it's particularly good.
Why This Ratio Works
A 1:6 ratio (100g coffee to 600ml water) sounds strong — and it is. But cold brew is meant to be a concentrate. At this ratio, diluted 1:1 with water before serving, you end up at the equivalent of a roughly 1:12 brew — similar strength to a strong drip coffee, but without any of the bitterness or acidity that heat creates.
Common Cold Brew Mistakes
- Grind too fine: Fine grinds over-extract and make filtering a nightmare
- Too weak a ratio: 1:10 or weaker produces watery concentrate that doesn't improve when diluted
- Steeping too long: Past 24 hours, cold brew tastes flat and woody
- Squeezing the filter: Forces bitter compounds into your concentrate
- Using hot water: That's just regular coffee. Cold brew needs cold water.