How to Make Cold Brew Coffee: Ratio, Grind Size, and Steep Time
Cold brew extracts coffee with cool water over many hours. The method produces a concentrated, smooth beverage, but it can still taste bitter, muddy, sour, or weak when grind size, ratio, filtration, and time are poorly matched.
Choose ready-to-drink or concentrate
A ready-to-drink recipe uses more water and can be served after filtration. A concentrate uses more coffee and is diluted with water or milk. Measuring by weight creates more repeatable results.
- Ready to drink: begin near 1 part coffee to 12–16 parts water.
- Concentrate: begin near 1 part coffee to 5–8 parts water, then dilute to taste.
These are starting ranges. Roast level and desired strength may require adjustment.
Grind size
Use a coarse grind, but do not assume the coarsest possible setting is correct. Coffee that is extremely coarse may under-extract and taste hollow. Excessive fines can make filtration slow and the beverage muddy.
Steep time
Many room-temperature or refrigerated recipes fall within roughly 12–24 hours. Cooler extraction generally progresses more slowly. Begin with one time and change it only after tasting the filtered brew.
Basic method
- Weigh coffee and water.
- Combine them in a clean food-safe container.
- Stir gently until all grounds are wet.
- Cover and steep at a controlled temperature.
- Filter through a coarse screen, then paper if greater clarity is desired.
- Dilute concentrate and serve over ice.
Troubleshooting
- Sour and weak: grind slightly finer, steep longer, or use more coffee.
- Bitter and woody: grind coarser, shorten the steep, or dilute further.
- Muddy: reduce fines and improve filtration.
- Flat aroma: use fresher coffee and protect the brew from oxygen and odors.
Roast and origin
Medium and darker roasts often produce chocolate-forward cold brew. Light roasts can create fruit and floral notes but may need finer grinding or a longer extraction. Natural-process coffees can add strong berry character.
Storage and cleanliness
Refrigerate filtered cold brew in a clean sealed container and use conservative food-handling practices. Discard it if aroma, flavor, or appearance becomes questionable. Clean brewing and filtering equipment thoroughly after every batch.
A grinder with broad adjustment range, including the Turin DF64 Gen 2.7, makes it easier to test cold-brew grind sizes while maintaining measured doses.
