Your Guide to Making Cold Brew Coffee

Quick answer

• Use coarse grounds and cold water. Steep for 12-24 hours.
• Strain thoroughly for a smooth cup.
• Dilute the concentrate to taste.
• Experiment with steep times and ratios.
• Cold brew is less acidic and smoother than hot coffee.
• Store concentrate in the fridge for up to two weeks.

Who this is for

• Anyone who likes a smooth, low-acid coffee.
• People who want to make coffee ahead of time.
• Those who find hot coffee too acidic or bitter.

What to check first

• Brewer type and filter type: Are you using a dedicated cold brew maker, a French press, or just a jar and a fine-mesh strainer? Each needs a slightly different approach. A finer filter means less sediment.
• Water quality and temperature: Use filtered water if your tap water has a strong taste. Cold brew uses cold water, so no need to worry about heating it up. That’s the beauty of it.
• Grind size and coffee freshness: Coarse grind is key. Think breadcrumbs, not powder. Freshly ground beans make a big difference. Old beans can taste flat.
• Coffee-to-water ratio: A good starting point is 1:4 for concentrate. This means 1 part coffee to 4 parts water. You’ll dilute this later.
• Cleanliness/descale status: Make sure your brewing equipment is clean. Old coffee oils can turn rancid and ruin your batch.

Step-by-step (brew workflow)

1. Measure your coffee. Use a coarse grind. For a 1:4 ratio concentrate, aim for about 1 cup of coffee grounds for every 4 cups of water. Good looks like: Evenly portioned grounds. Mistake to avoid: Not measuring, leading to inconsistent results. Use a scale for best accuracy.

2. Add coffee to your brewer. This could be a French press, a dedicated cold brew maker, or a large jar. Good looks like: All grounds are ready to be submerged. Mistake to avoid: Packing the grounds too tightly, which can hinder water saturation.

3. Pour in cold, filtered water. Start with about half the total water. Good looks like: All grounds are wet. Mistake to avoid: Using hot water. This is cold brew, remember? Stick to cold.

4. Stir gently. Make sure all the coffee grounds are saturated. Good looks like: No dry clumps of coffee. Mistake to avoid: Over-stirring, which can lead to over-extraction and bitterness.

5. Add remaining water. Pour in the rest of the water to reach your desired ratio. Good looks like: The water level is consistent. Mistake to avoid: Adding water too quickly, which can create uneven saturation.

6. Cover and steep. Place the lid on your brewer or cover your jar. Let it sit at room temperature or in the fridge. Good looks like: The brewer is sealed. Mistake to avoid: Leaving it uncovered, which can let in unwanted odors or contaminants.

7. Steep for 12-24 hours. Longer steeping generally means a stronger, more concentrated brew. Good looks like: Patience. Mistake to avoid: Under-steeping (weak coffee) or over-steeping (bitter coffee). 18 hours is a solid middle ground.

8. Strain the coffee. This is crucial. Use a fine-mesh sieve, cheesecloth, or a dedicated cold brew filter. Double-straining is often best. Good looks like: Clear liquid, minimal sediment. Mistake to avoid: Rushing the straining process, leaving gritty bits in your brew.

9. Dilute to taste. The strained liquid is concentrate. Mix it with water or milk. A common starting point is 1:1 ratio (equal parts concentrate and water/milk). Good looks like: A balanced, enjoyable flavor. Mistake to avoid: Drinking the concentrate straight. It’s potent!

10. Serve and enjoy. Pour over ice. Add your favorite milk or creamer. Good looks like: A refreshing beverage. Mistake to avoid: Not serving it cold. Cold brew is meant to be chilled.

Common mistakes (and what happens if you ignore them)

Mistake	What it causes	Fix
Using fine coffee grounds	Over-extraction, bitter and muddy coffee	Use a coarse grind (like coarse sea salt).
Not stirring enough	Uneven extraction, weak spots in the brew	Stir gently to ensure all grounds are wet.
Over-steeping (over 24 hours)	Bitter, astringent, and unpleasant flavor	Stick to the 12-24 hour window. Taste and adjust next time.
Under-steeping (less than 12 hours)	Weak, watery, and sour coffee	Increase steeping time.
Using tap water with strong flavors	Off-flavors in the final brew	Use filtered or bottled water.
Not straining thoroughly	Gritty, sediment-filled coffee	Double-strain with a fine-mesh sieve and/or cheesecloth.
Not diluting the concentrate	Overpowering, too intense flavor	Dilute with water or milk to your preferred strength.
Storing the concentrate improperly	Rancid flavors, spoilage	Store in an airtight container in the refrigerator.
Using old, stale coffee beans	Flat, dull, and lifeless flavor	Use freshly roasted, quality beans.
Packing coffee grounds too tightly	Poor water circulation, uneven extraction	Gently add grounds, don’t compress them.

Decision rules (simple if/then)

• If your cold brew tastes bitter, then try a shorter steep time or a coarser grind because over-extraction is likely the culprit.
• If your cold brew tastes weak, then try a longer steep time or a higher coffee-to-water ratio because you’re probably under-extracting.
• If you see a lot of sediment, then use a finer filter or strain twice because your filtering method isn’t catching all the fines.
• If your cold brew has an unpleasant, sour taste, then check your steep time and ensure you’re using cold water because sourness can indicate under-extraction or using water that isn’t truly cold.
• If you’re brewing in a French press and it’s muddy, then be extra careful when plunging and pouring to leave the fines behind because French presses don’t filter as finely as dedicated systems.
• If your cold brew concentrate tastes stale, then check the freshness of your beans and your storage method because old beans or improper storage will degrade flavor.
• If you want a smoother finish, then ensure your grind is consistently coarse and your straining is meticulous because fine particles contribute to a rough mouthfeel.
• If you’re short on time, then aim for the lower end of the steep time (12 hours) but accept it might be less concentrated, because speed often sacrifices depth.
• If you notice an off-flavor, then clean your equipment thoroughly because residual oils can go rancid.
• If you prefer a bolder flavor without extra bitterness, then increase the coffee-to-water ratio slightly rather than just steeping longer because this can boost strength more cleanly.

FAQ

How do you make a cold brew coffee concentrate?

Use a coarse coffee grind and cold water, typically at a 1:4 ratio of coffee to water. Steep for 12-24 hours, then strain thoroughly. This concentrate will be strong and needs dilution.

Can I use any coffee beans for cold brew?

Yes, but medium to dark roasts often yield a smoother, richer flavor profile that complements cold brew well. Lighter roasts can sometimes come across as too bright or acidic.

How long does cold brew last?

Stored in an airtight container in the refrigerator, cold brew concentrate can last up to two weeks. The flavor might degrade slightly over time, so fresh is always best.

What’s the difference between cold brew and iced coffee?

Cold brew is brewed with cold water over a long period, resulting in a less acidic, smoother concentrate. Iced coffee is typically hot-brewed coffee that has been cooled down and served over ice, often retaining more of its original acidity.

Why is cold brew less acidic?

The cold water extraction process pulls fewer acidic compounds from the coffee grounds compared to hot water brewing. This results in a naturally smoother and gentler cup.

How do I dilute cold brew?

Start with a 1:1 ratio of concentrate to water or milk. Adjust based on your preference. Some people like it stronger, some weaker. Taste is king here.

Can I use a regular coffee maker for cold brew?

Not really. Cold brew requires a long steeping time with cold water, which a standard drip machine isn’t designed for. You’d need to adapt the process significantly, likely using a jar or pitcher.

What kind of water should I use?

Filtered water is best, especially if your tap water has a strong chlorine taste or mineral content. Good water makes good coffee, simple as that.

What this page does NOT cover (and where to go next)

• Specific cold brew maker reviews and comparisons.
• Advanced flavor infusion techniques (e.g., adding spices during brewing).
• Detailed breakdown of different coffee roast profiles for cold brew.
• Troubleshooting for very specific equipment issues.