Easy Cold Brew Coffee Recipe Using A Mason Jar

Quick answer

• Use a coarse grind. Think sea salt.
• Aim for a 1:4 coffee-to-water ratio. That’s 4 oz coffee to 16 oz water for a pint jar.
• Steep for 12-24 hours. Longer means stronger.
• Filter it well. Cheesecloth or a fine-mesh sieve works.
• Dilute to taste. Cold brew concentrate is potent.
• Use good water. Filtered is best.

Who this is for

• Anyone who loves smooth, low-acid coffee.
• Campers and travelers who want great coffee on the go.
• Folks who want to ditch the bitter edge of hot brewed coffee.

What to check first

• Brewer type and filter type: You’re using a mason jar. That’s your brewer. For filtering, you’ll need something fine. Cheesecloth, a fine-mesh sieve, or even a clean coffee filter can work. A paper filter might clog, so be ready to rinse or double up.
• Water quality and temperature: Cold brew uses cold water, naturally. Filtered water is key here. Tap water can have off-flavors that really come through in a slow brew. Room temperature is fine for steeping.
• Grind size and coffee freshness: This is critical. You need a coarse grind. If it’s too fine, your cold brew will be muddy and over-extracted. Think coarse kosher salt or even peppercorns. Freshly ground beans are always better.
• Coffee-to-water ratio: For a mason jar, a good starting point is 1:4. For a 16 oz pint jar, that’s about 4 oz of coffee grounds to 16 oz of water. You can adjust this later.
• Cleanliness/descale status: Make sure your mason jar is spotless. Any residue can affect the taste. Since you’re not heating anything, descaling isn’t a big worry for the jar itself, but clean is clean.

Step-by-step (brew workflow)

1. Measure your coffee. For a 16 oz jar, start with about 4 oz of whole beans.

• What “good” looks like: You’ve got a solid amount of beans.
• Common mistake: Using pre-ground coffee that’s too fine. Avoid this by grinding your own beans right before you start.

2. Grind your coffee coarse. Aim for a consistency like coarse sea salt.

• What “good” looks like: Visible, chunky grounds.
• Common mistake: Grinding too fine. This leads to sediment and bitterness. If your grinder has settings, use the coarsest one.

3. Add grounds to the mason jar. Pour the coarsely ground coffee into your clean jar.

• What “good” looks like: The jar is filled to the appropriate level for your ratio.
• Common mistake: Overfilling the jar with grounds. You need space for the water to circulate.

4. Add filtered water. Pour in about 16 oz of cold or room-temperature filtered water.

• What “good” looks like: All the grounds are saturated. You can give it a gentle stir.
• Common mistake: Using hot water. This defeats the purpose of cold brew and can lead to bitterness. Stick to cold or room temp.

5. Stir gently. Make sure all the coffee grounds are wet.

• What “good” looks like: A muddy slurry where all grounds have met water.
• Common mistake: Vigorous stirring. You don’t want to agitate it too much. Just ensure saturation.

6. Seal the jar. Screw on the lid tightly.

• What “good” looks like: A secure seal. No leaks.
• Common mistake: Not sealing it properly. This can lead to evaporation or spills.

7. Let it steep. Place the jar in the fridge or on your counter. Steep for 12 to 24 hours.

• What “good” looks like: Time is passing, and the magic is happening. Longer steeping means stronger coffee.
• Common mistake: Not steeping long enough. You won’t get that rich, concentrated flavor. Give it at least 12 hours.

8. Prepare your filtering setup. Line a clean bowl or another jar with cheesecloth, a fine-mesh sieve, or a coffee filter.

• What “good” looks like: Your filtering station is ready to catch the grounds.
• Common mistake: Using a filter that’s too fine for a large batch. It will clog. Start with a sieve or cheesecloth.

9. Strain the coffee. Slowly pour the steeped coffee through your filter setup. You might need to do this in batches.

• What “good” looks like: Clear, dark liquid dripping into the clean container.
• Common mistake: Pouring too fast. This can overwhelm your filter and let grounds through. Patience is key.

10. Filter again if needed. If you see sediment, strain it a second time.

• What “good” looks like: Your cold brew is smooth and free of grit.
• Common mistake: Settling for gritty coffee. A quick second strain makes a big difference.

11. Dilute to taste. Your cold brew concentrate is strong. Mix it with water or milk, hot or cold, to your liking.

• What “good” looks like: A perfectly balanced cup of coffee.
• Common mistake: Drinking the concentrate straight. It’s potent stuff! Always dilute.

Common mistakes (and what happens if you ignore them)

Mistake	What it causes	Fix
Using pre-ground coffee (too fine)	Muddy, bitter, over-extracted coffee	Grind your own beans coarsely.
Not using filtered water	Off-flavors, less clean taste	Use filtered or bottled water.
Not steeping long enough (under 12 hrs)	Weak, watery coffee, lacking flavor	Steep for at least 12 hours, up to 24.
Steeping too long (over 24 hrs)	Can become bitter or overly acidic	Stick to the 12-24 hour window. Taste as you go.
Using a too-fine filter	Clogged filter, messy straining, sediment	Use a coarse grind and filter with a sieve or cheesecloth first.
Not stirring to saturate grounds	Uneven extraction, weak spots in the brew	Gently stir to ensure all grounds are wet.
Drinking the concentrate straight	Overly intense flavor, can upset your stomach	Dilute with water, milk, or ice to taste.
Not cleaning the jar thoroughly	Stale flavors, off-notes in your cold brew	Wash the jar well before and after use.
Using hot water for steeping	Defeats the purpose of cold brew, potential bitterness	Always use cold or room-temperature water.

Decision rules (simple if/then)

• If your cold brew tastes weak, then steep it longer next time because you didn’t extract enough flavor.
• If your cold brew is bitter, then try a coarser grind or a shorter steep time because over-extraction causes bitterness.
• If you have sediment in your final cup, then filter it again through a finer mesh or paper filter because your initial filtering wasn’t sufficient.
• If you’re short on time, then steep for 12 hours because that’s the minimum for decent flavor.
• If you prefer a stronger, more concentrated coffee, then use a higher coffee-to-water ratio (e.g., 1:3) because more coffee means more flavor.
• If your tap water tastes funky, then use filtered water because it will improve the final taste.
• If you’re making a big batch, then use a large mason jar (like a half-gallon) because it’s more efficient.
• If you want to avoid a muddy brew, then ensure your grind is coarse enough because fine grounds are the main culprit.
• If you find cold brew too acidic, then try a longer steep time (up to 24 hours) because longer extraction can mellow out acidity.
• If you’re storing your cold brew, then keep it in a sealed container in the fridge because it stays fresh for about a week.

FAQ

What kind of coffee beans should I use for cold brew?

Any medium to dark roast beans work well. Avoid very light roasts as they might not extract as smoothly. Freshness is more important than the specific origin.

How long can I store cold brew concentrate?

It’s best to use it within a week when stored in an airtight container in the refrigerator. After that, the flavor can start to degrade.

Can I use a paper coffee filter for straining?

Yes, but it might clog quickly if your grind is even slightly too fine. You might need to rinse it or use a sieve first.

Why is my cold brew cloudy?

This usually means your grind was too fine, or your filtering wasn’t thorough enough. Coarse grounds and a good straining process are key.

Does the type of water really matter?

Absolutely. If your tap water has chlorine or other mineral tastes, they will be amplified in cold brew. Filtered water yields a cleaner, more pure coffee flavor.

How do I make it less bitter?

Try a coarser grind, a shorter steep time, or ensure you’re not over-extracting. Sometimes, a slightly higher coffee-to-water ratio can also help balance bitterness.

What’s the best coffee-to-water ratio for mason jar cold brew?

A good starting point is 1:4 (e.g., 4 oz coffee to 16 oz water). You can adjust this based on how strong you like your coffee.

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

• Specific coffee bean origins and their flavor profiles.
• Advanced cold brew techniques like nitrogen infusion.
• Detailed comparisons of different cold brew maker systems.
• Espresso-based drinks made from cold brew concentrate.