How to make better cold brew at home

Our simple cold brew concentrate recipe — and why the coffee you choose makes more difference than you might think.

Summer in the Algarve means a few things.

Tourists. Beaches. Trying to find somewhere to park.

And cold brew.

We make a lot of cold coffee at Al-Gharb Coffee Roasters all year around, but the good news is that cold brew is probably one of the easiest coffee drinks to make properly at home.

You don't need an expensive machine.

You don't need any particularly impressive barista skills.

You mostly need coffee, water, a French Press...

...and patience.

Unfortunately, that last ingredient takes about 12 hours.

☕ My cold brew recipe

If you just want the recipe, here it is:

Coffee: 100g

Water: 800ml

Grind: Very coarse

Water temperature: Cold

Brew time: Around 12 hours

Where: In the fridge

This makes a cold brew concentrate, rather than something I'd recommend drinking straight.

Once it's ready, I normally start with:

150ml cold brew concentrate

100ml water, milk or tonic

Plenty of ice

Adjust it from there depending on how strong you like it.

Simple.

Now let's talk about why.

What coffee should you use for cold brew?

You can make cold brew with almost any coffee.

But that doesn't mean every coffee will give you the same result.

Personally, I really like coffees with plenty of chocolate, caramel and nutty flavours for cold brew.

A Brazilian coffee works particularly well.

The long, cold extraction tends to produce a very smooth drink with low perceived bitterness, and those chocolatey flavours work beautifully over ice or with milk.

At Al-Gharb we've often used our Brazil Cerrado for exactly this reason.

But you can absolutely experiment.

A fruitier coffee can produce a completely different cold brew.

And that's where things get interesting.

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Grind much coarser than you think

Cold brew needs a coarse grind.

Actually, I'd grind even coarser than I normally would for French Press.

We're going to leave this coffee sitting in water for hours, not minutes.

If you grind too finely, extraction happens much faster and you can end up with something muddy, harsh and difficult to filter.

So:

Espresso: fine.

V60: medium-ish.

French Press: coarse.

Cold brew: we're heading towards small gravel.

Not literally.

Please don't put gravel in your grinder.

Step 1: Coffee meets water

Put 100g of coarsely ground coffee into your French Press.

Add 800ml of cold water.

Give everything a good stir.

You want to make sure all the coffee is completely wet rather than having dry islands floating around on top.

Put the lid loosely on the French Press.

Don't plunge it yet.

Now put the whole thing in the fridge.

And wait.

Step 2: The difficult part

We normally leave ours for around 12 hours.

Overnight is perfect.

Make it after dinner and deal with it in the morning.

There is no need to stand in front of the fridge watching it.

It doesn't help.

But 12 hours isn't a law

This is important.

Different coffees behave differently.

A chocolatey Brazilian coffee might work beautifully after 12 hours.

A brighter, fruitier coffee might taste better with a shorter extraction.

So if you're experimenting with a very fruity coffee, start tasting it earlier.

Maybe 8 hours.

Maybe even less.

Coffee recipes should always be treated as starting points, not commandments.

Your get the final vote.

Step 3: Plunge slowly

Once the gruelling wait is finally over, slowly press down the French Press plunger.

You'll probably notice that the coffee isn't perfectly clean.

There may be small particles floating around.

Technically, you could stop here.

But I don't.

The extra step that makes a much better cold brew

I like to filter the concentrate again through a paper coffee filter.

A V60 works perfectly.

Pour the cold brew through the paper filter and you'll see exactly what it removes.

Fine coffee particles and sediment that would otherwise end up in your glass are caught by the paper.

The result is a noticeably cleaner and smoother cold brew.

It takes another couple of minutes.

It's worth it.

How to drink it

Remember: we've made a concentrate.

My starting point is:

150ml cold brew concentrate

plus approximately:

100ml water

or

100ml milk

or, one of my favourites:

100ml tonic water

Then add plenty of ice.

Don't be afraid to adjust the ratio.

Want it stronger? Add less water.

Too strong? Add more.

Again, nobody from the Specialty Coffee Police is coming to check your glass.

🧊 Cold brew + tonic

If you've never tried cold brew with tonic water, do.

Ice into the glass.

Cold brew concentrate.

Tonic.

A slice of orange works very well too.

It's slightly bitter, slightly sweet, refreshing and dangerously easy to drink when it's 35°C outside.

Which, in the Algarve, happens occasionally.

How long does cold brew last?

Keep your concentrate covered and refrigerated.

Personally, I think cold brew is best when it's relatively fresh. Over time the flavour will start changing and losing some of its brightness.

So rather than making enough to survive until Christmas, make a batch you'll actually drink.

That's also a good excuse to make another one.

Can I use old coffee for cold brew?

Yes.

Cold brew can actually be quite forgiving.

If you have coffee that's slightly past its best for espresso or V60, experimenting with cold brew is much better than throwing it away.

But there's a limit.

Cold brew isn't magic.

If your beans have been sitting open in a cupboard since 2019, making them cold isn't going to bring them back to life.

Good coffee still makes better cold brew.

My cold brew rule

If there's one thing I'd take from this recipe, it's this:

Don't obsess over the 12 hours.

Coffee, grind size, temperature and personal taste all change the result.

Use:

100g coffee + 800ml water + 12 hours

as your starting point.

Then experiment.

Try 10 hours.

Try a different coffee.

Try a fruitier natural coffee.

Try it with tonic.

Change one thing at a time and see what you prefer.

That's half the fun.

And now the final step...

Pour your cold brew over plenty of ice.

Add water, milk or tonic.

Taste it.

Adjust it.

And then...

Go find your closest beach.

You've done enough work for today.

— Henning Al-Gharb Coffee Roasters, Algarve

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