Cold Brew Recipes, Straight From Our Roastery

At our Long Beach roastery, we brew cold brew for wholesale clients daily. After more than 500 batches, here's what actually works, and what absolutely doesn't.

Cold brew isn't a side project for us. It's something we produce at scale for kegs, bottles, and by-the-glass service. That means every variable, including ratio, grind size, steep time, and bean selection, has been tested repeatedly in real production conditions, not just once on a quiet Sunday afternoon.

Our roots trace back to Melbourne, Australia, a city known worldwide for its specialty coffee culture. Melbourne cafes were refining cold extraction techniques well before cold brew hit mainstream menus across the U.S., and that heritage shapes how we approach coffee at Common Room Roasters today, through thoughtful sourcing, careful roasting, and obsessive brewing standards.

Here, we're sharing what we've learned from hundreds of batches, including the exact ratios we use, how long we steep (and why), which coffee beans perform best, and the mistakes we see customers make over and over. If you want the real roastery process and not just a one-off food blog recipe, you're in the right place.

What Makes Cold Brew Worth the Effort

We brew cold brew daily for wholesale clients. Consistency isn't optional — if a batch runs thin, bitter, or flat, dozens of customers notice. Every variable gets evaluated. When you're brewing for wholesale accounts, consistency matters. If a batch runs thin, bitter, or flat, dozens of customers will notice, so we test continuously. We make small adjustments, choose new origins, experiment with different roast curves, and try out seasonal shifts.

Every change gets evaluated, and that production repetition is where the real learning happens. Melbourne's cafe culture shaped this mindset for us. In cities like Melbourne, coffee isn't an afterthought. Instead, it's a craft. Cold brew evolved there as a refined alternative to iced coffee, not just drip coffee poured over ice, with extraction clarity, mouthfeel, and sweetness all dialed in intentionally.

Steeping beyond 20 hours doesn't deepen flavor — it degrades it. Instead of richer chocolate notes, you'll start picking up papery, cardboard-like dryness. Instead of richer chocolate notes, we started picking up papery, cardboard-like dryness. That was a turning point in how we standardized our process.

This information isn't "here's a recipe I like." It's our actual roastery workflow, scaled down for you.

Our Favorite Beans for Cold Brew

Cold brew changes how coffee expresses itself. Acidity softens, and bright citrus notes fade, while chocolate, nut, and fruit undertones become more prominent or disappear entirely, depending on roast profile.

Roast Profile Matters

The roast profile is extremely important. Medium to medium-dark roasts tend to perform best for milk-based cold brew because they bring forward chocolate, caramel, and nutty depth. In contrast, very light roasts can lose their high-toned brightness during cold extraction, which leaves the cup muted or flat.

For cold brew with milk, we recommend Zaferia Blend. Its chocolate and toasted nut profile holds up beautifully when diluted and poured over ice. If you're a black cold brew drinker, we've had exceptional results with Ethiopia Ardi Sidama. The strawberry and cocoa notes survive extraction better than most light roasts, so instead of washing out, they round into something juicy and layered.

Other blends we've tested successfully include City Block Blend and Brunswick Blend, but the overlooked truth is that freshness matters just as much as origin. Cold brew relies heavily on aromatics for complexity, and whole coffee beans older than 3 to 4 weeks from roast date have already lost a significant portion of those volatile compounds. If your cold brew tastes dull, check the roast date before blaming the ratio.

Cold Brew Ratio: What We Use for Wholesale vs. Home

After hundreds of production batches, we've standardized on a 1:4 coffee-to-water ratio for wholesale concentrate, because cold brew concentrate gives us flexibility. It allows for important benefits, including:

• Consistent dilution control

• Better shelf stability

• Easier kegging and bottling

• Portion flexibility for cafes

A strong concentrate diluted 1:1 with water or milk creates balance without sacrificing body, and for home brewers who plan to drink it within a week, a 1:8 ratio works beautifully as a ready-to-drink cold brew.

Comparison Table: Cold Brew Ratios

For café-style versatility, go 1:4. For simplicity at home, 1:8 is the best choice..

Getting Cold Brew Right

Here's our step-by-step scaled-down production method for home brewing.

1. Measure Your Coffee: Choose either a 1:4 or a 1:8 ratio.

2. Grind Coarse: Grind size should be coarse, like sea salt. On a Baratza Encore coffee grinder, for example, on a French press setting. Too fine coffee grounds will give you over-extraction and sludge, while too coarsely ground coffee will be weak and underdeveloped.

3. Add Water and Stir Thoroughly: Combine coffee and filtered water. Then, stir intentionally. Dry pockets under-extract and throw off the whole batch. We agitate every batch during production to ensure full saturation.

4. Steep 16 to 18 Hours: Room temperature is preferred, but refrigeration is acceptable if necessary. Just add 2-4 extra hours to your steep time.

5. Filter: Your main options for a coffee filter are a French press (press gently), cheesecloth over a sieve, or a nut milk bag. You can check out options in our French press category and brew gear collection to dial in your setup.

6. Store Airtight: Transfer to a sealed container and refrigerate immediately.

Common Cold Brew Mistakes (And How to Fix Them)

These are the most common mistakes we see — and how to fix them. The first is a weak or watery cold brew, and the problem is usually the grind size. Pre-ground coffee is almost always too fine and actually under-extracts in immersion brewing. It could also be that you're simply not using enough coffee. Try a fresh grind and increase the amount.

Bitter cold brew is another problem, with three main causes: over-steeping past 24 hours, using too fine a grind, and brewing in a very warm kitchen. To fix this issue, you'll want to dial back your steep time and coarsen the grind.

Another common complaint when making cold brew at home is that it doesn't taste like a coffee shop. That's often because most shops use fresh-roasted specialty coffee. Check your roast date, because anything older than 3 to 4 weeks has lost significant aromatics.

How We Store Cold Brew (Production vs. Home)

For wholesale, we use kegs, nitro, and bottles because oxygen control is critical at scale. At home, you can keep it simple. Choose an airtight container, refrigerate immediately, and store away from strong odors.

Timeframes matter, as well. For concentrated cold brew, you can store it for 10 to 14 days refrigerated, while diluted cold brew can only be stored for five to seven days refrigerated. After that, the flavor drops noticeably.

FAQ: Cold Brew Coffee Questions

What is the best ratio for cold brew coffee?

For concentrate, 1:4, and for ready-to-drink at home, 1:8.

How long should cold brew steep?

Sixteen to 18 hours at room temperature, but be sure to add 2 to 4 hours if you're brewing in the fridge.

Can I use pre-ground coffee for cold brew?

You can, but the results are inconsistent. Fresh, coarse grinding makes a major difference.

Why is my cold brew bitter?

Likely over-steeping, too-fine a grind, or warm brewing conditions.

What beans are best for cold brew?

Medium to medium-dark for milk drinks (like Degraves Lane Blend), and fruit-forward single origins like Ethiopia Ardi Sidama for black cold brew.

Can you heat up cold brew coffee?

Yes. Dilute the concentrate first, then gently warm, but don't boil it — high heat strips everything that makes cold brew smooth.

How long does cold brew last in the fridge?

Ten to 14 days for concentrate and 5 to 7 days for ready-to-drink.

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

Cold brew is extracted cold over many hours, while iced coffee is hot brewed coffee and then chilled. Cold brew is typically smoother and less acidic.

Start Brewing With Common Room Roasters

If you're serious about your cold brew, it starts with the right beans. We've curated a full range of coffees specifically selected for cold extraction — from chocolate-forward blends to fruit-driven single origins — each one roasted to perform at its best when brewed cold. Cold brew doesn't have to be complicated, but it does reward precision. Shop our favorite beans for cold brew here.