Ozone Brew Guide | Cold Brewed Coffee


How to Make Cold Brew Coffee at Home

Cold brewed coffee being poured into a glass over ice

Easy Recipe, Brewing Tips & Serving Ideas

Cold brew coffee has transformed how we enjoy coffee—especially during warmer months. Unlike iced coffee, which is brewed hot and then chilled, cold brew is made using cold water from start to finish. The result? A naturally sweet, smooth, and low-acidity coffee concentrate that’s perfect over ice, with milk, or even in cocktails.

Whether you're new to cold brew or looking to perfect your method, this guide will walk you through everything you need to know to brew a delicious cold specialty coffee.

What is Cold Brew Coffee?

Cold brew is a method of brewing coffee slowly using cold or room-temperature water. The extended brew time—typically 12 to 18 hours—extracts deep flavours while reducing bitterness and acidity. The result is a rich, concentrated coffee that can be diluted to taste. Don't have 12-18 hours and just want a cold coffee right now? Make sure to check out our brew guide for Japanese-style flash brew!

Best Coffee for Cold Brew

For the best results, choose coffees with natural sweetness and low acidity. We recommend using a medium to coarse grind—similar to French press grind. Our Hodson espresso blend works beautifully for cold brew, offering chocolatey depth and a smooth finish.

Cold Brew Coffee Recipe

For 6 Cups of Diluted Cold Brew:

  • 100g coarsely ground coffee (French Press grind)
  • 400ml cold, filtered water
  • Yields: ~200ml cold brew concentrate

For 16 Cups of Diluted Cold Brew:

  • 250g coarsely ground coffee (French Press grind)
  • 1 litre cold, filtered water
  • Yields: ~500ml cold brew concentrate

Step-by-Step Brewing Method

We recommend using a French press for ease and consistency.

  1. Add coffee and water
    Combine ground coffee and cold water in your French press. Stir gently to ensure all grounds are saturated.
  2. Cover and steep
    Place the lid on (but don’t plunge). Refrigerate and let it brew for at least 16 hours.
  3. Filter the brew
    Press the plunger down slowly. Alternatively, pour through a paper filter or fine mesh sieve.
  4. Decant and store
    Transfer your cold brew concentrate into a clean bottle or jar. Store in the fridge for up to 7 days.

How to Serve Cold Brew

Cold brew is a concentrate, so it’s best diluted before drinking. Here’s a simple serving suggestion:

  • 30ml cold brew concentrate
  • 120ml cold water or milk of choice
  • Serve over ice and enjoy!

You can also use cold brew as a base for:

Tips for Better Cold Brew

  • Use filtered water for a brew with the most clarity and cleanest taste, or consider crafting some specialty coffee brewing water with Aquacode.
  • Experiment with brew time (12–18 hours) to find your preferred strength. Fancy it a little stronger? Leave it to steep for longer. Want to lower the extraction to perhaps highlight some of the lighter, more subtle flavour notes? Try a shorter brew time.
  • Try single-origin coffees for unique flavour profiles.
  • Always store your finished product in a sealed container to preserve freshness.

Explore More

Coffees we think you'll really enjoy cold brewing


We have a wide range of single origin coffees and blends and the truth is, they'll all make tasty cold brew! But below are a few we think will really tick the right cold brewing boxes.

Midori Fujimoto Brewing A Chemex. Rectangle Crop.
Midori Fujimoto Brewing A Chemex. Square Crop.

Let's brew this!

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