Free cold brewed coffee. Free!!

Yes, free!! But you're going to make it yourself. The good news is you're not going to have to spend any money on new equipment, if you're already brewing coffee that is. People often ask me what the best cold brewer device out there is. My answer is always 'What is a 'cold brewing device' for?' Apart from wasting money or looking pretty?

There are cold brewers that cost $30 when they're just a funnel with a hole in the bottom, or HUNDREDS of dollars just for looking fancy and coming from Japan. None of this makes sense to me. Cold-brewed coffee is just coffee that has been sitting in water for a while, which is then filtered to take out the gunk.

I mean it's so easy to make that it's offensive how people can charge US$5 for a bottle of it. No more!

What you will need to brew cold brewed coffee

What you will need: A jar, a grinder, scales, and coffee filters.

  1. A jar. I prefer Vegemite jars. If you know anything about Australia, you'll understand why. If you don't, then the short story is that Vegemite is a disgustingly salty spread that for some reason Australians idolise. If you don't have a Vegemite jar for some reason, any jar capable of holding say ~350mls of liquid is fine.
  2. A grinder. You probably have one of these already if you're reading this blog. I got started using a Hario Mini hand grinder, but you can use any form of electric burr grinder or hand grinder available.
  3. Scales. Any small set of scales capable of weighing down to 1g (or better, 0.1g) is fine.
  4. A filter. You can use a funnel with a paper coffee filter in it. Or you can use a cheesecloth (please, not one that has been recently used on cheese).

How to do brew cold brew coffee with super basic equipment

This is the fun part because it's a few steps that, when you really think about it, can be summarised in: Steep ground coffee in water for a few hours in the fridge, then filter it.

  1. Measure out 40g of coffee, and grind it coarse. By 'coarse' I mean you look at the grinds and they're about 0.8-1.0mm wide. What you'd usually use for a french press.
  2. Put it in the jar and add 200g of water. Stir it in once or twice.
  3. Let it sit for 8 hours in the fridge. This is the hard part, I know. If you can, during the 8 hours come by and give it a bit of a swirl to redistribute the grinds.
  4. Filter it using a coffee filter and a funnel, into a serving pot of some kind.
  5. Dilute roughly 50/50 with cold water (or more or less to taste), and serve.

There are a number of ways to skin the cat, but the above method works and is a great place to start.

Adjusting the taste

If it's too bitter, then grind a bit coarser and try again. If it's too sour/weak, then grind finer and try again. Personally, I like to simultaneously brew three batches with different grinds, to try to find the sweet spot then use that one for the next batch.

Additional pro tips

  • Use good water. Why are you messing around with tap water, unless you live in Switzerland or NYC, which has weirdly delicious tap water? Use mineral water, or at worst, mineralised purified water.
  • Make sure the jar is sealed well. Coffee absorbs other odours surprisingly well. In fact, people use it to deodorise fridges. You don't want your coffee to taste like whatever you have in the fridge be it yesterday's fish balls soup, fresh durian, etc.