Avoid Watery Iced Coffee! The Ice Bath Method


It’s getting seriously hot in Japan these days. In this season, I want some good iced coffee.

How do you prepare your iced coffee?

By the way, did you know that iced coffee originated in Japan? I actually didn’t know, until I got into coffee brewing.

It’s just such a normal way to consume coffee in Japan that I never stopped to think it wasn’t in different parts of the world.

I digressed, today I would like to share with you my personal favorite way of preparing iced coffee, which I will refer to as the ice bath method.

As the name suggests, the ice bath method is a way of preparing iced coffee by brewing a normal hot cup of coffee, then quickly cooling it down by placing the entire cup into an ice bath.

It’s pretty simple, but let’s just quickly run over a bit more detail about how to make it, and the good and bad points of this method.

I believe this method makes the best tasting iced coffee, but the down side is that it takes a bit of work.

How to prepare

It’s kind of all in the name, so I will keep it quick.

Prepare your normal hot coffee in any method you like. I suggest a pour over, but an immersion brew or even an americano will work.

Pour this in a glass or cup, preferably in something with thin walls. (Do NOT use double walled cups)

Fill a bigger container with cold water and a lot of ice cubes, and place the glass with the hot coffee inside.

This is it!

That may have been a bit too short. Let me just add one important tip.

If you just leave the cup sitting, it will take a very long time for the coffee to cool down. So get a spoon and gently stir the coffee.

This will ensure the the hot parts of the coffee get a chance to touch the cold sides of the cup, greatly speeding up the process.

It’s obvious that this will cool your coffee, but you may be worried that it might not get cold enough.

But be rest assured, if you stir for like 10min (!!), the coffee will get to about 6℃, which is about the temperature of your fridge.

One last point, make sure you do NOT put ice cubes directly in the coffee!

Pros and Cons

There are a couple of ways to make iced coffee.

  • Throw some ice cubes in the coffee
  • Cold brew : brew with cold water from the beginning. takes a very long time
  • Cool a hot cup of coffee in the fridge

The main benefit of the ice bath method is that you get to keep all the depth and complexity of a normal hot coffee.

If you directly put some ice in your hot coffee to cool it down, it will of course cool it down much faster than the ice bath method. But your coffee will get severely watered down. To compensate for this, usually you will brew your coffee at a stronger ratio. But this is not always possible, and you will not get the best extraction.

Also, if you have ice cubes melting in the coffee, the coffee will keep diluting. You will only have a short window of time to enjoy your coffee at the right temperature and strength.

Cold brews should be considered as quite a different drink. The using cold water for extraction doesn’t just slow down the extraction. It affects what kind of stuff you can extract from your coffee beans. A pour over and cold brew will not taste the same, even if they were the same temperature.

If you like the taste of cold brew, by all means go for it!

I personally just prefer the taste of pour overs, which is were the ice bath method shines.

Cooling it in the fridge also will work the same way, but it will take hours. And the more time that passes, the more oxidation is going to occur.

(If you want to do it this way, try to cover your coffee to reduce air contact)

So is the ice bath method the best way?

Unfortunately I can’t say that…

The reason being, it’s very tedious. Who wants to stir their coffee for 10min?!

But it tastes the best, in my opinion.

Difficult decision…

Please try it out when you have a bit of time to spare.

If you like iced coffee, you may also be interested in the aerocano method.