It’s that time of year, when some of you convert from hot to iced coffee. Here at The Lab, there are 3 options to meet your seasonal needs: Cold Press (which you are probably most accustomed to), our Yama slow-drip tower and Japanese Iced method. I’d like to take a moment to walk you through Japanese Iced because it’s one of the cleanest, most crisp versions of iced coffee and is the only one that can be brewed on-demand.
But before we talk about what makes iced coffee work, let’s cover how not to do it:
Don’t: Brew hot coffee and then stick it in the fridge (or let it sit out) to cool off. Why is that an issue? Because before the coffee is cold and stable, oxidation occurs. Oxidation is the process of oxygen pulling away electrons from another molecule. These molecules, with an uneven number of electrons, become unstable and begin reacting with other molecules around them. When this happens, the delicate notes of your specialty coffee are lost.
To prevent this you can perform the extraction in a cold environment (e.g. cold press or slow-drip), but it requires considerably more time (12-24hrs) to get the extraction. What do you do when you want an on-demand cup but want it cold?
Instead: Extract hot while dripping onto ice cubes. This method cools the coffee quickest. Having said that, you may be wondering, how can you just add ice without overly diluting the cup? To find an answer to this, go back to one of our earlier posts Extraction vs Concentration.
Let’s say you want a 16oz cup of iced coffee. You’ll follow your brewing parameters for a 12oz cup, but instead of pouring the full 400ml of water, start by replacing 1/3 of it with ice (130g) and just pour over 266ml. Once that has finished brewing, pour it over another 130g of ice. This is called Japanese Iced method, and it’s one of your best bets for the summer.
This substitution of 1/3 ice to start can be done with any of your favorite pour-over methods including your V60 (pictured), Kalita Wave or Chemex. Now you are on your way to delicious, iced-coffee that can be ready in minutes.
Remember, Japanese Iced coffee is always one option for our pour-overs when you come to The Lab. With it, you’ll also have the choice of one of four single-origin coffees from our current guest roaster.