Creating the Perfect Cold Brew, In 5 Easy Steps
2) Let the Air Out
For this step, you’ll start by pouring half of your water over half of your grounds in whatever container you’ll be using for storage (any big, re-sealable jar will do fine), and letting it sit for 30 to 60 seconds. “When you roast coffee you create a lot of carbon dioxide inside of the bean, and when you grind coffee and pour water on it, all of that wants to escape, like when you pop a bottle of champagne,” Lind explains. “So by grinding it, pouring water on half of it and giving it a few seconds, you give that carbon dioxide a chance to let out into the atmosphere, and you allow the water to completely saturate the grounds instead of having air pockets.”
Fresher beans give off more carbon dioxide and can use a little more time, but after about a minute, you can add the rest of your grounds and water into the mix.