Cold Brew: Ubiquitous, Hyped, and Pretty Darn Tasty
If you're drinking Specialty coffee in America in 2017, you'll have noticed that "Cold Brew" is absolutely everywhere you look: in grocery stores, on tap, at your favorite coffeeshop. It's a monumental trend and it's big business. But what's so special about it?
It's just another brew method, like espresso, French press, or pourover. But unlike those methods, cold brew uses tepid water to extract coffee flavor from the grounds. Lukewarm water is a less effective solvent than hot, so the grounds have to sit for much, much longer than hot brewing--between twelve and twenty-four hours.
Cold-brewed coffee has less acid than regular--67% less, according to Toddy, although I would mention that Toddy's recipe suggests quite a weak dilution, so if you want a really tasty cold brew that's less dilute, I'd bet it's more like a third less.
This lack of acid makes cold brew taste really different from hot-brewed coffee. It's sweeter and milder. This is, to me, just as much a drawback as it is a boon. Without hot extraction, a lot of the organic acids that give coffee its various flavors stay in the grounds. This is why I would not recommend cold brew for every coffee. Sometimes you want to taste everything that's in the bean.
Nevertheless, cold brew is uniquely easy to drink. It's almost like drinking coffee candy, even without sugar.
There are a lot of really mediocre or even terrible cold brews commercially available in bottles, cans, or cartons. I find most of them taste weak and oxidized. If you've only ever had cold brew prepared well in advance by someone else, I encourage you to try brewing your own. It's much, much better.
Select your coffee. Received wisdom dictates that you should use a light-to-medium-roasted bright American coffee, like a Colombia or Peru, because these coffees have enough acidity that they don't taste dull when cold brewed. My advice is to use any fresh coffee you like, but maybe avoid very dark roasts, as I do find that these can be dull and too roasty when cold brewed. Try our Guatemala Finca Palmira or our OFT Sumatra Kokowagayo, my current favorites for this brew method.
I have a home Toddy brewing system, which is fairly convenient and quite tasty, and is worth buying if you really like cold brew. But you can really use any two containers (one to brew and one to serve) and a filter to separate the grounds after its been sitting. Or just do it in a French press and plunge it.
You'll want to use a full pound for a 56-ounce Toddy. Adjust your recipe based on that ratio of 1 parts coffee to 3.5 parts water. Grind it coarse, as for French press. Like Kosher salt, more or less. Using finer coffee clogs the filter and usually tastes a bit overextracted (bitter).
Pour a bit of water into the bottom of the Toddy, and then dump half your coffee in. Slowly pour a couple more cups of water in, wetting as much of the ground coffee as you can. Repeat until all the coffee is in, then fill to the top with water. Now you can push the grounds down into the water, but you really don't want to agitate the grounds too much.
Put a plate on top and let that bad boy sit at least overnight (I prefer closer to twenty-four hours). Now filter the grounds out and you have a cold brew concentrate! Toddy says you can dilute this concentrate with 2 or 3 parts water. I say, no, you can't. 1:1 tastes really good and can be served over ice. Any more water than that is pretty weak. This is what makes so many commercially available cold brews so mediocre.
Another claim is that cold brew lasts up to two weeks in the fridge in an airtight container. Again, I'm going to say: not for best flavor, it can't. Drink it within a week.
You'll probably find this very easy to do, as coffee brewed suing the above guidelines is going to be absolutely freaking delicious.