How to Make Cold Brew (or Flash Chilled) Coffee


How to Make Cold Brew (or Flash Chilled) Coffee

  • Cold coffee can brew broken down into three main styles: cold brew, cold drip and flash or snap chilled.
  • Cold brew uses an immersion (steeping) method, usually 12 hrs in the fridge with coarser than usual grounds. We highly recommend starting with already cold (instead of room temp) water.
  • Cold drip uses ice/ice water to slowly drip over ground coffee. As soon as it's finished throw it in the fridge to minimise oxidisation.
  • Flash chilled (or snap chilled) coffee is where the fun is! For this we brew hot like usual but over ice - so the coffee cools immediately.
  • This style of cold coffee not only captures the origin character and fruit acids in a coffee (making it incredibly crisp and refreshing) but also minimises oxidisation.
  • To brew flash chill coffee break-up your brewing water into a 60/40 split between brewing (hot) water and ice (to chill after brewing).
  • You'll also need to grind finer to compensate for less solvent (water).

Transcript (Speaker: Adam Marley)

Hey guys. So, we're back with another tips and tricks. This one I'm inspired by the nice weather we're having today. I'm in the car at the moment, but it's beautiful and sunny out there. I think tomorrow's going to be 30. So yes, finally some nice weather. So, today I'd like to talk about cold brew coffee, very popular, obviously. In the last few years, it's exploded in popularity. But a confession I have to make is the standard cold brew coffee is not something that I've ever really enjoyed. I've found that it doesn't really capture the origin character of a coffee very well. It can also regularly taste oxidized. If you ever had cold brew that tastes like fridge, you're tasting that oxidization. But you can make cold coffee in a way where it's absolutely phenomenally delicious. And I'd like to point out, if you like cold brew, standard cold brew, that's great. That's awesome. You do you.

And you might not like this version. But I definitely encourage anyone who makes cold coffee at home to give this a shot because you might absolutely love it. It might change how you see cold brew coffee. So, this goes by a few different names. I think what's more popular at the moment, what's been going around a lot is Snap chilled coffee, which you may have encountered. And so it is what it sounds like. Instead of brewing coffee cold, what we do is we brew the coffee hot like we usually would, and then we snap chill it. We cool it down immediately, really quickly. The idea there being that we don't give the coffee a chance to oxidize, and we preserve the fruity, bright, interesting origin characters which were in that coffee.

So, the way to do it is pretty simple. It's nothing crazy. But ordinarily with cold brew coffee, and I guess we can talk about how to make cold brew coffee while we're talking just cold coffee in general. There's lots of different ways you can do that. Some people just brew coffee with room temperature water in a full immersion situation, like in a plunger. There's the devices you use specifically for it and just throw it in the fridge and then just leave it there for 12 hours. And with a coarser grind, you'd make some adjustments to take into account that extended contact time. If you do it that way, I would definitely recommend using water, which is already in the fridge. Don't start with room temperature water, put the water in the fridge beforehand, night before. Then make it that way and put it back in the fridge.

I find you'll get a crisper, more refreshing result that way with less oxidization as well. The other version, which everyone's seen the towers, cold drip coffee, if I've been saying cold drip, I mean cold brew. Because obviously that captures everything, but cold drip specifically is where you've got one of those towers, you can have a little one for home. You've got ground coffee, vessel in the bottom. And then you have ice water, which slowly drips through the coffee also works really well. Soon as it's finished, throw that in the fridge again, try and minimize oxidization. I personally don't think there's really a benefit to either of those over the other, except I like full immersion brewing in general a bit better. Getting back to snap chilled though where the fun happens, so this would be very similar to brewing a hot coffee like you would ordinarily at home.

There's a few differences. So what you would do is, and you can mess with these ratios a bit and find the sweet spot. What I tend to do is I'll make, say it's a pour-over or a French press. French press, it could work, but usually it'd be with a pour-over an AeroPress, you would do this, but you could probably make it work with any filter brewing method. But what you would do is take part of what would be your brewing water and instead make that ice in the bottom. So in the carafe or whatever you're going to be brewing into. So say for instance, I was going to be doing brew with a liter of water ordinarily. So let's just say pour over a liter. I mean, I wouldn't do a litter pour-over, but anyway, a liter of water and I'm going to do a pour-over.

I personally like to go for a 60/40 ratio. So I would take, in that situation, 40%. So 400 ml of the brewing water, and then that would become ice in the bottom chamber, whatever I'm brewing into. So if it was a pour-over, you'd have the cone, then you'd have your vessel underneath. So just put that ice straight in there. And so now you've with your brewing water, you've just left with 600 ml, 60%, and you can vary these around. Don't have to stick with that, but it's a good place to start, 60% brewing water. And then pretty much you'd brew your coffee the way you would ordinarily with a few adjustments. So I tend to use the same amount of coffee as I usually would. So if I was doing a standard filter brew, a percolation brew, as opposed to a full immersion brew, I would personally use 60 grams of coffee for every liter of water.

You can play with that anywhere between 55 and 70 is probably going to taste pretty great, but so I would start there. And then, so I've got 60 grams of coffee, however, because I've got a lot less hot water to brew with. We've turned so we've taken some of that water and instead replaced it with ice in the bottom, because we've got a lot less hot water, that hot water is our solvent. So because we've got a lot less of it, if we didn't change anything else we would under extract the coffee, because we've got a lot less solvent and the same amount of solutes, that we want to dissolve. And so to compensate for that, what we do is grind quite a bit finer. I can't say exactly how much finer, but it's going to have to be a bit of a trial and error situation.

But I would say in my personal experiences, it's probably going to be finer than you think. So for me at home, instead of doing a pour-over grind setting, I would probably do a French press or cupping grind setting, which should be substantially finer. And so by grinding finer, you increase the surface area, we're going to increase our extraction potential. And then hopefully mitigate the fact that we have less hot water solvent to do our extracting with. And so you'd have your pour-over cone with your coffee, your hot water and your kettle, ready to go, your ice in the bottom and then just brew it. The hot coffee is going to brew and then immediately hit the ice and cool down, hence the snap chilled and then leave you with something that's very refreshing. So the benefit of using hot water is we're still going to extract those fruity juicy, refreshing acids, which are in the... This is directed towards a light roast, single origin coffee. That is going to help your brain pick out the unique flavors which are in that coffee.

When we're tasting coffee, we might have aroma compounds, which are fruity in that brew. But if those fruits that we usually encounter when we're eating them fruits, which have some nice juicy acidity in sweetness and that brew doesn't have that same acidity in it, even though the aroma compounds are there, you won't taste them. Your brain is just going to voop, cut them out because your brain goes, "Hey, I've got these aroma compounds, but I know that that fruit usually has some acid with it. I'm not getting any acid. So obviously I'm not eating that fruit right now. It's a mistake." And I tend to find at least with a light roast, which is the best way to highlight origin characteristics in a single origin, which I guess really is the point. If you're buying a single origin, you want to experience those though experience those unique characteristics that each coffee has.

You get a need to have that acidity is still there for your brain to be able to notice those flavors, basically that make all those coffees interesting and unique and delicious. With cold brew, it's really hard to get those acids, that juiciness to come through and then adding the oxidization, just makes it even harder. And you shouldn't get any oxidization with this method. And so, that's basically the tip for this week is to, if you make cold coffee at home, give snap chilled coffee a try, feel free to throw any comments. If you've tried this, I want to know if you already brew this way at home, please let us know in the comments. If you've got any questions about ways to tweak things, what kind of coffees to use to make this the most enjoyable method, throw them in the comments.

I'm really keen to hear your thoughts. If you experiment with it and you don't like it and you prefer ordinary cold brew, let us know, please. I would say that this is perfect for nice warm weather. I actually find that ordinary cold brew, quite nice and winter. It's warm, it's rich, it's comforting, but this is perfect, snap chilled coffee is perfect for warm weather because honestly it's like drinking an ice cold juice or white wine or something like that on a hot day. Super refreshing, still have that origin character. It's a winner. Anyway. Thanks guys. I'll see you soon.