How I Brew Coffee with my Chemex

Condensed Process for Future Reference

16:1 ratio
42g of coffee beans
#9 grind setting on Virtuoso
197degF water
~80g of water for bloom 45s
fill to 200g, stir
slow pour to 670g
~5 mins brew time

Introduction

I really like coffee. It has been an acquired taste. When I was younger I always turned my nose up at the stuff. In my family, it had always been a ritual to share the hot dark liquid with each other. Mom with two milk one sugar, Grandma took 3 milk, 3 sugar. Grandpa only took a little milk, one sugar. I suppose I was destined to eventually love the stuff. It was in my 20s that coffee really came into its own for me. For me starting out in IT there were a lot of late nights and early mornings. In those early mornings, I eventually turned to coffee for some socialization and caffeination. When I started, I was an IT consultant in Toronto. I was on a team working downtown Toronto in a building with a Starbucks on the ground floor. My team lead and I would start the day by logging in to our computers in our cubicles, putting out whatever fires there were and then heading downstairs for a coffee and talk about the day. Eventually it became a bit of an impromptu team meeting - we'd socialize and then get on with our day.

My tastes have evolved from those early days of sipping on a Starbucks Grande Bold, and I find myself gravitating to lighter roasts. I spent a long time just buying coffee on the way to work through a drive thru, but eventually started brewing my own coffee. My gateway to better coffee was an Aeropress. It's a great little device for one cup. Grind up some beans, flip that bad boy upside down, fill, stir and inject a mug with deep golden goodness. Recently I purchased a Chemex. Now that I've been spending a lot of time working from home, I've perfected my process for brewing and thought I'd share for friends and anyone else that wants to try my process. I've adapted from a few different sources - YouTube, blog posts by some very technical coffee nerds, advice from my local coffee shop and the #coffee slack channel at work. So here goes - my guide to brewing in a Chemex.

Here's the Process

I should start by saying you'll want to adjust this process based on your beans, tastes, etc. but I think this is a good place to start.

My equipment:

I have a Bonavita Electric Gooseneck Kettle (BV382510V), a Baratza Virtuoso grinder, the Brewista Smart Scale II scale, a Chemex "Six Cub Classic" and an assortment of mugs.

The beans I use are from a local coffee shop - Cavan Coffee. They are an amazing crew and carefully select beans, roasting them to some pretty exacting standards. Now that we are all staying at home, they even deliver to my door!

I measure out around 42g of beans before grinding. Sometimes it ends up being a little more, I'm not aiming for the same cup every single time, so if it ends up being 44g one day, and 42.4g the next I'm ok with that.

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I pour the beans into my Virtuoso and grind at the "9" setting. Here's where you'll want to play around with your beans and the flavor you're looking for. For me, the 9 setting is fine enough to extract everything I want out of the beans and into my cup. You might want to experiment with finer or more course.

Next, using tap water I fill the kettle. We have reverse osmosis filters for drinking water here and originally I was making coffee with that. But the coffee nerds tell me that if you use water that has no minerals in it, some chemical processes essential to brewing a great cup of coffee won't happen. I am taking their word for it and using tap water.

The kettle is set to 197degF, a temperature my local coffee shop baristas recommended. I expect this is based on my elevation above sea level. I set it there and it works out great for me.

When I bought the Chemex, I bought the "natural" filters. I thought natural = better, right? Turns out there are some differences between these filters and the white ones. The first brew I made with this filter tasted... not optimal. After polling some folks I learned that the natural filters should be rinsed, so once the water gets over 100degF or so, I start rinsing the filter. I generally fill up the upper section of the chemex with the filter seated a couple of times, then empty it out. I'll fill it one last time and let the water drain through the filter and then dump the water out.

Next I put the chemex with the wet filter onto my scale, and hit Tare. Then I dump the grinds into the filter, looking to see what the final weight of grinds are. Depending on the bean there might be a difference between the finished grind and the original weight. It's no big deal really but more on this in a second.

Here comes the math. It's not super complicated there are really only two numbers to remember. Honestly, because we have a Google thingy on the counter I just ask google to do the math. The magic ratio is 16:1. For every 1g of coffee grind, you want to use 16g of water.

So in this case, I had 41g of coffee grinds so I wanted to go to somewhere around 650g of water (yes I used Google again). I brew in 3 stages. First is the "bloom". This is the word coffee nerds use for soaking the beans in hot water and starting chemical reactions. You want to use roughly 2X the amount of grinds to get the bloom going. I don't always hit the number exactly. So for 41g of coffee you want to add 80-ish g of water. I press tare on the scale, and them press the Time button to start a timer.

Now I start pouring, making sure I get all of the beans. Usually I try and start at the middle and pour in concentric circles until I get to the 80 some g. Once the beans are soaked I wait for 45 seconds or so. There would be a lot of bubbling.

Now for the controversial piece of the brewing process. This tip came to me from my local coffee shop. A lot of how-to blogs and YouTube vids with the Chemex will have you pour until your final weight. But then the grinds don't all get to participate at the same level. I pour until I get to around 200g, and then grab a small spoon to stir up the grinds. Specifically I try to get into the bottom of the filter and make sure all the grinds are stirred up. You'll see in the picture that even though I've already finished the bloom and poured in another 100+ grams, some of the grinds were still dry. I stir them up an swirl with the spoon until I'm satisfied the water and grinds are mixed.

Now for the fun part. The goal here is to get to the finish line. I'm trying to get the total weight on the scale to my final water weight - so in this case like 650g. The coffee nerds really recommend a long, slow pour. I'm not sure what difference this makes, but it is fun to try and see if you can add the rest of the water slowly enough that you don't need to stop. If you pour too quickly, you'll get to the top of the Chemex and have to wait until some of the water drains before you add more. If you do it really slowly, you can keep pouring in circles for 3-4 minutes without stopping.

What I usually end up with at the end is a filter with very light foam with fine bubbles.

Now, I wait.

Somewhere around 5-6 minutes - it really depends on how busy I am while I'm making the coffee - I take the Chemex, filter and all to the sink. I'll lift the filter directly out of the Chemex and put in the sink drain. There will still be water in the filter that will slowly drain out while I'm drinking my coffee. When I'm done, I come back and pick up the now dry filter and put it in the wet (compost) garbage.