I am definitely a coffee fanatic, and one of my recent home projects, has been making Kyoto style iced coffee. This process is a slow extraction of coffee using room temperature water that takes 10-14 hours. The thing that sets apart this style is that it brews coffee by introducing one drop of fresh water to the grounds at a time. The reservoir at the top has a nozzle that allows you to adjust the amount of water it releases; one drop every few seconds is the range I’m looking for. The machines used to make this style of coffee are usually imported from Japan and are functional works of art. This justifies the $300+ price tag of many of these machines. I love Kyoto style iced coffee; it’s smooth, naturally sweet and has a great mouthfeel, like bourbon. However, I don’t have $300 to burn and one of the few cafés that offers Kyoto style charges $5 a pop for an 8 oz. cup of the stuff, didn’t they hear about the recession? This is when I heard a voice say: “If you build it…”
So I did. I needed something that could release one drop of water slowly, at uniform increments of time and it had to be as cheap as possible. If I could make that happen, I could make the coffee happen. I looked around for different things that might get the job done but to no avail. That’s when I remembered my good old friend from chemistry class, the separatory funnel. Separatory funnels are used to separate liquids of differing densities by allowing them to first stratify, and then slowly funneling off the bottom layer one drop at a time, this is exactly what I needed.
Luckily for me, there is a science lab surplus not too far from my house, and I was off. The surplus store was worth visiting even if I didn’t find the funnel. There were so many cool things that I decided to stick around for an hour and relive some of childhood fun. Once playtime was over, I got the funnel and a lab stand; the damage, 55 bucks. I felt like a boss. Now that I had the most critical part of the setup, I was ready to create the rest of the rig using things I had around the house; cue the MacGyver theme. I needed a chamber to hold the coffee so I cut the bottom off of an extra condiment squirt bottle I had (these are useful for spritzing olive oil). Next was the container for collecting the finished coffee. The first and most obvious thing I thought to use was a Pyrex measuring cup. I ended up favoring the pitcher from my blender because the lid has a hole in the center and the squeeze bottle head fits perfectly through it. This meant that I would not have to fabricate housing for the bottle chamber. It was an epic day for lateral thinking. I set everything up, tuned the funnel to one drip per three seconds and I went to bed. I awoke to find my brew done; all that was needed was a few ice cubes.