I recently started acquiring everything I need to be able to slant and propagate yeast. I’ve never used liquid yeast before, so the first order of business was building a stirplate to be able to step up slants and make starters.
Stuff you need
- A fan – Many people use 12v 120mm or 80mm computer fans
- 1 or 2 strong magnets. I used one from an old hard drive, and some epoxy to attach it to the fan
- 12v power supply (wall wart) Make sure it is at least 500mA, preferable 1A
- Project box – make sure it’s large enough to hold the fan + components. You can get a cheap tupperware box from somewhere, or you can go fancy and buy an electrical box from eBay or radio shack.
- For the speed controller:
- Potentiometer, 1k resistor, 1uF electrolytic capacitor, 0.1 uF ceramic capacitor, protoboard, LM317 voltage regulator
- You’ll also need some tools to assemble everything, f.e. soldering iron, drill, screws, glue and a few screws
Let’s start with the speed controller
I followed the instructions from here to arrange the components on the strip board. In retrospect I should probably have gone with a PWM speed controller in order to have greater flexibility with setting the speed. Maybe next time.
As for assembling everything in a project box, a picture is worth a thousand words:
Depending on what box you will pick your mileage may vary.
Next on my yeast propagation todo list
Before I’ll be able to make yeast slants I have a few more things I need:
- Buy a pressure cooker to sterilize everything, including yeast slants
- Buy some yeast to use. I’m thinking I want to do a wit beer, some kind of belgian trappist and more. There are no home brew stores in Iceland that sell liquid yeast, so I will have to order from abroad and cough up some cash for express shipping and cold packs