temperature controller

We finally got around to making a batch of tempeh. In order to maintain the proper temperature for incubating it in a cooler, we came up with this control device made from a spare thermostat, a light bulb, and a 120V to 24V doorbell transformer (thanks Jack!). All of which are scrap parts that can be attained inexpensively.

Most home heating and cooling system thermostats require 24V, so this makes the transformer necessary. At 24V, a 60W incandescent lamp will use 6W, which is close to the 7W light bulb recommended by the tempeh culture instructions.

The thermostat we used only goes up to 82°F, whereas incubation is supposed to be in the 85-90°F range, but hopefully it works out! We also added some thermal mass (water) to the container to moderate the temperature swings.

Off the shelf options include:

reptile terrarium temperature controller (60-105°F)

brewing temperature contoller (20-80°F)

Or get the deluxe Fridge/Fermenter Controller from Holy Scrap Hot Springs when it is ready!

The reptile controller would not be good for controlling refrigeration as it isn't designed with the proper hysteresis to prevent wear and tear on the compressor. However, you could get away with using a peltier/thermoelectric refrigerator for cooling.

Update: The 6W wasn't enough to keep the temperature up, so we switched to a 75W lamp (9W) plus 11-16W of uncontrolled Christmas lights, which let us get up to 90°F.

hard apple cider

Our apartment is a-bubbling with the sounds of fermentation! A while ago, organic apple cider was on sale at the grocery store--packaged in big glass gallon jugs, perfect for brewing hard apple cider. I finally got around to starting it the other day.

I loosely followed this recipe. Usually we use honey when making wine/mead, but I decided to try sugar this time. In my opinion, everything but the sugar and the yeast is optional: I omitted the pectic enzyme and yeast energizer because those didn't come with our garage sale'd brewing kit. I did use the optional campden tablet--it kills any wild strains of yeast and reduces the chance of having potentially good or bad "off flavors." Campden tablets can also be used to de-chlorinate tap water. If you do use a campden tablet or other sulphite, it may be a good idea to wait 24 hours before pitching the yeast.

I poured some cider out of each jug so that they didn't foam up into the airlock, but it happened anyway, so I had to stir down the bubbles a couple times. I'm going to try ice distilling one jug into applejack and maybe make the other one a sweet hard cider with bubbles.

Oh, leave a comment if you have a good recipe for ginger beer or root beet--I'd love to try those out. Maybe I'll try making the famous D 'n' B--Dandelion and Burdock--there sure is a surplus of those two plants! I could go for a cold crisp Cel-Ray too. So much to do--let the fermentation begin!