I’m building a dry curing chamber out of a fridge – for fermented sausages and drying cured meats. This means I can make salami, guanciale, coppa and all the other really good stuff.
When you’re hanging meats to dry them (prosciutto, for example) you need the relative humidity to be about 70%RH, and the temperature in the region of 12-15C, warmer and wetter than most fridges are prepared to run, so you need some additional equipment to maintain these parameters. We don’t have ideal conditions in the UK to do this without a little gadgetry.
I won’t go over all the ins and outs of how to do this here – these guys have done it all before and are the authority on it as far as I can see:
Look at all that beautiful stuff they make. mmmmm.
Anyway, I bought a large fridge, here it is:
My soon to be Curing fridge
Should have enough room in there!
I also bought a reptile vivarium controller which monitors and controls temperature and humidity, and an ultrasonic humidifier. I plugged all this in to see how it would work without anything sausagey hanging in there. I set the temperature to 13C, and the variance to 2C. This means that the fridge compressor starts when the temperature gets up to 15C, and stops cooling when it hits 11C. Simple enough. But temperature control is the easy part.
Controlling relative humidity is far more tricky. When running empty, the humidity in the chamber was all over the place, going from too high, to far too low. Hardly ideal, and would have ended up ruining quite a lot of potentially tasty meat.
So I made a sacrificial batch of Mexican style chorizo to test out the chamber’s drying capabilities. This cold-smoked chorizo only needed to hang for about a week, long enough for me to work out how well / terribly it might behave.
I hung up the sausages and began monitoring. They hung in there for a week and by that time they’d lost roughly 20% weight. But the humidity was still all over the place so for things which need much longer drying times this might not end well.
Here they are after being hung – I’ll make another post about how I made them at some point.
Cold smoked chorizo after hanging
But I need more flexibility and control.
I was chatting all this through with my friend Spandex – (he is both tall and wise) – and he said, “Someone must have done this with Arduino before”. I’d heard of Arduino before but never had experience with home electronics projects (other than building PCs), and the thought of wiring up mains appliances to relays is frankly pretty terrifying. He makes a lot of cool modular synth stuff so it’s right up his street.
So we hatched a plan to build a “sausageBot” – an Arduino-based controller which will monitor everything via sensors, and control all the equipment through relays. Spandex will be doing all the wiring and soldering and I’ll be asking daft questions and thinking about meat.
In return I have offered to pay him in cured meats. What a winner.
Here are a couple of mock-ups of how the case for sausageBot might look once finished:
Enclosure mockup – front
Enclosure mockup – top
last night we started to build the innards.
We went for a “let’s put something together and see what happens” approach. We’ve got a basic layout on breadboard, with the arduino reading temperature and humidity from the sensor, and we’ve also wired up the circuit for the first relay. Exciting stuff!
Sausagebot breadboard test
It’s obviously very early days but exciting nonetheless. Will post more progress when there’s some to show 🙂