Decided that I wanted to try my hand at making black garlic… and since stuffing my oven with garlic and leaving it there for over a month seems a tad excessive, I had to look for other options, and this heated cupboard / incubator was the solution I came up with. My cupboard uses a 150w ceramic heat emitter as its heating source, but a 50w emitter could get the cupboard to 70 Celsius with no problem, didn’t try to take it any higher.
To be suitable for the production of black garlic the cupboard needs to be able to do two things:
1: Maintain a temperature of 60 Celsius for 40 days straight.
2: Keep the garlic from drying out during these 40 days.
3: Allow the garlic to dry once the 40 days are over.
This is achieved by using an IKEA “Bestå” cupboard as an enclosure for the ceramic heat emitter and garlic – the (mostly hollow) wood of the cupboard provides some amount of isolation, and adding aluminum foil to reflect the infrared radiations helps keep the heat inside. While inside the cupboard the garlic are kept in closed IKEA “Korken” jars which prevent the garlic from drying out before it is time – and once it is time the jars are opened and the cupboard ventilation system is activated, which will dry the garlic.
So, can this cupboard only be used to make black garlic? No – if your thermostat allows it you can set it to some other temperature between room temperature and 70 Celsius and use it for other cooking purposes or even a home microbiology project.
Do note that this project uses mains electricity so do not attempt to build it unless you know what you are doing – I am not liable for any product failure, injury or damage resulting from building (or failing to build) the project or using the finished cupboard.
I have included price estimates based on my local prices – depending on where you live and what is available you may do better or worse. If local stores fail you then it should be possible to source the non-IKEA materials from eBay.
List of IKEA materials
1 x “Bestå”, 60cm x 40cm x 64cm (cupboard with two shelves) [€33]
2 x ”Attest” (handles) [€4]
2 x ”Bestå Vara”, 60cm x 64cm (doors) [€27]
1 x “Koppla” (3 outlet power strip) [€2]
16 x “Korken”, 1l (jar with lid) [€32]
1 x thermostat with temperature probe [€16]
2 x ON/OFF switches [€1]
1 x ceramic socket bulb holder [€2]
1 x 150w ceramic heat emitter [€8]
1 x DC power supply [€3]
2 x fan [€6]
2 x aluminium cover for fan [€3]
Heat resistant wire cable [cheap]
Heat shrink tube [cheap]
Self adhesive rubber door seal [€3]
Thick aluminium foil [€6]
Suitable lock(s) [€9]
Do not assemble the “Bestå” cupboard right away, you will want to make some modifications to some of the parts. Start with one of the sides of the cupboard.
Make holes for the fans and switches, then insert the switches,
and attach the fans. Make sure that the switches are accessible from the outside, and that the fans are located on what will be the inside of the cupboard, align the fans so that one of them blows air into the cupboard and the other one blows air out of the cupboard.
Attach the aluminium fan covers to the outside.
Assemble the ”Bestå” cupboard, but do not attach the shelves or doors. Drill holes for the wires in the back of the cupboard. Connect wires to the switches, cut the wire to “Koppla”, 40 cm from the power outlets. Feed the wires and the temperature probe through the holes. Make a hole near the top of the backside and feed the temperature probe back into the cupboard through this hole. Connect the thermostat and DC power supply to “Koppla”, feed the wire from the DC power supply though the hole in the back. Attach the “Attest” handles to the sides of the cupboard.
Take one of the shelves and drill holes for the wires to the ceramic socket – then connect the wires to the socket, feed them through the holes and fasten the socket to the shelf. Place the shelf in the cupboard and feed the wires though the hole in the back, then screw in the ceramic heat emitter.
Now it is time to connect the wires – do it so that one of the switches control the fans and the other one controls the heat emitter.
Drill a hole for the remaining wire from ”Koppla” in one of the “Bestå Vara” doors, feed this wire through the hole, then connect it to the part of the wire that is still attached to the “Koppla” power outlets. Attach the door to the backside of the cupboard using screws – this door is not meant to be opened, it is supposed to hide the wiring and to provide extra insulation.
Drill holes in the second shelf and place it in the cupboard – the holes are there to allow the two fans to ventilate both of the cupboard’s storage compartments.
Attach the second door as per the IKEA manual.
Attach the self adhesive rubber door seal – depending on which locking mechanism you have opted for you may need to install it before you sort the seal.
Test that your locking mechanism works and that the seal is tight.
Cover the insideof the cupboard including the door (but not the shelves, it will make them more difficult to clean) with the aluminium foil.
Fill one of the ”Korken” jars with water, submerge the temperature probe in the water and close the lid. The water will mimic the inside of the garlic.
You can now fill the remaining 15 ”Korken” with garlic and activate your cupboard. Have fun!
If you don’t use all your “Korken” jars for garlic then you can fill the remaining ones with water, close them and place them in the cupboard along with the ones containing garlic, the water will function as a reservoir for the heat. The detailed recipe for black garlic will be available at notsimply.net once I have had time to run the cupboard for 40 days and a few days more.
Is there room for improvement? Surely. But this was the best I could throw together at a moment’s notice with the materials I had at hand and what I could get in the local IKEA.