Air Drying Meat - Equipment

Air drying Fridge

Posts have been pretty scarce around here lately. It's not that I've not been doing things; just that I haven't got around to writing about them.

The redesign of my 'drying' fridge has taken up a lot of my time - mainly because I'm not very good when it comes to anything that involves DIY skills! However, it's up and running again and although it will need a further modification (to remove a large dehumidifier that's inside it), it's working well.

The major change has been to install digital rather than analogue controls; they're far more accurate. I've also installed two humidity controls so that I can set the humidifier and dehumidifier to run independently. Designing the control box was a kerfuffle, but with the help of my friendly neighbourhood electronics expert (a friend with his own electronic controls company), I have finally got my head 'around' relays and other such electronic gizmos. The controls are now also housed in a wooden box kindly made for me by a neighbour. It still needs a coat of paint but that can come later:

Drying fridge control box

It's seen here running at high temperature (23°C) and humidity (82%) during the fermentation stage of a Genoa type salami. I'll post the recipe and method when I see how they turn out.

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There are seven comments


Can you share what kind of PID Controllers your using for the humidity? All the ones I’ve seen with that capacity are quite expensive. Is the fridge self defrosting? The reason I ask is that if it is I’m surprised you would need a "dehumidifier". Really would appreciate some more details of you set up. Thank you!

marc, - 29-08-’10 14:20

Phil, first thing – great blog – helpful and interesting, thank you. Second thing – apologies in advance for a pretty detailed question!

After all your experimentation, I’m thinking of following your fridge & Forttex example – spring now having sprung, my cellar’s reached about 16 deg C, with RH down to 60%, so I think I need to go technical!

My shopping list is as follows: old fridge, Forttex controllers (1 x temp, 2 x RH), Bionaire ultrasonic humidifier, Conrad mini dehumidifer. Even with all that kit to move air inside the fridge, I assume I still need a fan to exchange air with outside? If so, what in your experience is the ideal air exchange rate to aim for?

Also, I assume that both machines can go happily on the floor of the fridge, with all 3 sensors about three quarters of the way up, by which time any dry air should have mixed pretty thoroughly with humid air? What has your experience been on this?

Thanks – and apologies it’s such a long question. Like Marc, I’d hugely appreciate any further info you can share!

Charles, - 13-04-’11 14:42


Sorry for the delay in replying.

I wouldn’t buy all those things to start with – find out first if they are necessary.

Where to start? Well firstly, let me say that a fridge is often not the easy option. As you have a cellar is there anyway of making it, or an area of it, cooler? If you can, life will be so much easier. A large space is far easier to control than a small one.

If not, then get a fridge – turn it to it’s warmest temperature setting and see what the temperature is. If you can get around 12°C you could be OK without a controller. If not, then get the controller. When you have it running at the temp you want, put some salami/meat into it and check the Relative Humidity, it may be OK without further intervention. The humidity will be completely different with meat in the fridge compared to when it is empty. If the RH is not as you want it, try a mound of salt in a pool of water in the bottom. This may be enough to sort it.

If you can’t get it right, monitor it to see whether it’s too high, too low, or both. If it’s only too high, or too low (not both) you should only need one hygrostat (humidistat). You only need two if it fluctuates between being too high and too low.

Say a prayer and hope that, if it’s either, that it’s too low – it’s easier to increase it than reduce it!

If you need to dehumidify, I would check that your mini dehumidifier will work. If it’s a Peltier element one then all the ones I’ve seen don’t work below 15°C.

As to air circulation, I have a number of coverable 1 inch holes in the side of my fridge, I have a very small computer fan in one, it’s only about 1 inch across and runs on a 9v transformer, so it runs at reduced power. However, I rarely use it. I also have a similar fan mounted on one of the shelves, again, it’s rarely used. Generally, with just one of the holes uncovered, I have sufficient air-flow.

I hope this helps – please email me and let me know how you get on.

Phil, (Email ) (URL) - 16-04-’11 14:33

My brother has a similar problem with his setup. He needs to dehumidify and we found one that works at a minimum temperature of 5 degrees celsius. It was a bit expensive though. Here is the link in case anybody is interested.
There is good information about it here

Roberto, - 06-05-’11 02:25

Thanks for the info Roberto.

Phil, (Email ) (URL) - 06-05-’11 16:06

I just thought I would put it out there in case someone else needs the info because I know, that like me, a lot of people come and read this blog and take a a lot of tips on how to build their own curing chamber thanks to your posts. I am thankful that you took and take the time to post stuff because it helps us all. In fact it helped me helping my brother build his and mine is nearly ready, will be today in fact.

Roberto, - 06-05-’11 17:22

Many thanks Roberto – I’m sure that people will find it of help.

Phil, (Email ) (URL) - 07-05-’11 16:06

I'm somewhat incapacitated at present so replies may take some time. Please post urgent enquiries at the forum.