consumer-grade modified atmosphere storage?

Question

I hope this is the best forum to ask this question on:

Where we live, mould is basically inevitable on anything that we put into storage for more than a few weeks, esp. on sensitive things like shoes. Air-tight containers with as little oxygen as possible (can't call it vacuum... :)) help for clean clothes but it's of course near impossible to get leather to the same level of through-and-through cleanness.

Which led me to wonder: what if instead of storing things under some approximation of vacuum, we store under regular atmospheric pressure but with the air replaced by an inert gas that won't allow anything aerobic to grow? You can get your tyres inflated with nitrogen, so even if I've never seen a workshop where they offer the service I assume that means that it doesn't require industrial or research lab working conditions.

I haven't yet found anything suggesting that there exist consumer grade storage solutions of a kind where you stuff things in a container (rigid or not), connect it to your nitrogen container and "flush out" the air from the box to replace it with the inert gas before sealing it.

Would such a system be conceivable, and would it indeed help with preservation?

Answer 1

Air tight buckets and dry ice are used by some preppers to store food in oxygen free environments (as a bonus, it also kills any bugs hiding in the grain/beans). As long as you make sure that you don't end up with a crust of water ice on the outside you should be able to do the same to keep your items dry and mold free assuming they've been thoroughly cleaned before being put into storage.

What you do is to put a layer of dry ice in the bottom of the bucket, put whatever you want to store on top and then put the lid on almost but not quite tight enough to fully seal the bucket. Leaving a minimum opening is needed to prevent pressure building up from rupturing the bucket as the ice sublimates. After the initial partial closing you monitor the temperature of the bottom of the bucket, and seal the kid down when it's no longer extremely cold. If you're doing a number of containers at once you'll want to make sure your work space is well ventilated.

A 6 gallon storage bucket contains 1.5 cubic feet of volume, and you want enough CO2 to fill the volume about twice over to be confident you've displaced all the existing air inside. A pound of dry ice will produce 8.3 cubic feet of CO2. For something like shoes that have a lot of empty space it's probably best to assume the volume if what you're storing in the bucket is negligible for planning purposes, so you'd need about 5.8 ounces per bucket. At around a dollar/pound it's cheap enough that unless you're storing a lot of stuff at once you'll probably spend more on the gas going to get it than anything else.

Ultimately though, while more practical than Ed Beal's discussion about nitrogen filled warehouses, dehumidifying is still probably the more practical option.

My source for the above was: http://www.thefoodguys.com/dryice.html

Answer 2

I know some Fruit producers use a nitrogen atmosphere to keep the fruit in a dormant state then at thanksgiving they sell as fresh it has not been frozen. The warehouse/cooler is completely sealed and flooded with nitrogen gas then a small amount is constantly injected to keep air from creeping in as air is ~ 79% nitrogen and ~%20.7 Oxygen with other trace gasses, so yes it can be done

I think it may be less expensive to de humidify.

We keep several Dri-Z-air moisture collectors in our motorhome they keep the moisture low enough to prevent mold, if we do not have 2-3 of these full of the crystals and drain them every month or so we have mold growing in the motorhome within a few weeks of using it (we live in Oregon so mold is a fact of life here). I think there are other brands I just remember this one because we have used it for years and purchase the crystals in bulk when they are on sale.