Oxygen absorbers .. test

[Ian]

I played with the 'Hothands' packs a few years ago. I have (don't ask why) a huge measuring cylinder of two litres capacity. I straightened a coat hanger and bent a clip in one end. Opened a 'Hothands', quickly attached it to the coat hanger end, dropped it into the measuring cylinder and inverted the lot over a full sink of water, the 'Hothands' being held out of the water at the bottom of the inverted cylinder by the straight wire.

The water slowly advanced up the cylinder until it stopped at 1.6 litre mark (upside down remember).

I repeated and repeated and repeated this eighteen times with freshened air until it stopped by which time the single pack of 'Hothands' had absorbed just over seven litres of oxygen.

Skippy. If your analyser is the fuel cell type you can remove the gas deflector from the face of the cell and just drop it in the bag with the absorber and close, not seal, the bag around the cable. The Oxygen level will slowly drop over an hour or two and thermal movement and diffusion will let the cell 'see' the gas in the bag well enough. If the analyser is a Servomex type you will need a needle on a hose to sample the bag and a pump to suck the gas over the analyser. Probably not worth it.

People who put food into environment controlled bags E.G. the lettuce at your supermarket have hand-held samplers with a sharp probe and an inbuilt flow pump just for that job.

http://www.cambridge-sensotec.co.uk/p-O ... 5/Software

[Ian]

Barrier bags.

Here is one:

http://standuppouches.co.uk/High_Barrier_Bags.htm

But there are dozens of manufacturers in the UK. Just Google "High barrier bags" for example. Embossed types are made for home vacuum sealing.

A barrier bag has a number of layers, a tough outer, an impermeable middle, say nylon or in the case of Mylar, a metal film, usually aluminium, and a melt-able inner such as polythene so the bag can be sealed.

The barrier, aluminium or nylon or whatever, slows the oxygen diffusing in through the bag. The oxygen absorber takes up the oxygen there to start with and mops up whatever slowly diffuses through during storage. That is why the absorber should have excess capacity above the starting bag volume. When the absorber is exhausted the oxygen that then diffuses in starts to degrade the food by, wait for it, oxydisation. The free oxygen also lets most of the nasty bugs start to grow.

Food degrades in a number of ways including bugs that don't need (and prefer not to have) oxygen around. So storing in an Oxygen-less atmosphere is not the whole answer.

[skippy]

Thanks Ian
Im aware of how oxy absorbers work ..
I was however interested in the efficiencies of the "hot hands" type as compared to the proprietry oxy absorbers for food storage.
You have given me a great idea tho ... so I will give it a go when I have a minute and let everyone know how it goes

Skips

[the-gnole]

Sorry if we misunderstood where you were with O2 absorbers

By the looks of it they are very efficient, maybe overly so in most domestic situations