h a l f b a k e r yI think, therefore I am thinking.
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So why do Fritos have a shelf life measured in years, even though they go stale within minutes of opening the bag? One of the answers is that the packaging is most likely filled with inert nitrogen instead of air. Food processors have long known that inert gas inhibits microbes as well as retards the
oxidation of oils (which makes things taste stale and rancid). So why not a consumer version that will keep your fresh food fresher? A small flow of nitrogen through the fridge would help a lot, and could probably be extracted from the atmosphere using the same process that home 02 generators use. Another approach might be CO2: because it's heavier than air, it would not flow out of a top-opening cooler every time you opened the door.
A small version for wine
http://www.wineeduc...access/dispose.html
[rmutt, Jan 18 2001]
One way to generate 02
http://jazz.nist.go...ctNumber=95-01-0178
Uses solid electrolyte. Depending on efficiency, what's left over is mostly N2 and inert gases... [rmutt, Jan 18 2001]
[link]
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What do home O2 generators use? |
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The other reason packaged foods
stay fresh is that they're packed
without any microorganisms. Once
you open it, the beasties get in,
and there are plenty of anaerobic
beasties. |
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Also, some of it has to do with
water vapor; once you open the
bag, the Fritos start drying out. |
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(Not to say that this wouldn't
have some benefit, of course.) |
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I don't know about the home 02 generators, but I would think that they would work by putting electric current through a mixture of water and an electrolyte. The water separates into H2 and O2, you can collect the O2 and burn off the H2 in the atmospheric O2 to get water again. The net effect is to take the O2 and collect it.... at least thats how I would build the thing. The problem with this is that I'm not sure you could get full combustion of the H2 to sufficiently get the O2 out of the fridge, and H2 gas is *not* inert. |
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who said anything about H2 gas, but thats "heavy" water and is rare. normal water when split would give you 2H and O2, NOT H2. |
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err, i mean, heavy water is, if i remember correctly, a hydrogen proton with 2 or 3 electrons, the type used in the older, (and the newer?) H-Bombs. Badoingdoing is right, hydrogen is not inert. |
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How about a fridge filled with fluorine? |
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Kender: Free Hydrogen doesn't stay monatomic long. Splitting water gives you 2H2 and O2. |
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True, mwburden. I believe what badoingdoing said about electrolytes. Our chemistry teacher did this experiment in class (save for the burning of H2 gas), but yes, you do have to have some form of electrolyte to facilitate the movement of ions 'n' charge 'n' whatnot. I think we used KNO3 or something like that... |
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Use the dry ice :-) (still was seeing them in some of the supermarkets) |
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On the other hand, I really like the idea of Nitrogen Fridge. Someone has to do it. |
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