On Feb 23, 10:03*pm, "Nonny" wrote:
I wonder why some company doesn't begin to sell compressed
nitrogen gas in spray cans, complete with a tube as found on many
lubricant cans. *For foods, a blast of Nitrogen into a zip lock
baggie would help keep food from oxidizing, while a blast into a
paint can before resealing might lengthen the storage life of the
paint.

Am I wrong in my assumptions that it would do this?

snip

Technically you are correct. Practically, the spray cans are pressure
limited (70PSI or some such?) so the gas volume is gone in one blast.
Liquid propellants are used to produce longer lasting operating
pressure for spray products, various Freons, propane among others.
Using crude arithmetic, a 2.5" x 6" spay can at 9 cubic inches will
hold about 45 cubic inches of gas at STP given 70 PSI initially. So
maybe a half dozen Ziplocks might be serviced. Not too good a return
on your expenditure.
Figure out a way to keep nitrogen pellets around at -200 degrees C and
you could have a neat product.

Joe