wrote:

> > Ever wonder how food sealed in metal cans is
> > sterilized without exploding? They do it in large
> > pressure cookers (called "retorts").
> >
> And it's before they're sealed, by the way.

You don't know what you're talking about.
The cans are sealed first, then heat-sterilized
in a retort.

http://www.simplot.com.au/Hosting/co...+facts.canning

Once cans are sealed they must be processed as soon
as possible. The usual heat transfer fluids a
saturated steam
water
steam - air mixture

http://www.mcc.org/getinv/canning/recipe.html

Scoop out as much juice as possible and save in the
broth vat (to be canned later). Scoop meat into
28 oz cans; press meat tightly into the can. Seal the
cans with a sealing unit. Cook for 2 hours in a retort
steam cooker at 242 degrees. Cool cans in water
bath for 30 minutes. Remove from water bath, wash
grease from can and apply label with glue.

http://www.austehc.unimelb.edu.au/tia/084.html

At first the sanitary cans were processed in boiling
water baths, i.e., at 100oC (212°F) or in brine baths
at higher temperatures, as had been done since
Stefan Goldner introduced them in 1841. At these
higher temperatures, however, the lighter tinplate
tended to explode but the steam pressure in a retort
prevented this and it was not long before retorting
became general.