"Deidzoeb" > wrote in message
...
> I've done some canning with pint and half pint jars. Haven't killed or
> sickened anyone yet. Recently a friend gave me a dozen quart size jars
> and I'd like to can some salsa in them. Is the jar size one of those
> aspects of canning recipes that can be unsafe to change?

Without adjusting the process time, yes.

> Should I look
> for a different salsa recipe that specifies quart jars in the end
> step? I really don't want to give anyone botulism for Xmas.
>

Your going to have to correct me if your favorite salsa recipie is
different, but most of them I've seen spec tomato chunks. In short,
the finished product has significantly sized chunks of tomato in
it. ANY of these recipies should be pressure canned regardless
of any acidification that the recipie may specify or regardless of
any boiling water canning that is specified. Tomatos are
now known to be borderline low-acid, and the problem is that
in a recipie where they survive intact, you can have regions within
the tomato chunk that the acidification hasn't penetrated.

There's a botulism story floating around on the Internet where
2 family members ended up in an Iron Lung for a week
while their systems recovered, and the health department
decanted and tested every one of their 50 quarts of spaghetti
sauce they had boiling water canned, and found botulism
toxin in only 3 of them. Their sauces had ground hamburger
in them. The thought was that the toxin was created in
meat chunks and migrated to the surrounding areas.

With pressure canning, the process times are generally very,
very long. Read the manual that came with your pressure canner.
It will spec times for classifications of foods, these should
always trump whatever the recipie specs.

The more important issue, though, is convenience of the
recipient. You may like eating salsa a lot and could maybe
eat up a quart jar in a week, around here we use salsa only
for dipping potato chips into, and a pint is a 6 month supply
for us.

This is why I do most of my jam canning in 1/2
pint jars. I have several jam varieties I can. If I put them in
pints, I would get tired of that variety before finishing off the
jar, so I would end up with multiple open jam jars in the
refrigerator.

> I realize the amount of air space or whatever you call it at top of
> jar might need to be different for quart jars than for pints. Is there
> a rule for that, or does it depend on exactly what kind of food you're
> processing?
>

I have found it really doesen't make much difference. I can applesauce
in quarts because when we open a quart of applesauce we eat it
within a couple days, and I just leave the same headspace as in 1/2
pint jars. However I do leave a lot more headspace in jars when I
can turkey soup in the pressure canner.

Ted