Use citric acid crystals instead of lemon juice and it won't affect the
taste. I'm not sure the amount, but the recipe should give you that as an
option. I pressure can my tomatoes, without adding acid. If I was gonna
process them in a boiling water bath w/o adding any citric acid, I would
pick an old commercial canning variety like "Marglobe" or "Rutgers".

In other words, if my parents could do it, why can't I?


Several reasons, which interact somewhat. Grandma used the best methods
known at the time, and so should you. The USDA continually does research,
and processing methods evolve over time. Your parents also might have
processed their green beans in a boiling water bath for 3 1/2 hours. The
old methods also included boiling canned meats or vegetables (except
pickles, obviously) for 10 minutes before tasting them. Now nobody does
this, and the methods have adapted to be safe enough to eat the contents
right from the jars w/o boiling. (I'm not sure which is the cause and
which is the effect here.)

People start canning now without ever having been taught how to do it
properly, so the new recipes have an extra margin for error. Also our
society is so paranoid about germs and so quick to litigate any and
everything, I think that adds to the safety margin. I think they go
overboard with a few things, but that's just my opinion.

Best regards,
Bob
Ageed : an excellent explanation.
With the exception of a couple of low acid USDA varieties which are extremely
rare all tomatoes have about the same amount of acid, The differnce is in the
sugar content. Yellows and whites have consistently the higher sugar content,
My mother canned the all (open kettle) without any problems.