Previously I have been told that the need to acidify tomatoes before canning
was not dependent on the soil but on the variety and that the problem is
that many of the currently popular varities do not have enough acid of
This, then, begs the question of which varities DO supply sufficient
acidity. I am growing heirlooms this year and plan to continue
indefinitely. I would certainly be willing to plant varieties that
supported the end goal of not adding lemon juice but also not taking undue
chances with my family's health.
Does anyone know (or have a link for) high-acid tomato varieties?
Zone 8b (Detroit, MI)
I do not post my address to news groups.
I've never heard that tomatoes didn't have enough acid to justify open bath
canning. I've canned many different types (red only) and never gotten sick.
The only thing I've heard is that the yellow tomatoes are a LOWER acid than
red tomatoes. I think all tomatoes contain acid.
If you're still uncertain, why don't you contact Ball or Kerr and ask them?
These are two manufacturers of canning supplies and I'm sure they must have
some reference somewhere that indicates unsafe practices. Good luck and let
us know what you find.
Zone 7b - North Carolina
Many tomato varieties are now considered to have
insufficient acidity for safe water-bath canning. Because
of this, the USDA recommends that all acid (lemon juice
usually) be added to all tomatoes to be water-bath
This can be avoided by pressure-canning the tomatoes.
See 'The USDA Complete Guide to Home Canning', which says -
in part -
Acidification: To ensure safe acidity in whole, crushed, or
juiced tomatoes, add 2 tablespoons of bottled lemon juice or
1/2 teaspoon of citric acid per quart of tomatoes. For
pints, use 1 tablespoon bottled lemon juice or 1/4 teaspoon
citric acid. Acid can be added directly to the
jars before filling with product. Add sugar to offset acid
taste, if desired. Four tablespoons of a 5 percent acidity
vinegar per quart may be used instead of lemon juice or
citric acid. However, vinegar may cause undesirable flavor
Actually, the new Ball canning book I purchased is where I read that lemon
juice needs to be added as there is no guarantee that today's tomatoes
have enough acid. They made no reference to a particular type of tomato
but included all in their recommendation.
The canning tomatoes directions indicates hot water bath (Pages 24-25 with
drawings). The directions for canning tomatoes include "Add 2 tablespoons
of bottled lemon juice or 1/2 teaspoon citric acid to each quart jar." I
didn't like doing it as it seemed likely to affect the taste of the
tomatoes but I did it anyway . . . it was not noticeable in the canned
product. Even if it had been, it certainly would be worth keeping my
Ball Blue Book, Guide to Home Canning, Freezing & Dehydration, Copyright
1995, 1997, 1998, 1999.
For questions, call (800) 240-3340
BTW, it says nothing about adding salt (or anything else) to tomatoes when
dehydrating (Page 106).
Hope this helps.
Hot water bath referred to both, packed cold and packed hot, and then the
finished jars processed in a hot water bath for a specified period of
time. That would include such things as peaches/pears which are packed
cold and tomatoes/tomato juice which are packed hot or warm. There are,
of course, many other items processed in that manner. (It is referred to
in the Ball Blue Book as Boiling-Water Method with the one using pressure
referred to as Steam-Pressured Method. Both methods involve placing hot
or cold foods in the jars initially but require certain processing times
with no difference listed as to beginning temperature.)
Open kettle referred to cooking the ingredients in an open kettle (hence
the name) and then poured into jars hot and placing seals on the jars
immediately with the cooling causing the lids to seal. This was used for
things that were perceived as needing no further processing, such as
pickles, jams, etc. The sealant could be lids and rings
(pickles/jams/jelleies/etc.) or wax as in the case of jellies/jams.
Open kettle, as I understood and listed in the previous paragraph, is
described in the Ball Blue Book the same way. It is also listed as to be
avoided and potentially dangerous.
I've never heard of hot water bath canning referred to as open kettle when
the finished jars are processed in the hot water bath.
While it makes no difference to an individual who is processing the food
correctly, it can make a huge difference to others who understand
different definitions for the terms. If someone had told me that
something could be canned by the open kettle method, I would have done it
as I had been taught as a child (and the old canning books described) and
as it is currently defined. The life-saver would be checking a current
reliable source for specific directions, which, of course, should always
So, in your family, what was it called when the ingredients are cooked and
placed in the jars immediately with no further processing?
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