Agriculture Reference
In-Depth Information
canning method for a vegetable (
Table 19
,
page 198
), it is
because I have determined that it is better preserved using
some other method.
An age-old method for canning foods that cannot be safely
canned otherwise is to raise the acidity of the food by either
fermenting it or adding vinegar. Sauerkraut is a great example
because cabbage is not suitable for either canning or freezing
in its fresh state, but if acidified through lactic acid
fermentation (and thereby becoming sauerkraut), it can be
canned in a boiling water bath while retaining its most
important health benefits. (Technically, with great care, you
can freeze grated cabbage, but your results may vary.) Pickles
are made either by fermenting vegetables in a brine (which
raises their acidity through the production of lactic acid) and/
or by adding vinegar. These methods create a sufficiently
acidic product so that only a brief period in a water bath
canner is required.
Boiling water bath canning is suitable for all fruits, jams,
jellies, preserves, and pickles. Tomatoes are right at the
margin of pH 4.6, so they can be safely canned in a boiling
water bath if a known amount of citric acid (or commercial
bottled lemon juice) is added. The correct amount is one
tablespoon of lemon juice or 1/4 teaspoon of citric acid per
pint. Vinegar can be used instead, at the rate of two
tablespoons per pint, but it can cause off-flavors. The only
time I would recommend vinegar is in salsa. The acidity (or,
rather, the taste of the acidity) can be offset by adding two
tablespoons of sugar for every tablespoon of lemon juice,
which won't interfere with the canning process. While few
people choose to can figs (usually they are dehydrated
instead), it is worth noting that they are right on the border
