Boiling Water Bath Canning Method
High acid foods are processed in a boiling water bath canner,
the canner can be any pot or kettle that is large enough for the
canning jars to be completely immersed and surrounded in boiling water.
A boiling water bath canner should have a tight fitting lid and a metal
basket to hold the canning jars off the bottom and away from each other.
Jars should be held off the bottom so the heat can penetrate properly
and the jars should be divided so they don't bump into each other
or tip over.
The jars should be covered by one to two inches of water when it is boiling,
so the heat penetrates the food at the top of the jars. Also, there should be
one or two inches of air space between the top of the boiling water and the
top of the canner.
The boiling water bath canning method is recommended for canning fruits,
tomatoes, foods with vinegar added, like pickles and relishes.
Foods high in acidity are the easiest foods to can. Because bacteria
do not thrive in acids, the temperature of the boiling water bath canning method
is good for processing acid foods.
Butters,jellies, conserves, jams and preserves can also be processed
at boiling temperatures.
Steam Pressure Canning Method
Low acid foods must be processed in a steam pressure canner, it is a heavy
kettle with a lid that is clamped or locked down to make a tight seal. The lid
is fitted with a safety valve, a vent and a pressure gauge.
There are two types of steam pressure canners, one has a dial gauge and
the other has a weighted gauge.
The dial gauge type has to be checked often for accuracy, because if it is not
correct, the processing of your canned goods will not be right and the bacteria
and botulinum spores will not be killed.
The vent on the pressure canner allows steam to escape under controlled
pressure. When the steam is pressurized inside the canner, its temperature
will exceed the boiling point of water. At 10 pounds pressure the temperature
will reach 240 degrees, which is enough to kill bacterial spores.
If the vent should become clogged, the safety value is designed to pop,
releasing pressure and preventing the canner from exploding.
Because of the danger of food being under processed and working with steam under
pressure, it is very important that all parts of the pressure canner are kept clean
and in good working order. If this is done, and the foods are processed for the
right amount of time and temperature, pressure canning is a reliable method
for canning low acid foods.
If, for any reason the pressure drops during the processing time, the whole
process should be repeated.
Always follow the manufacturer's direction.
Everything needed for canning and any additional equipment needed can be
bought on line. The best place on line is Ball Canning Supplies
Tip; Buy a Blue Book from Ball, The guide to home canning and freezing.