Canning Process
Canning
is a process that is used to preserve many different kinds of
food. We do it by putting food in Mason Jars and processing them
in a Steam Kettle under 5-20lb. of pressure. This simultaneously
cooks and disinfects the food.
The air we breathe and all foods in their natural state contain
microorganisms, such as molds, yeasts and bacteria as well as
enzymes. Food spoils when enzyme, mold, yeast and bacterial
growth is not controlled. Proper, safe home canning procedures control
the growth of spoilage microorganisms allowing us to keep food beyond
its normal storage period.
Home canning is not complicated. It is a simple procedure that applies
heat to food in a closed glass jar to interrupt the natural decaying
that would otherwise take place.
Safe home canning requires "heat processing" of all foods according to up-to-date, tested home canning guidelines.
This includes:
- placing prepared food in mason jars that can be sealed airtight with two-piece metal SNAP lids
- using the correct type of canner to heat the filled jars to a designated temperature for the food being processed
- maintaining this temperature for the
time specified in up-to-date, tested recipes to destroy spoilage
microorganisms, inactivate enzymes and properly vent air from jars
- cooling jars properly to allow lids to form a strong vacuum seal
When followed exactly, the "heat
processing" methods and times of up-to-date, tested home canning
recipes adequately destroy normal levels of heat-resistant
microorganisms. After processing and upon cooling, a vacuum is
formed and the lids seal onto the jars. This ensures home canned foods
will be free of spoilage when the jars are stored properly and remain
vacuum-sealed. The seal prevents other microorganisms from entering and
contaminating the food.
NOTE: The cooking time that is part of recipe preparation before the
food is placed in jars is not processing time. It does not alter
the"heat processing" time required for safe home canned foods. To
thoroughly destroy all microorganisms that may be in a specific food,
or that may contact the food as it is ladled into the jars, always heat
process the filled jars by the method and for the time specified in a
tested recipe from a reputable source.
How "heat processing" works: As the filled jar is heated, its contents
expand and internal pressure changes take place. These changes allow
gases or air to be "vented" from the jar. After processing,
the atmospheric pressure outside the jar is greater than inside due to
"venting". This pressure difference causes the lid to be pulled down
onto the jar causing a vacuum seal to be formed. The resulting seal
prevents microorganisms and air from entering and contaminating the
food.
