2.2 – PRESSURE TREATMENT

for canning vegetables and low-acid foods

Foods with a pH above 4.6 require a treatment under pressure to be safely canned at home. Their low acidity can not assist in the preservation of the products. Only a prolonged exposure to high heat ensures the destruction of all harmful microorganisms.
This product category includes all the vegetables (not marinated) and all products of animal origin (meat, poultry, seafood).
Pressure canning, in a pot-type autoclave, is used to process foods at temperatures that can not be achieved by the boiling water-bath method. This high temperature is essential to ensure the destruction of some microorganisms that can survive at 212F (100C).
pressure canner

You will need:
(1) Recipes indicating the required time and pressure for canning.
Warning: If a recipe was published before 1989 it is likely that the recommended storage methods do not take into account the latest research.
(It is possible to establish your own method and processing time but it takes steps for research and testing that goes beyond the scope of this short guide).
If you’re taking your first steps in home canning, we strongly recommend that you start with one of the recipes that you will find at the end of this guide.

(2) A pressure canner (autoclave) for home canning.
This large pot has a fitting lid, a pressure indicator and a bottom grid.
More costly than a simple boiler but more durable and easier to maintain. This type of pot is easy to find on the market.
Avoid “pressure cookers” that are generally too small and do not have precise mechanism of pressure measurement.

(3)”MASON” glass jars with their “snap” lids and closure rings.
Do not reuse jars of commercial products that are generally designed to be disposable. They may explode when pressure-treated.

(4) A clamp for handling the jars.

(5) A wide-mouthed funnel for filling the jars.

(6) A magnetic wand to remove the lids from the hot water.

(7) A kitchen timer or some other reliable instrument to measure the processing time.

(The funnel, tongs and magnetic strip are often sold in “kit”).

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