Introduction to Using a Pressure Canner: Canning Basics
Updated: Oct 25
Pressure canning sometimes gets a bad rap because people fear it. Not here at Wisdom Preserved, we love having homemade, pressure canned, shelf-stable goods in our pantries.
Today we are teaching you how to use a Pressure Canner.
Pressure Canning Food
Pressure canners uses heat and pressure over a specific amount of time to preserve and seal foods in jars. Foods like meat and vegetables are low acid foods and must be processed in a pressure canner. They must be heated to 240°F and held there for the time specified by the recipe to destroy all bacteria, spores, and toxins they produce. Because of the pressure, the temperature can exceed the boiling point of water. At 10 pounds of pressure, using a weighted-gauge canner, the temperature will reach 240°F (at or below 1,000 feet above sea level), which is hot enough to destroy the bacterial spores that emit toxins. If you are located at an elevation greater than 1,000 feet above sea level, you must increase the processing temperature by adjusting the pounds of pressure used; the processing time remains the same.
There are more components to the pressure canner than the water bath due to the need to maintain and monitor the pressure level. Each pressure canner is a little bit different so it is a good idea to familiarize yourself with the model that you have. If you do not have the owner’s manual often companies offer an online version for reference.
The basic parts of a pressure canner besides the pot and the lid are some kind of rack to keep the jars from resting directly on the heat of the bottom, a gasket or tightening knobs for sealing the lid to the pot and pressure monitoring equipment (either guage or weight). If you have a gasket, it should be checked regularly to be sure it will seal. If it does not seal, pressure will never be maintained. Most hardware stores offer new gaskets or they can be found online but be prepared with your model number because there are many different kinds available. There is an overpressure plug that should be changed at the same time that usually comes in the same package. If for some reason your pressure went up too high this would blow out and release the pressure quickly. (Probably breaking your jars in the process.)
On top of all pressure canners is a dial or weight. This is the pressure regulator. The pressure regulator controls the pressure inside the canner. The pressure gauge or weight is how you monitor the level of pressure in your device. It should be checked occasionally for accuracy. Agricultural university extension offices often offer that service. The pressure indicator is another safety feature that you can use to assess if there is pressure in the unit. The vent allows steam to escape which creates the vacuum that helps seal the jars. The pressure regulator is the little weight that goes over the vent. It maintains the pressure up to 15 pounds of pressure and then it will begin to rock releasing some of the pressure.
There are three types of pressure canner regulators:
One-Piece Pressure Regulator: Use this type of pressure canner by adding or removing weights to set the pounds of pressure. Set the regulator on top of the vent pipe to start the pressurizing process. Use your stovetop heat to regulate the gain and loss of heat/pressure inside the pressure canner. This type of regulator rocks and rattles when it nears the weight limit.
Dial-Guage Regulator: A dial regulator shows the exact amount of pressure inside the pressure canner. Use your stovetop heat to regulate the gain and loss of heat/pressure inside the pressure canner. A Dial-Guage Regulator should be inspected for accuracy annually.
Weighted-Guage Regulator: The weighted regulator is made of a disklike piece of metal that should be placed on top of the vent pipe to process the correct pounds of pressure. Like a one-piece regulator it rocks and rattles when it nears the weight limit.
If for some reason you do not have the jar rack you could place jar rings on the bottom of the pot to keep the direct heat away from the jars.
Preparing Your Pressure Canner and Filling Jars:
Same as with the Boiling Water Bath Canner, we like to prepare our canning equipment while the recipe we are making is cooking. Don’t neglect what you are making, be sure to stir occasionally so it does not burn. If you don’t multi-task well then you should prepare your canning equipment ahead of time.
The first step is to heat your jars using a moist heat.
We use two different methods to heat up our jars because all that is needed is a moist heat.
Place them in the dishwasher on high heat.
Place them in boiling water.
Gather your tongs, ladle, jar lifter, lid lifter, chopsticks, clean cloth, and any other needed supplies for canning.
Place 3 quarts worth of warm water in the bottom of the pressure canner. (Refer to your owner’s manual to verify for your specific canner).
Place a small saucepan on the stove on simmer and insert your lids to soften the seals.
Prepare your recipe of choice.
Fill your jars leaving the appropriate amount of headspace to match your recipe.
Use a chopstick to remove any air bubbles.
If you spilled on the edge or rim of the jar, use a clean cloth to wipe the rim clean.
Place the lid on top of the jar and add the ring. Tighten the ring to fingertip tight.
Place the jars into the pressure canner.
Check to be sure you can see light through the vent hole in the lid. (This will occasionally get blocked by food particles.)
Lock your lid in place. (There are usually marks on the lid to help guide you.)
Bring water to a boil slowly to avoid losing fluid from your jars. (Medium-high heat.) Once it begins to steam out of the vent start a timer for 10 minutes.
After 10 minutes of the vent steaming, place your weight or pressure regulator on top of the vent and begin monitoring your pressure.
Once you have reached the proper pressure for your recipe and elevation, set your timer for the recommended time and begin adjusting the heat to maintain pressure. If, at any point in the canning process, the pressure goes down below your target you need to bring it back up to the correct pressure and restart the timer. As you become more practiced at this it gets easier. (Don’t forget to adjust the pressure for elevation change if you are above 1000 feet in elevation.)
After the allotted time, remove the pressure canner from the heat and allow the pressure to drop naturally. Do not remove the weight or regulator until the canner has completely depressurized. You know the pressure has dropped completely when both the gauge and the pressure indicator show no pressure.
Once your canner pressure has dropped to zero, you may now remove the weight and the lid. Be careful of the escaping steam as it is very hot. Allow the jars to sit for 10 minutes before removing them from the canner.
Use your jar lifters to remove the jars from the canner and place them on a towel on a level surface.
Space the jars about an inch apart on the counter for 24 hours to cool and completely seal. Leaving space between each jar so they will cool down quickly is important because if the jars cool too slowly it can alter the taste of the food due to bacterial growth.
Allow the jars to sit for 24 hours and then check for a good seal. You know it has a good seal if the middle button has been dimpled down. If it does not seal put it in the refrigerator for current use.
Store your canned foods in a cool, dark, and dry location. They are best within the first year but are still good for up to 3 years. After that, they begin to lose their nutritional value.