Now that you’ve spent all your money buying the pressure canning equipment, it’s time to practice! I could just say “Read the manual,” but then I wouldn’t be able to write this article. The instructions here are for my [amazon-product type=”text” text=”Presto 23 Qt Pressure Canner”]B0000BYCFU[/amazon-product]. But instructions do vary from model to model. For example, I also have an [amazon-product type=”text” text=”8 Qt Presto Cooker”]B0000Z6JIW[/amazon-product]. It’s instructions clearly state “Do not put oil on the gasket.” The 23 Qt instructions say that you can.
Get started by adding a few inches of water to the bottom of the canner. My canner has marks on the inside indicating ideal fill levels. The lowest mark is for canning. The middle mark is “half-full” or 11.5 qts, and the upper mark is 3/4 full or 17.25 qts. I usually fill just above the lowest line.
Then add some (about 1tbs) white vinegar to the water. This prevents nasty looking deposits in the canner and on the jars, but isn’t strictly necessary. Center the pot on a burner and set to high.
Remove the gasket from the lid and lightly oil with vegetable or canola oil and replace. Then lock the lid in place on the pot, and wait.
Pretty soon the water will start to boil. When the boiling gets intense enough, the pot will lock itself. When it does, start a 10 minute timer. This is the purge cycle. Since air does not follow the same gas rules as steam, air inside the canner can lower the desired temperature because temperature is maintained by hitting a target pressure, not by measuring temperature.
After the 10 minutes is up, add the weighted gauge to the steam vent to trap the steam. The pressure and temperature inside the canner will begin to rise. When the pressure reaches the setpoint of the weighted gauge, the gauge will start to noisily rock back and forth. The dial pressure gauge will also show the target temperature. Even though the weighted pressure gauge will regulate the pressure, you should still turn the burner down to maintain the pressure. Doing so during canning will ensure that you have enough water in the bottom to finish processing, but make sure the pressure never falls below the target pressure. If it does, you should start the processing time over.
Once you’ve held pressure for “long enough”, turn the burner off, and wait for the canner to depressurize. It will unlock when fully depressurized. Don’t remove the weighted gauge until after the canner has unlocked. As you remove the lid, remember that steam can be hotter than boiling water, and it will tend to go up and towards your face. So, be careful.
All that’s left to do is bask in the wonder of a sterilized pressure canner. Congratulations on your first practice run.