Can your pressure canner pass the test?
- col-kate-shumaker
- June 5, 2025
- 116
It’s just about time to fetch canners out of the basement or garage. Fresh summer produce is on its way. Strawberries are ripening, gardens are being planted, and hopefully, that means fresh summer produce can’t be far behind.
I’m always happy to answer your questions, even though I rarely seem to give the answer you really want to hear. It’s good to know some of you are taking the time to ask questions and not just going ahead with something that may be unsafe.
Home canning is a relatively simple process, but there are so many variables that can affect your finished product and so many resources and recipes in circulation with unsafe processes. It is a good idea to make sure you are following the most recent safe home canning guidelines.
Most people have a healthy regard for the possible dangers of pressure canners. Usually, this respect is based on an old story of a pressure canner “blowing up” in someone’s grandmother’s kitchen. Regardless, it is important to realize pressure canners are safe if the safety precautions are followed and the canner is used properly. Danger can arise when the unit isn’t maintained or is used improperly.
One of the recommendations for home canning foods safely is you use a pressure canner to process low-acid foods such as vegetables, soups, meat, poultry and fish. These low-acid foods must be pressure canned at the recommended time and temperature to destroy Clostridium botulinum, the bacterium that causes botulism food poisoning. Home canning low-acid foods in boiling water canners is absolutely unsafe because 212 F, the highest temperature reached in boiling water, is not high enough to destroy botulinum bacteria.
Pressure cookers and canners can be evaluated at several locations this summer at no charge. This service will be available on the following dates:
—Saturday, June 21 at Lehman’s from 9 a.m. to 1 p.m.
—Wednesday, June 25 at Mt. Hope Hardware from 9 a.m. to 1 p.m.
—Thursday, June 26 at Lehman’s from 9 a.m. to 1 p.m.
—Monday, July 21 at Keim Home Center from 12:30-4:30 p.m.
—Wednesday, Aug. 13 at Mt. Hope Hardware from 9 a.m. to 1 p.m.
—Thursday, Aug. 14 at Lehman’s from 9 a.m. to 1 p.m.
—Monday, Sept. 8 at Keim Home Center from 12:30-4:30 p.m.
If you would like to look for canner testing options outside of Holmes County, go to go.osu.edu/fcsfoodpreservation for a listing of other counties offering this service. If you can’t make these dates, we can schedule a time to test your pressure canner in our office for a small fee.
Individuals should bring their cooker or canner lids with dial gauges attached to the testing location during these times. If possible, we ask the person who will do the canning be present during the testing. It only takes a few minutes for the peace of mind of knowing your gauge is accurate. In addition to testing dial gauges, both weighted and dial gauge units will be evaluated on several other safety factors. Fact sheets on food preservation also will be available.
Here are some guidelines from National Presto Industries on important safeguards and maintenance of your pressure canner. These guidelines apply to most brands and styles of pressure canners/cookers.
Before use
—Check the vent pipe. Hold the lid up to light and look through the vent pipe to be sure it is not clogged.
—Check the air vent/cover lock to be certain it moves freely.
—Check the handles of the lid and body. If loose, tighten with a screwdriver before using.
—Do not use a pressure canner on an outdoor LP gas burner over 12,000 BTUs.
—Do not open the canner until internal pressure has been reduced to zero, the cover lock has dropped and no steam escapes when the pressure regulator is removed.
—When removing the canner lid, lift the lid toward your body so the steam escapes away from you.
—When normal operating pressure is reached, gradually lower the heat to maintain pressure.
—Supervise the canner closely when in use.
—Each time the canner is washed, remove the sealing ring/gasket, wash it in hot soapy water, rinse and allow to air dry. Do not store the sealing ring in the sealing ring groove in the lid. When not using the canner, store the ring loosely at the bottom of the canner.
—Replace the overpressure plug and sealing ring if they become hard, deformed, cracked, pitted or worn. This should be about every three years. Always replace both pieces at the same time. Exposure to cooking oil may cause these parts to deteriorate more rapidly.
—If your canner has a dial gauge, remember this is a very sensitive instrument. Do not submerge the gauge in water or let the gauge come in contact with any liquid. If this happens, the inside mechanisms of the gauge may be damaged.
Remember home food preservation can be safe, simple and easy to learn.
Kate Shumaker is an OSU Extension family and consumer sciences educator and may be reached at 330-674-3015 or Shumaker.68@osu.edu.