Johnston: Testing your pressure canner gauge important

Spring is in the air and canning season is just around the corner.

I have my squash and tomato plants ready, and am just trying to find the time to get them in the ground (I’m sure many of you can relate).

Later this summer you will hopefully see all the ‘fruits’ of your labor as you pick plenty of vegetables from the garden.

One good way to preserve all those great fresh veggies is to pressure can them. If that is your plan, now is the time to make sure your pressure canner is in good condition and the dial gauge is working properly.

Doing this will ensure your food is canned safety and properly.

First, check the rubber gasket that fits around the lid.

It should be soft and flexible, not dry, cracked or brittle.

Also make sure any small vent pipes or other openings are clean and open all the way through. You should be able to see light through the vent pipe.

Second, get the dial gauge on your canner tested for accuracy before you use it.

Every pound of pressure on the gauge is important to ensure the temperature inside the canner is high enough (240 degrees Fahrenheit) to kill the spores that can cause botulism.

We do pressure canner gauge testing at the Clark County Extension Office, so call and schedule an appointment. You will need to bring the canner lid with the gauge to the office. The test will only take a few minutes.

It is important to make sure the gauge is accurate before canning food. If your gauge is reading high, the temperature inside your canner will be lower than expected. Food will be under-processed and botulism could result.

If your gauge is reading low, the temperature inside the canner will be higher than expected.  Foods will be over-processed. Over-processing is not a food safety issue, but can lead to poor-quality canned foods.

If testing shows your gauge is off by just one or two pounds, pressure adjustments can be made during processing to ensure safe, high-quality canned foods. We can guide you in making those adjustments.

If your gauge is off by more than two pounds, send it to the manufacturer for recalibrating or replace it if necessary.

The safety of your pressure canning process is only as good as the accuracy of your dial gauge.

Getting your gauge tested can help ensure not all your hard work in the garden is ruined by food safety concerns.

Shonda Johnston is the Clark County Extension agent for family and consumer sciences. She can be reached at 859-744-4682 or by email at