Tomatoes top the list of popular garden produce and commonly canned foods. But, some people still have not heard that when canning tomatoes of any variety, adding an acid is a vital, non-optional safety step, even though this safety protocol has been recommended for nearly 30 years.
Properly acidified tomatoes can be safely processed in a boiling water bath or pressure canner. Add the acid to the jar before filling with tomatoes. Use 1/4 teaspoon commercial citric acid powder, or 1 tablespoon bottled lemon juice or 2 tablespoons vinegar per pint. Citric acid gives the best results with no added flavor of its own. Lemon juice and vinegar create competing flavors which some find objectionable, but all three options produce safe canned tomatoes.

Exhausting a
Pressure Canner
Yes, canning can be exhausting, but that’s not what is meant by exhausting (or venting) a pressure canner.
Dry air trapped in a pressure canner lowers the internal temperature and may result in under-processing.
To be safe, USDA recommends all pressure canners must be exhausted 10 minutes before they are pressurized.
Load the canner with filled jars and lock the canner lid in place. Leave the weight off the vent pipe or open the petcock on older models. Heat the canner on high until steam flows from the vent. When a visible funnel of steam flows continuously, set a timer for 10 minutes. After 10 minutes of continuous steam, close the petcock or place the weight on the vent pipe to begin pressurizing the canner.
Learn more at www.bookstore.ksre.ksu.edu/pubs/MF3242.pdf.

Linda K. Beech is a family and consumer sciences agent with the Cottonwood District K-State Research and Extension. Contact her at 785-628-9430 or email lbeech@ksu.edu.