Best practices when choosing home canning jars

The most important step in safe home canning is to follow an up-to-date research tested recipe, including using a standard glass jar. Jars for home canning come in a wide variety of sizes, ½ pint, pint, 1½ pint, quart, and ½ gallon sizes. Not all sizes can be safely used in a recipe, so check prior to canning. Regular and wide-mouth, threaded Mason-type jars are the best choice. With careful use and handling, jar seals and vacuum are excellent and jar breakage is rare.

With traditional Mason-style jars in short supply, some home canners are asking questions about commercial pint- and quart-size mayonnaise or salad dressing jars. Mayonnaise-style jars are generally made from thinner glass and may be less expensive. While these jar styles may be used for boiling water or atmospheric steam canning, you should expect more seal failures and jar breakage.  Mayonnaise-style jars should not be used for pressure canning due to the high rate of jar breakage.

Regardless of whether you choose the traditional Mason-style or mayonnaise-style jar, make sure that the jar that you choose accepts a metal lid. Best practices for home canning recommend metal 2-piece lids for quality and safety.

Best practices for canning with traditional jars. There are several tips that will help ensure that the items that you can at home are delicious and safe.

  • Carefully inspect jars for nicks and cracks. Over time, jars can become scratched and will break more easily.  Set these jars aside for other, non-canning uses.
  • Wash jars with warm soapy water and rinse well before each use. A dishwasher is handy for washing jars (and lids) and for keeping them warm and ready for canning.
  • Jars should be warmed prior to filling.
  • Be sure to monitor headspace and wipe jar rims before applying the lid to help ensure a good seal.

It generally isn’t necessary to sterilize jars prior to canning.  However, for products such as jams and jellies where the processing time is less than 10 minutes, filling into sterilized jars will help ensure a longer shelf life once opened. To sterilize empty jars, boil for 10 minutes prior to filling.

Sourcing jars for home-based canning. Many home supply stores and national retailers sell traditional home-canning jars. Familiar brands such as Ball and Kerr have been harder to find the last year. Some consumers have noticed inferior quality of canning supplies ordered from third party vendors this last year. To ensure quality, consider ordering directly from the manufacturer or their representative.

Stay well and food-safe. Barb

Published on April 21, 2021