Preparing Jars for Canning and Boiling Water Processing

Filled canning jar held above boiling water
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When you're canning or preserving fresh fruits and vegetables from summer's bounty, it's important to know how to prepare and fill the jars, how to handle lids, and how to process filled jars in a boiling water bath canner.

Jar Preparation

  1. Wash the jars, lids, and bands in hot, soapy water. Rinse and drain. Fill the canner with water and place the jars on the rack. Cover and bring to a simmer over medium heat. Reduce heat and keep the jars hot until you're ready to fill them.
  2. Put the flat lids in a saucepan and cover with water; bring just to a simmer over medium heat. Do not boil. Reduce heat and keep them hot until you're ready to use them.
  3. Put the screw bands near your work area. There's no need to heat the bands.

Filling Jars

  1. Prepare your recipe. Have a trivet or rack ready in your work area for the hot pot.
  2. Working with one jar at a time, use canning jar tongs to remove jars from the hot water to your work area. Fill the jars using a ladle, leaving the appropriate amount of headspace that your recipe requires. A canning funnel comes in handy for this step.
  3. Slide a small nonmetallic spatula or plastic knife around in the hot mixture to remove any air bubbles. Using a damp clean cloth or paper towel, clean the jar rims and threads.
  4. Center the lids on the jars, so the sealing compound is in contact with the rims. Screw the bands down just to fingertip tightness. Do not overly tighten. A magnetic lid lifter makes it easier to remove lids, one at a time, from the hot water.

Processing Filled Jars

  1. Return the filled jars to the rack in the hot water in the canner. Lower the rack and adjust the water level, so there is at least 1 inch of water above the tops of the jars.
  2. Cover the canner and bring to a full boil. Once the water is at a full boil, begin timing the processing time required by your recipe.
  3. Turn off the heat, remove the cover, and let the jars stand in the water for 5 minutes. Using the canning jar tongs, remove the jars to a rack or heavy towel to cool. Do not tilt, turn, or dry, and do not disturb the lids or tighten the bands.
  4. After 24 hours, check for seals and remove the bands.
  5. Refrigerate any unsealed jars and use within a few days or reprocess, heating the liquid again (according to recipe instructions) and canning in sterilized jars with new lids.
  6. Label properly sealed jars, wipe the jars and threads clean, and store in a cool, dark place.