Basic Skills: Water Bath Canning

Background Information

Boiling water bath canning is recommended for processing high-acid foods. The temperature of the boiling water bath canner is 212 degrees F (100 degrees C) and will kill bacteria in high-acid foods. The boiling water bath canning method is used for processing fruits, pickles, relishes, acidified tomatoes, fruit jellies, jams, butters, marmalades, and preserves. Always check up-to-date canning information for correct processing times. For higher altitudes, processing times will need to be extended one minute for each 1000 feet above sea level. The time needed to process high-acid foods in boiling water ranges from 5 to 85 minutes depending on the food, style of pack, and jar size.

Equipment Preparation

Steps to Follow
  • Assemble all equipment and utensils.
  • Place boiling water bath canner, filled half full with water, on the stove burner and begin to heat. Make sure canner has a removable rack that will fit inside the canner. The canner should be large enough to allow the water to boil 1 to 2 inches over the jars when they are placed on the rack in the canner.
  • Place an extra kettle of water on the stove burner in case extra boiling water is needed to cover the jars in the canner.
  • Check all canning jars for nicks or cracks. Discard if damaged.
  • Wash jars and bands in hot soapy water; rinse in hot water. Jars for pickles and fruit juices (which have less than 10 minutes of processing time) should be boiled in hot water for at least 10 minutes. Each 1000 feet above sea level will require 1 additional minute.
  • Use new canning lids for each jar. Prepare lids according to manufacturer's directions.

NOTE: Use only standard canning jars for boiling water bath canning. Peanut butter or mayonnaise jars are not acceptable for canning.


  • Make sure water in canner is boiling.*If using the raw pack method, have the water in the canner hot, not boiling. Placing raw pack jars in boiling water may cause the jars to break.
  • Place jars in canning rack, then place rack in canner while water is boiling. ** Place jars far enough apart to allow for circulation of water around jars. Water should be 1 to 2 inches over the tops of the jars when boiling.
  • Begin timing for processing as soon as the water returns to a rolling boil. Use the table as a processing guide; however, at higher altitudes (over 1,000 feet) you will need to adjust processing times.

The canner should be covered during processing. The hot boiling water should cover the tops of the jars during the entire processing time. (See individual recipes for exact processing time.)

After processing time is completed, remove hot jars and place on a towel or rack to cool. Keep jars out of drafts. DO NOT TURN JARS UPSIDE DOWN. When jars have cooled, check for sealing.

Testing the Seal

3-Way Test For Checking The Seals On The Jars:
  • Hear the seal - Hear the "plink" as lid snaps down while jar is cooling, or tap lid with spoon when jar is cold. A clear ringing sound means a seal.
  • Observe the seal - If the lid is curved down, the jar is sealed.
  • Press the seal - After the jars have cooled, press the center of the lid. If it is down and will not move, the jar is sealed.
  • Remove ring bands from jar and store in a cool, dark, dry place. Ring bands free of rust may be reused. Never reuse lids for canning purposes.

NOTE: If a jar is not sealed within 24 hours, reprocess contents with a new lid or refrigerate and use in the next 1 to 2 days.

CAUTION: Never taste or eat food from a jar with an unsealed lid, swollen lid, or if the food shows signs of spoilage.