Boiling Water Bath Canning
This method of water bath canning is easy and popular. It should be used only for high-acid foods. These include fruits, tomatoes, and some foods with vinegar added. It can be used with both raw or cold pack and hot pack method of filling the jars. In the chapters on canning specific produce, we will recommend which method to use.
You’ll need a boiling water bath canner. This is a big kettle or stock pot with a tight-fitting cover. The canner also has either a metal basket or rack. This basket or rack holds the jars off the bottom of the kettle so that hot water can circulate underneath. The rack also keeps the jars separate from each other, and has handles so that all the jars in the kettle can be lifted in or out at the same time.
The kettle must be deep enough so that the jar tops are covered by one inch of boiling water, with at least an additional inch or two of space above the water. Most quart jars are 7 to 71⁄2 inches tall, so a canner should be 12 or more inches deep.
This same kettle can be used in making jams, preserves, and marmalade.
STEP BY STEP INSTRUCTIONS FOR BOILING WATER BATH CANNING:
- Before beginning any canning recipe, prepare jars and lids as directed by manufacturer. Keep jars hot until ready to fill.
- Fill the canner half full of water, place it on the stove, and begin simmering. Heat another small kettle of water.
- Place raw or hot-packed food in the clean, hot jars, leaving the recommended head space.
- Add salt if desired. Salt is not necessary for preservation. If you use salt, use Mrs. Wages® Pickling and Canning Salt which does not contain additives that will make the liquid cloudy.
- Run a plastic bubble freer (much better than a table knife or spatula, although a narrow spatula may used) around the inside of the jars to release any air bubbles.
- Wipe the top of each jar with a damp cloth or paper towel if your syrup contains sugar, or with a dry towel if not. Do this thoroughly and carefully to prevent small particles of food from interfering with the seal.
- Center the lid over the mouth of each jar. Screw the band down firmly to finger-tight. Do not over-tighten the bands as this may damage the rings and/or not allow air to escape during processing.
- Lower the jars into the boiling water canner with a jar lifter. Make sure jars are not touching to get good heat circulation. A wire basket or rack will keep the jars properly spaced.
- Add boiling water from the other kettle to cover the jars by one or two inches.
- Put canner lid on, turn heat up, and start timing when water is at full boil.
- When the recommended time is up, remove the canner from the heat and remove the lid. Leave jars in the canner undisturbed for five minutes. This added time completes the processing and helps create a better seal. Remove the jars with a lifter or by lifting out the basket. Lift jars straight out of the canner without tilting. Do not leave the jars in the canner overnight — this can result in an unsafe product.
- Put the jars on a cake rack or towel in a draft-free area. Don’t knock them together; they will shatter easily when hot. Leave about an inch of space between jars so they can cool adequately. Do not cover them and keep them out of drafts. Do not turn the jars upside down.
- Do not tighten or loosen the screw bands. Leave jars undisturbed for 12 to 24 hours to cool.
- Test the seal by pressing on the lid or tapping it with a spoon. A sealed lid will not give and will have a hollow sound when tapped. If the seal is not good, you can reprocess the jars within twenty-four hours of the original processing. Be sure to use new lids. However, to eliminate over-cooking which results in loss of nutrients and quality, we recommend immediate refrigeration and early use, or freezing the product instead of reprocessing. Try to discover why your jars didn’t seal. The most common reasons are a bit of food caught between the lid and the jar rim, and cracks or nicks on the jar rim.
- Remove the screw bands from the jars.
- Wipe the jars clean and label them with the produce name, its origin, and the date. This is helpful when you’re planning next year.
- Store the jars in a cool, dry, dark place. Dampness rusts the lids and causes the seals to deteriorate. Light tends to destroy vitamins and fade colors. Freezing and thawing will ruin the food’s taste and possibly break the seal.
Plan to eat canned foods within one year. While the food may be safe to eat for much longer, there’s no reason to settle for old canned goods when next year’s harvest will supply good fresh produce.
Boil all home canned vegetables in a covered saucepan at a full rolling boil for 10 minutes before serving. Home canned spinach or corn should be boiled for 20 minutes. If the food looks spoiled, foams or has an off odor during heating, destroy it. Do not taste it!
Altitude Adjustments For Water Bath Canning
Because water boils at lower temperatures as altitudes rise, it’s necessary to allow more time during processing. The USDA recommends increasing processing time by 1 minute for every 1000 feet of altitude for those items processed 20 minutes or less. For those products processed for more than 20 minutes, it is recommended to increase the processing time by 2 minutes for every 1000 feet of altitude.
NOTE: The processing times provided in this book are based on canning at or below 1,000 feet below sea level.
Source: Mrs. Wages Home Canning Guide and Recipes, Copyright 2012. All Rights Reserved. For even more canning tips and over 120 tested recipes from our test kitchens, be sure to order the Mrs. Wages Canning Guide.