How to Can Food With the Water Bath Method

Canning is a method of preserving food that uses Mason jars to extend the shelf life of certain ingredients and meal accompaniments. The jars are heated using hot water to kill off hazardous microorganisms that can lead to illnesses such as botulism. The canning process also involves creating a vacuum seal to remove any air from the canning jars, eliminating enzymes that cause food spoilage. Common home canning recipes include tomato sauces, jams, jellies, salsas, and soups. There are two primary canning methods—boiling water bath canning and pressure canning—but pressure canning is only recommended for experienced home cooks.

Water bath canning is great for canning high-acid foods with a natural pH of 4.6 or lower. If you wish to use this method with slightly less acidic foods, add lemon juice or citric acid to the food.

1. 1. Gather your supplies. Canning supplies include wide-mouth canning jars, two-piece metal jar lids (flat metal discs and rings), measuring cups, a canning funnel, a jar lifter, a large stockpot, and a wire rack that can fit in your stockpot.
2. 2. Sterilize your jars. Before filling your canning jars, thoroughly wash them with hot, soapy water and boil them for at least ten minutes. When boiling your jars, it's imperative not to let the glass jars touch the bottom of the pot as the high heat could break them. Place a wire rack at the bottom of the pot to keep them elevated. Let the jars air-dry before filling them.
3. 3. Prepare your food for canning. Follow the recipe for the jam, jelly, or whole fruits or vegetables you wish to preserve.
4. 4. Fill your canning jars. Use a canning funnel to fill your canning jars, leaving the amount of headspace between the food and the top of the jar specified by your recipe. Be careful to avoid getting residue on the rim of the jar as this can prevent the lid from sealing properly. Gently tap the filled jars on the counter to remove air bubbles before sealing them with your two-piece lids.
5. 5. Bring a large pot of water to a boil. The pot should be large enough so that at least one inch of water will cover the tops of your jars.
6. 6. Put the jars in the water. Completely submerging glass jars in boiling water will heat the contents to a temperature that makes them safe to store and eat at a later date. Wipe off the rims of the jars and tighten the jar lids. Use tongs, a soup ladle, or jar lifter to lower the filled jars into the water. Leave the jars submerged for the amount of time specified by your canning recipe.
7. 7. Remove the jars. Remove the hot jars with your jar lifter and place them on a wire rack to cool.
8. 8. Check the seals. Gently press down in the center of each jar lid. If the lid presses down and snaps back, it is not vacuum sealed. Remove the ring and lid and clean the rim of the jar. Place a new lid on the jar and redo the process until you get a vacuum seal.
9. 9. Store your jars. Remove the lid rings before storage. Leaving the rings on the jars could cause rust or mold to form on the jar. Store jars in a cool, dark place for up to twelve months.

Pressure canning is an effective method for canning low-acid foods, such as meat, seafood, and soups. Low-acid vegetables, such as green beans, beets, and potatoes, can be canned this way as well. Pressure canning low-acid foods effectively eliminates the potential for the growth of botulism spores. Botulism spores die when canned under ten to fifteen pounds of pressure per square inch at sea level. While effective, pressure canning can be a dangerous process and is only recommended for experienced home cooks.

Foods can be packed into jars raw or hot, meaning you can preserve uncooked or cooked food. There are some differences between these processes.

• Raw packing: When raw packing food, place raw, room-temperature foods in a jar. Pour boiling water into the jars to cover the raw foods, leaving the amount of headspace in the jar specified by your recipe. Since air within the foods is not removed during a cooking process, raw-packed foods will likely become discolored within two to three months. Raw-packing is an acceptable method for packing veggies to be processed in a pressure canner.
• Hot packing: Hot packing is preferred for its tendency to yield better color and flavor. When hot packing, cook the foods for the specified amount of time and add to the jars along with the hot cooking liquid.

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