anning your own tomatoes is a rewarding way to preserve the bounty of your garden and enjoy the taste of fresh tomatoes year-round. Using a water bath canner is an accessible method for preserving high-acid foods like tomatoes. Here’s a step-by-step guide, based on the time-tested advice from the Ball Blue Book Guide to Preserving, to help you can tomatoes safely and effectively.
Step 1: Prepare Your Canning Jars
Before you begin, inspect your canning jars for any nicks, cracks, uneven rims, or sharp edges that might prevent sealing or cause breakage. Check the lids to ensure the sealing compound is even and complete, and make sure the bands fit properly. Wash the jars and two-piece caps in hot, soapy water, rinse well, and then dry the bands. Keep the jars and lids warm in a saucepot of simmering water (180°F or 82°C); do not boil the lids.
Step 2: Clean Your Jars
Clean jars and two-piece caps thoroughly using hot, soapy water. Rinse them well and dry the bands; set these aside for later use. Place the jars and lids into a saucepot filled with water that’s heated to a simmer (180°F or 82°C); ensure that the lids do not reach a boiling point. Keep the jars and lids submerged in the hot water until they are needed, removing them one at a time when required.
Fill your boiling-water canner to half its capacity with hot water. Position the rack higher up in the canner. Place the lid on the canner. Warm the water to a gentle simmer (180°F or 82°C) and maintain this temperature until it’s time for processing.
Step 3: Prepare the Tomatoes
Choose fresh, firm tomatoes free of cracks, spots, and growths. Wash and drain them. Prepare only enough tomatoes to fill one canner load at a time for best results.
Step 4: Blanch the Tomatoes
Place the tomatoes in a wire basket and lower them into a large saucepot of boiling water. Blanch them for 30 to 60 seconds or until the skins start to crack. Immediately transfer the tomatoes to cold water to stop the cooking process.
Step 5: Peel and Prep
Once cool, slip off the skins of the tomatoes, trim away any green areas, and remove the cores. You can leave the tomatoes whole or cut them into halves or quarters, depending on your preference.
Step 6: Pack the Jars
If packing the tomatoes in water, place them in a large saucepot, add just enough water to cover, and boil gently for 5 minutes. Using a jar lifter, remove a jar from the hot water, place it on a towel, and add 1 tablespoon of bottled lemon juice per pint jar or 2 tablespoons per quart jar. Pack the tomatoes into the jar, leaving a 1/2-inch headspace. Ladle the boiling water or cooking liquid over the tomatoes, maintaining the 1/2-inch headspace. Add salt if desired (1/2 teaspoon per pint jar or 1 teaspoon per quart jar).
Step 7: Remove Air Bubbles
Use a nonmetallic spatula to gently press back on the tomatoes and release any trapped air bubbles. Repeat this 2 to 3 times around the inside of the jar.
Step 8: Seal the Jars
Wipe the rim and threads of the jar with a clean, damp cloth. Use a lid wand to remove a lid from the hot water, place it on the jar, centering the sealing compound on the rim. Screw the band down evenly and firmly until resistance is met—fingertip tight.
Step 9: Process the Jars
Place each filled jar onto the elevated rack in the simmering water canner. Once all jars are filled and placed on the rack, lower the rack into the canner. The water should cover the jars by 1 to 2 inches; add boiling water if necessary. Cover the canner, bring the water to a rolling boil, and begin timing. Process pint jars for 40 minutes and quart jars for 45 minutes (adjust time for altitudes above 1,000 feet).
Step 10: Cool Down
Turn off the heat and remove the canner lid after the processing time is complete. Let the canner cool for a few minutes before removing the jars. Set the jars on a dry towel, spacing them 1 to 2 inches apart, to cool. Do not retighten the bands. Allow the jars to cool for 12 to 24 hours.
Step 11: Check Seals and Store
After the jars have cooled, check the lids for a seal by pressing on the center. If the lid is concave and does not flex up or down, the jar has a good vacuum seal. Remove the band and gently try to lift the lid with your fingertips. If it doesn’t come off, the jar is sealed properly. Wipe the lids and jar surfaces to remove any residue, label the jars, and store them in a cool, dry, dark place.
Canning tomatoes is a great way to ensure you have delicious, homegrown tomatoes available for cooking and enjoying all year long. With these steps, you’ll be able to stock your pantry with the flavors of summer to last through the seasons. Happy canning!
