Oven-canning tomatoes is a practical and flavorful way to preserve the taste of ripe summer tomatoes. This method involves using your oven to sterilize and seal jars filled with tomatoes, which allows you to enjoy the vibrant flavors of fresh tomatoes long after the growing season has ended. The process begins by selecting ripe, firm tomatoes—Roma or other paste varieties are ideal due to their low moisture content and rich flavor. The tomatoes are first blanched to remove their skins, then packed into sterilized canning jars. To ensure proper acidity and safe preservation, a small amount of lemon juice or citric acid is added to each jar, along with optional herbs or spices for added flavor.
Once the jars are filled, they are placed on a large baking sheet and baked in a preheated oven to achieve the necessary heat treatment for sealing. This method not only effectively sterilizes the jars but also helps to intensify the tomato flavor by allowing the tomatoes to simmer gently in their own juices. After baking, the jars are left to cool and seal properly. This technique is particularly useful when you want to preserve a large batch of tomatoes at once and is a great way to maintain the taste of summer tomatoes throughout the year. Just be sure to follow safety guidelines for acidity and processing times to ensure that your canned tomatoes are both delicious and safe to eat.
Ingredients:
- 3-4 pounds of ripe tomatoes (Roma or paste tomatoes are preferred)
- 1 tablespoon lemon juice or 1/4 teaspoon citric acid per jar
- Salt (optional, to taste)
- Fresh herbs (like basil or oregano) or spices (like garlic powder) (optional)
Equipment:
- Oven-safe canning jars with lids and rings
- Large baking sheet
- Large pot for blanching tomatoes
- Canning tongs or jar lifter
- Clean kitchen towel
Instructions:
- Preheat the Oven: Preheat your oven to 200°F (93°C).
- Prepare the Jars: Wash your canning jars, lids, and rings in hot, soapy water. Place the clean jars on a baking sheet in the preheated oven to sterilize them, leaving them in the oven for about 10 minutes. Keep the lids and rings in hot water until ready to use.
- Blanch the Tomatoes: Bring a large pot of water to a boil. Prepare a large bowl of ice water. Cut a small “X” on the bottom of each tomato. Boil the tomatoes in batches for about 1-2 minutes until the skins start to peel away. Use a slotted spoon to transfer the tomatoes to the ice water to cool. Once cooled, peel off the skins and remove any stems.
- Prepare the Tomatoes: Cut the peeled tomatoes into halves or quarters, depending on their size. If desired, you can also remove the seeds.
- Pack the Jars: Place the tomatoes into the prepared sterilized jars, packing them tightly but leaving about 1/2 inch of headspace at the top. Add 1 tablespoon of lemon juice or 1/4 teaspoon of citric acid to each jar. If using, add a pinch of salt and/or a few fresh herbs or a sprinkle of spices.
- Seal the Jars: Wipe the rims of the jars with a clean towel to remove any residue. Place the hot lids on the jars and screw on the rings until they are fingertip-tight.
- Bake the Jars: Place the filled and sealed jars back on the baking sheet in the oven. Bake at 200°F (93°C) for 1.5 to 2 hours. The heat will help to seal the jars.
- Cool and Store: Carefully remove the jars from the oven using tongs or a jar lifter. Let them cool on a clean towel or cooling rack. As the jars cool, you should hear the distinctive “pop” of the lids sealing. Once completely cooled, check that the lids are sealed by pressing in the center of each lid—if it doesn’t pop back, the jar is sealed.
- Store: Store the sealed jars in a cool, dark place. Properly canned tomatoes should keep for up to a year.
Enjoy your preserved tomatoes in sauces, soups, and stews throughout the year!
