Canned Tomatoes
Home preservation is safe so long as the cook does not deviate from the recipe. You must add citric acid and salt to each jar. Do not add additional ingredients, as they may compromise the safety of the recipe. If for any reason the seals loosen or the food looks, smells, or seems off in any way, throw it out.
Yield: Roughly speaking, 5 pounds/2.5 kilos of tomatoes=5 pint jars of tomatoes. A pint jar holds 2 cups/470 ml tomatoes.
Note: This recipe follows the American system of water bath canning. Please read the post before starting. The recipe that follows is a summary of the detailed information given in the post. Please read the post before starting.
For 5 pounds/2.5 kilos San Marzano or Roma Tomatos:
5 teaspoons canning salt
1.5 teaspoons citric acid
Sterilize your jars by running them through the dishwasher or washing them in hot soapy water, rinsing them thoroughly, and placing them in a low oven.
If your lids and bands are new, you do not need to wash them. Place them in a small saucepan of water. Put the saucepan on a back burner over low heat.
If reusing bands, wash in soapy water, rinse well, and follow above directions.
Put the canner on the stove. Make sure the rack is in place. Fill with water. Place on low heat. Note that water level must be at least three inches/2.54 cm above jars.
Set your kitchen up as noted in post, above, to prep the tomatoes. Dip tomatoes in boiling water to loosen their skins.
Remove tomatoes to cutting board. Halve tomatoes, remove skins, and core. I do this by making a triangular cut to get the stem end out. Toss skins and cores into strainer set in a large bowl.
Once all tomatoes are skinned and cored, squeeze each half over strainer to seed it. Don’t worry about getting every single seed out. Move the seeded tomato halves to large pot.
Once all the tomatoes are seeded, move the large pot to the stove. Bring to a low boil, stirring occasionally, for five minutes.
The tomato juices collected in bowl beneath the strainer may also be canned. If you run short of liquid in the final jar, top it up with water.
Place funnel in jar. Add a 1/4 teaspoon citric acid and 1 teaspoon salt. Ladle the tomatoes in, leaving 1/2 inch (1.27 cm) headspace in each jar. You’ll notice a glass line at the top of the jar–don’t fill beyond that, or you’ll compromise the seal.
Push down any bits of tomato sticking up past the fill line with a small clean spoon. Do the same if you see any air bubbles.
Clean jar rims with a paper towel or rag dipped in white vinegar. Cap each jar fingertip tight and lower into canner.
Once all the jars are filled, bring the canner to a vigorous boil for 40 minutes.
When the 40 minutes have elapsed, turn the heat off and let the jars sit for five minutes.
Remove to a wooden board and allow to cool, 8-12 hours, or overnight.
Test seals by removing rims. You should not be able to pull off lids with your fingers. If seals come off easily, they have failed. Discard tomatoes. See Seal Failures, above, in post.
Label and store up to two years in cool, dark cupboard.