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Canning Tomatoes

Canning Tomatoes
Author: Wendy Solum
Prep time:
Total time:
Serves: 30-32oz jars
3 half-bushels of tomatoes, 2 people, about 4 hours | Yield: about 30 32oz jars. You will need 1/2 tsp of canning salt for each 32oz jar.
  • Tomatoes
  • Canning salt
  1. <h2>What you may need</h2>
  2. Lids (Use new lids each year)
  3. Collars (may be reused from year to year until really rusty or bent). Store the collars on the jars.
  4. Jars (32 oz mason jars) normal sized as opposed to wide mouth are preferred
  5. pot to boil the lids and collars in. This can be a smaller pot.
  6. large stock pot or Dutch oven to blanch the tomatoes
  7. large stock pots or Dutch ovens to cook the tomatoes (may make do with one)
  8. large stock pot or Dutch oven to fill with ice water to cool down the tomatoes. Your kitchen sink will do also, but depending upon your setup, you may need the sink to continue to wash jars, etc.
  9. A paring knife and a strainer for coring and skinning tomatoes
  10. A mesh strainer for plucking hot tomatoes out of boiling water
  11. A wide mouth funnel for filling the jars
  12. Tongs and/or a serving fork for fishing out the lids and collars
  13. A ladle for filling the jars
  14. Crock pots work nicely for lids if you run out of room on the stove top
  15. Paper towels for wiping dry the mouths of the jars and the lids
  16. <h2>Prepare</h2>
  17. Set up an area for filling jars. You may want to surround the area with paper towels and/or place a towel underneath the “jar filling area” so it sops up the mess you are going to create.
  18. You will need an area to peel and core tomatoes. This is best done over the sink. Do what works best for you.
  19. Set oven to 200.
  20. <h2>Start canning!</h2>
  21. Wash the jars in hot water. Rinse and place into oven. This will dry them and keep them sterile.
  22. Separate and drop lids and collars into boiling water. (Tip-lids first, then collars; that way the lids don’t fall into the collars. Also one lid up, one down; that way they are less likely to nest. Argggh!!)
  23. Blanch tomatoes in boiling water until the skin cracks-about 30-60 seconds. Some may not crack.
  24. Place tomatoes into ice water until cool enough to handle.
  25. Peel and core tomatoes. Cut into quarters and place into a pot on the stove.
  26. Simmer at a med temp and cook down to a desired consistency. Use a spoon or masher to occasionally mush them up a bit. Do not let them stick to the bottom of the pan.
  27. Remove sterile jars from oven with a sterile utensil (tongs) and place on prep surface.
  28. Fill the jars with prepared tomatoes using a funnel and a ladle, leaving ½” headspace in the jar.
  29. Add 1 tsp of canning salt.
  30. Wipe the mouth of the jar with a clean paper towel to remove any tomato residue or moisture.
  31. Remove lids and collars from boiling water (using a sterile utensil of course). Lids must be clean and dry to create a good seal so use a clean paper towel to dab off any excess water from the lids.
  32. Top each jar with a lid (are they clean and dry?). Keep them sterile; do not touch areas that may come into contact with the tomatoes.
  33. Screw on a collar until snug, not too tight.
  34. Move to a separate location for cooling and cover with a towel (this allows them to cool slowly).
  35. When finished, leave jars, undisturbed overnight, with the towel covering them.
  36. You may hear some popping noise coming from the jars overnight. This is normal; the lid gets sucked inward, creating a tight seal, causing the popping noise. In the morning, check to make sure the jars are in fact, sealed tightly. The lid should be con-caved and not move when pressed. If you can push them in they do not have a good seal.
  37. Tighten the collars once more (they loosen up a bit during the cooling process).
  38. Label them and store the jars in a dark, cool, dry place. Shelf life is about 1 year to 18 months. After that, use at your discretion.