Extension Logo
Extension Logo
University of Minnesota Extension

Canning Minnesota tomato mixture

Food safety starts with cleaning!

Wash hands for 20 seconds

  • Wet hands under hot running water. Add lots of soap.
  • Rub and wash back of hands, wrists, between fingers and under fingernails for 20 seconds.
  • Rinse well under running water.
  • Dry with paper towels.
  • Use paper to turn off the water faucet.

Clean and sanitize sink and counter tops

  • Wash counter tops and prep sinks with hot soapy water.
  • Fill squirt bottle with 1 quart water. Add 1 teaspoon of unscented regular chlorine bleach or ¾ unscented ultra (6% sodium hypochlorite) chlorine bleach. Or use commercially prepared cleaner and follow directions on label.
  • Spray counter tops and sink with bleach solution. Let air dry.
  • Wash hands.

Clean as you go

  • Wash dishes, utensils, cutting boards, etc. in hot soapy water.
  • Let air dry.
Canned Minnesota tomato mixture.


  • 12 cups tomatoes (approximately 32 medium round tomatoes)
  • 1/2 cup chopped green pepper
  • 1 cup chopped celery
  • 3 teaspoons canning salt
  • 1/2 cup chopped onion
  • Bottled lemon juice or citric acid

Note: Do not increase the amount of pepper, onion, or celery. Doing so will alter the acidity level and make it unsafe for canning.

Canning directions

1) Prepare jars - yields 6-7 pints; double recipe for 6-7 quarts

  • Inspect canning jars for chips and cracks.
  • Wash jars in hot soapy water, rinse well.
  • Fill the canner half full with clean warm water.
  • Center the canner over the burner and preheat the water to 140°F for raw-packed foods and to 180°F for hot-packed foods. Use a food thermometer to monitor temperature.
  • Put jars into canner so they fill with water.
  • Prepare tomato mixture while preheating jars.

2) Wash tomatoes

  • Tomatoes - disease free, firm. Do not use soft, overripe, decayed or tomatoes harvested from dead or frost-killed vines. Doing so will alter the acidity level and make it unsafe for canning.
  • Wash tomatoes under running water (10 degrees warmer than tomatoes). Scrub gently with clean hands and a soft cloth.

3) Blanch, peel (optional if canning with skins)

  • Bring a pot of hot water to boil.
  • Put tomatoes in boiling water for 30 to 60 seconds or until skins split.
  • Dip tomatoes in a pot of cold ice water.
  • Remove skins with knife.

4) Core and prep tomatoes

  • Remove cores. Don't use bruised or decaying tomatoes. Quarter tomatoes.
  • Place in large cooking kettle.

5) Wash and chop pepper, celery and onion

  • Wash pepper, celery and onion under running water. Scrub gently with produce brush.
  • Chop pepper, celery and onion.

6) Heat tomato mixture

  • Add chopped pepper, celery, onion and salt to kettle of tomatoes.
  • Stir.
  • Simmer for 10 minutes.

7) Prepare lids

  • According to research done by Jarden Home Brands quality assurance team, pre-heating metal canning lids is not necessary. To prepare lids, wash them with soapy water and keep at room temperature until ready to use.

8) Fill jars

  • Use jar lifter to remove jars from canner pouring water from jars back into the canner.
  • Place hot jars upside down on a towel or cake cooling rack.
  • Add 1/4 teaspoon of citric acid per pint jar or 1 tablespoon bottled lemon juice per pint. Add 1/2 teaspoon citric acid per quart or 2 tablespoons bottled lemon juice to each quart jar.
  • Ladle tomato mixture into hot jars using a funnel (jar filler).
  • Fill to 1/2 inch from top of jar (this is called headspace).
  • Insert a plastic utensil to remove trapped air bubbles. (Don't use metal as it can scratch the glass increasing risk for breakage.)
  • Re-adjust headspace to 1/2 inch if needed by adding more tomato mixture.
  • Wipe top of the jar rim with a damp clean paper towel.
  • Remove lid from saucepan with tongs or lid wand and place on jar.
  • Apply screw band, finger tight. Do not over tighten

9) Load the canner

  • Place filled jars in canner one at a time using a jar lifter. Make sure the jar lifter is securely positioned below the neck of the jar (below the screw band of the lid). Keep the jar upright at all times. Tilting the jar could cause food to spill into the sealing area of the lid.
  • Add more boiling water, if needed, so the water level is at least two inches above the jar tops.
  • Turn the heat setting to its highest position, cover the canner with its lid and heat until the water boils vigorously. Reduce heat to maintain a gentle rolling boil.
  • Set timer. Process pints for 40 minutes and quarts for 50 minutes.
  • Add more boiling water during the process, if needed, to keep the water level 1-2 inches above the jar tops.
  • If the water stops boiling at any time during the process, turn the heat on its highest setting, bring the water back to a vigorous boil, and begin the timing of the process over from the beginning (using the total original process time).

10) Unload the canner

  • When timer rings, turn off heat and remove cover.
  • Wait 5 minutes before removing jars to prevent 'spill overs' and ensure good seals.
  • Using a jar lifter, remove the jars one at a time, being careful not to tilt the jars.
  • Place jars directly onto a towel or cake cooling rack, leaving at least one inch of space between the jars during cooling.

11) Cool and store

  • Let the jars sit undisturbed while they cool, from 12 to 24 hours. Do not tighten ring bands on the lids or push down on the center of the flat metal lid until the jar is completely cooled.
  • Remove ring bands from sealed jars. Test seal. Press the center of the lid. It is sealed if there is no clicking sound.
  • Put any unsealed jars in the refrigerator and use first.
  • Wipe jars and lids with a wet cloth.
  • Label with name of contents and date.
  • Store in a cool, dark, dry place for up to 1 year.

Reviewed in 2018

Page survey

© 2023 Regents of the University of Minnesota. All rights reserved. The University of Minnesota is an equal opportunity educator and employer.