Tomato Basics

This information has been reviewed and adapted for use in South Carolina by P.H. Schmutz, HGIC Information Specialist; J.E. Campbell, Graduate Student; and E.H. Hoyle, Extension Food Safety Specialist, Clemson University. (New 10/01. Revised 03/05.)

HGIC 3539

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Getting Ready to Preserve

  • Select only disease-free, preferably vine-ripened, firm tomatoes with deep red color.
  • For easy peeling, dip tomatoes in boiling water for 30 to 60 seconds until skins split. Dip into cold water and slip off skins.
  • Remove cores. Leave whole or halve.

Canning Tomatoes

Quantity: 1 bushel = 53 pounds and yields 15 to 21 quarts. An average of 21 pounds of whole or halved tomatoes is needed per canner load of 7 quarts.An average of 13 pounds of whole or halved tomatoes is needed per canner load of 9 pints.

Method: To ensure safe acidity in tomatoes, add 2 tablespoons of bottled lemon juice or ½ teaspoon citric acid per quart of tomatoes to the jars. Add 1 teaspoon of salt per quart to the jars, if desired. Fill jars with raw tomatoes. Press tomatoes in the jars until spaces between them fill with juice. Leave ½ -inch headspace. Remove air bubbles. Wipe jar rims. Adjust lids and process pints or quarts using one of the following options:

  • a boiling water bath for 85 minutes.
  • a dial-gauge pressure canner at 11 pounds pressure for 25 minutes.
  • a weighted gauge pressure canner at 10 pounds pressure for 25 minutes.

Note: Times and pressures given are for altitudes up to 1,000 feet.

Freezing Tomatoes

After the tomatoes have been washed and dipped in boiling water for 30 seconds to loosen skins, core and peel them. Pack tomatoes whole or in pieces into containers, leaving 1-inch headspace. Seal, label and freeze. Use only for cooking or seasoning, as tomatoes will not be solid when thawed.

Spaghetti Sauce Without Meat

Makes about 9 pint jars.

Peel, core and quarter 30 pounds of tomatoes. Boil for 20 minutes, uncovered, in large saucepan. Press through a food mill or sieve. Sauté 1 cup chopped onions, 5 cloves of minced garlic, 1 cup chopped celery or green pepper, and 1 pound sliced fresh mushrooms (optional) in ¼ cup vegetable oil until tender. Combine sautéed vegetables and tomatoes. Add 2 tablespoons oregano, 4 tablespoons minced parsley, 2 teaspoons black pepper, 4 ½  teaspoons salt and ¼ cup brown sugar and bring to a boil.

Caution: Do not increase the proportion of onions, peppers or mushrooms. Simmer uncovered, stirring frequently until thick enough for serving.

Pour into hot jars, leaving 1-inch headspace. Wipe jar rims, adjust lids and process in a dial-gauge canner at 11 pounds pressure or in a weighted-gauge pressure canner at 10 pounds pressure: 20 minutes for pints, and 25 minutes for quarts.

Note: Times and pressures given are for altitudes up to 1,000 feet.

For more information see fact sheets HGIC 3320, Preserving Tomatoes, HGIC 3340, Preserving Tomato Sauces and Ketchup, and HGIC 3360, Preserving Tomato Products.


USDA. Complete Guide to Home Canning. Agriculture Information Bulletin No. 539. Reviewed 1994.

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This information is supplied with the understanding that no discrimination is intended and no endorsement of brand names or registered trademarks by the Clemson University Cooperative Extension Service is implied, nor is any discrimination intended by the exclusion of products or manufacturers not named. All recommendations are for South Carolina conditions and may not apply to other areas. Use pesticides only according to the directions on the label. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Follow all directions, precautions and restrictions that are listed.