Canning whole tomatoes gives home cooks a wide variety of ways to use them. Whole canned tomatoes can later be cooked down into tomato sauce that is either chunky or smooth. The tomatoes can also be chopped down and used in salsa dishes. Tomatoes are the most popular item canned in home kitchens in the United States, and the reason is because tomatoes are easy to can and are so versatile in the kitchen.
Choosing and Preparing Tomatoes
Choose tomatoes that are free of disease and signs of rot. For best flavor, use only tomatoes that are ripened on the vine and process them within the first two to three hours after picking or purchasing. You need roughly 13 pounds of tomatoes to fill 9 pints and 21 pounds of tomatoes to fill 7 quarts. Begin by washing the tomatoes. Dip them in a pot of boiling water for 30 to 60 seconds, or until their skins split. Carefully remove from the boiling water and drop into a bowl of cold water. When cool enough to handle, slip off the skins and remove the cores with a paring knife.
To safely can tomatoes, acidity needs to be increased to a pH of 4 to 4.6. When canning pint sized jars of whole tomatoes, add 1 tablespoon lemon juice, 1/4 teaspoon citric acid, or 2 tablespoons of vinegar to each jar before adding the tomatoes. For quart sized jars, add 2 tablespoons bottled lemon juice, 1/2 teaspoon citric acid, or 4 tablespoons of vinegar to each jar before adding the tomatoes. Salt does not need to be added to canned tomatoes, but it can be used to improve the flavor of the tomatoes and to protect their color while canning.
Raw or Hot Packed
To raw pack tomatoes, fill clean jars with prepared tomatoes, leaving 1/2-inch headspace. Fill the jars with hot, boiled water, leaving the 1/2-inch headspace. Cover with new, clean lids and bands. Hot packing whole tomatoes involves boiling the tomatoes in liquid before canning them. Place the prepared tomatoes in a saucepan and cover with water. Boil the tomatoes for 5 minutes and fill clean jars with the tomatoes and the liquid. Cover with new, clean lids and bands.
Canned whole tomatoes can be processed in a boiling water canner or pressure canner. Because you have increased the acidity of the tomatoes, you can easily process them in boiling water. Fill the water canner halfway with water and fill the canning rack with the filled jars. Lower the canning rack into the water. Boiling water must cover 1 to 2 inches over the tops of the jars. Add more boiling water to the water canner as needed. Pints are processed in boiling water for 40 minutes at altitudes of 0 to 1,000 feet and for 45 minutes at altitudes of 1,001 to 3,000 feet. In a dial gauge pressure canner, raw packed tomatoes, in either pints or quarts, are processed for 10 minutes at 11 pounds in altitudes 0 to 2,000 feet. In weighted gauge pressure canners, process the raw packs at 10 pounds at altitudes of 0 to 1,000 feet and at 15 pounds for altitudes of 1,000 feet or higher. Hot packed tomatoes, in either pints of quarts, are processed in a dial gauged pressure canner for 15 minutes at 6 pounds in altitudes 0 to 2,000 feet. In weighted gauge pressure canners, process the hot packs at 5 pounds at altitudes of 0 to 1,000 feet and at 10 pounds for altitudes of 1,000 feet or higher. After the processing time is reached, allow the jars to rest undisturbed for 5 minutes before removing from a water bath and for up to an hour before removing from a pressure canner. Place the jars in a place where they will not be disturbed for 12 to 24 hours before placing them in storage.