Canning soup at home is an excellent way to preserve your vegetables with or without small portions of meats or seafood. The key to canning a safe, high quality soup is to follow directions provided by a reliable science-based source like USDA or the University of Wisconsin-Extension.
Vegetable-based soups are usually mixtures of low-acid ingredients and they need to be pressure canned by a process that has been developed by research methods known to control for botulism food poisoning. Botulism is a potentially fatal foodborne disease. Spores of the organism (Clostridium botulinum) that causes botulism can survive normal cooking temperatures and times. The extra heat in pressure canning is needed to actually destroy the spores so when the closed jar sits at room temperature in storage, the spores will not grow and produce the deadly botulinal toxin.
There is only one version of pressure canning directions for home canned soups available from USDA and found on the website for the National Center for Home Food Preservation. The USDA procedure allows you to add your choice of vegetables, dried beans or peas, meat, poultry, or seafood. It does not allow you to include noodles or other pasta, rice, flour, cream, milk or other thickening or dairy ingredients. Directions for this soup need to be carefully followed, or an unsafe product may result.
If dried beans or peas are used, they must first be fully rehydrated (for each cup of dried beans or peas add 3 cups of water, boil 2 minutes, remove from heat, soak 1 hour, heat to boiling, drain). The recipe should not include items such as summer squash, unpeeled potatoes, or mashed winter squash – an unsafe product may result.
Each vegetable should be selected, washed, prepared and cooked as you would for canning a ‘hot pack’ according to USDA directions for canning vegetables and tomatoes.
If meat is added, it should be covered with water and cooked until tender, then cooled and the bones removed. Next, all the prepared ingredients should be cooked together with hot water, broth or tomatoes, to boiling, and boiled for 5 minutes. Salt can be added to taste, if desired. Do not fully cook the soup before filling jars; the canning process completes the cooking at the same time it eliminates harmful microorganisms.
A very important step in these procedures is that jars should only be filled halfway with the mixture of solids. The rest of the jar is filled with the hot liquid leaving 1-inch headspace. The recipe must be processed in a pressure canner, even if it tomato-based. Be sure to adjust for elevation for locations above 1,000 feet. Safe preserving! Barb
Filed under: Canning (general), Vegetables | Tagged: canning, soup, vegetables | Comments Off