Pressure canning is the only recommended method for canning meat, poultry, seafood, and vegetables. The bacterium Clostridium botulinum is destroyed in low-acid foods when they are processed at the correct time and pressure in pressure canners. Using boiling water canners for these foods poses a real risk of botulism poisoning.
Low acid foods lack the acidity needed to inhibit the growth of bacteria and spores that can survive boiling water temperatures (212ºF.) A temperature of 240ºF is needed to destroy bacterial spores. This temperature can only be reached in a pressure canner; at 10 pounds pressure or higher.
Two reliable sources for additional information are Missouri Families and the National Center for Home Food Preservation.
Contributor: Maude Harris, EdD, Nutrition and Health Education Specialist, University of Missouri Extention, firstname.lastname@example.org