Newsflash
Is it safe for jars to be submerged in a pressure canner?
The National Center for Home Food Preservation advises that jars should not be fully submerged in water during pressure canning. Steam is more efficient at transferring heat when jars are not submerged, as it releases latent heat when it condenses on cooler surfaces. Too much water reduces steam, slowing heat transfer and potentially causing inadequate heating inside the jar. Tested recipes are designed for steam-dominant processing, and deviating from this could affect safety and effectiveness.
Note: Regular and wide-mouth Mason-type, threaded, home-canning jars with self-sealing lids are the best choice. Always follow the recipe. Some foods (e.g., smoked fish) may require more water, so adhere to USDA guidelines for specific foods.