What is processing?
Processing is heating food in closed jars to insure destruction of microorganisms and to exhaust air from the jars to create a vacuum. This will insure that canned food will remain unspoiled and safe to eat.
Acid foods (foods with a pH less than 4.6, such as fruits, pickles, and preserves) are safely processed in a boiling water bath. Low acid foods (such as vegetables and meat) require processing at a higher temperature by use of a steam pressure canner. The times required to insure an adequate process are specified in canning directions for each food. Reliable sources for canning directions include current University Extension publications and USDA bulletins.
Barbara Willenberg, Nutritional
Sciences, University of Missouri-Columbia
Last update: Tuesday, May 05, 2009