how long to process tomatoes when canning
As each jar is filled, stand it on rack in canner of hot, not boiling, water, which should cover jars by 1 to 2 inches. (Add additional water if necessary.) Put cover on canner, and bring water to a boil. Process quarts for up to 45 minutes (40 minutes for pints) at a gentle but steady boil. Using tongs, carefully remove jars from canner and set on a wood or cloth surface, placing jars several inches apart and out of drafts.