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Quick Answers



Some of the foods I canned in the boiling-water canner spoiled. Why?

Any one or more of the following may cause canned food to spoil when water bath processed:


  • Inadequate heat penetration as a result of not having water at rolling boil when jars placed in canner.
  • Not having water 1 inch or more above tops of all jars throughout entire processing time.
  • Not keeping water at rolling boil entire processing time.
  • Not adjusting for altitude.
  • Not following time table carefully for product being canned.
  • Produce coming unsealed because standard jars and lids not being used.
  • Using cracked or chipped jars.
  • Not using new flats.




Barbara Willenberg, Nutritional Sciences, University of Missouri-Columbia




Last update: Tuesday, May 05, 2009



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