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After processing, I pushed the lid down to make the jar seal. Is this okay?

The lid, or flat, of the two-piece canning lid should never be checked or disturbed until 12-24 hours after processing. At this time, if a lid appears unsealed, but remains depressed when pressure is applied, it has formed a weak seal. You have two alternatives. You can refrigerate the food and use it within several days. Or, you can give the seal a tougher test:

- Remove the screwband and set the jar in a pan padded with a clean towel.      

- Lift the jar by the sealed-on flat.      

- If the seal is too weak, the weight of the jar will break it and the jar will drop and spill leaving the flat in your hand. The towel prevents the jar from breaking.      

- The spilled contents can be collected for serving or reprocessing.      

- If the flat remains attached, the seal is good.                  



Barbara Willenberg, Nutritional Sciences, University of Missouri-Columbia




Last update: Tuesday, May 05, 2009



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