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What should I do if the lids seal before I get the jars into the canner for processing?

If lids seal ("pop") before jars go into the canner, the jars must still undergo the normal processing required for that product. A "seal" that forms before processing is very weak and the exhausting of air and a complete vacuum has not occurred. Processing will allow the formation of a complete vacuum which is necessary to insure a proper seal. To help eliminate the problem of a seal forming before processing, work as rapidly as possible to get filled jars into the boiling-water canner or steam pressure canner. Be sure to fill and cap only one jar at a time. 


Source: MSU "Hot Lines" #81-9




Last update: Tuesday, May 05, 2009




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