Kilner Jars

[mthompson]

What exactly is a Kilner Jar?

[paulz]

It's a glass [quite] thick jar, with with either a tin lid that's held in place with a screw ring other varieties have a hinged metal ring that clips into place. A rubber ring make the seal. You use them for preserved stuff - jam, pickles etc, Generally hot food goes into a hot sterilzied jar. Once sealed, a vacuum forms [on cooling] keeping the contents from going off see - http://www.fixandmend.co.uk/Chulmleigh/36103[1].jp
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