Kilner jars are a classic preserving tool, known all over the world.
The original Kilner jar
The Kilner jar and bottle company was founded by John Kilner in 1842 in Yorkshire. Upon his death in 1857, Kilner’s four sons took over the business, followed later by their sons. The business thrived and expanded, winning various awards and international recognition. The pressure seal system was created and patented towards the end of the 19th century and has been in use ever since. In 1937 the company sold the patent rights to the Kilner jar and the similar Mason jar, also made by Kilner, to the United Glass Bottle company – an American firm. The Rayware Group purchased Kilner in 2000 and continues to produce the jars and develop new and modern variations on the theme.
How does the Kilner jar work?
The traditional system uses a screw top with a rubber seal, which is processed in a hot water bath to dispel any air and create a pressure seal. This ensures no air or bacteria can enter the jar to spoil your preserves once the seal has been created.
After sterilising your Kilner jars, fill them with your jam while it is still warm as part of the sealing process. Fill to the bottom of the jar neck and gently tap the jar on the work surface to disperse air bubbles. Wipe around the neck of the jar to ensure it is clean, then close your jar. You can use the Kilner disc and screw band jars, screw top jars and clip top jars in the same way for preserving, as all create the necessary pressure seal when correctly used. You can then create a pressure seal using the water bath method, which means putting the jars in a large pan filled with water and boiling for about 30 minutes. Remove the jars from the pan with a jar lifter and allow to cool for 24 hours. The next day, check that the sealing process has been successful. A proper seal will preserve homemade jams, chutneys and curds for up to six months when stored in a cool, dark place.
The Kilner range of today includes clip top jars, handled drinking jars, screw top and clip top bottles, push top knobstopper jars, home brewing kits, and accessories for preserving and home brewing.