Kilner jar

Preserved lemon in a clip top jar, 4 years old

Kilner jar refers to a type of glass jar used for the preservation of food, named after its inventor, John Kilner. The Kilner jar was first created in the 19th century in England and has since become synonymous with home canning and preserving techniques. These jars are distinguished by their unique sealing mechanism, which typically consists of a glass or metal lid, a rubber seal, and a metal screw band. This design allows for an airtight seal, which is crucial for the preservation of foodstuffs, preventing the ingress of air and the growth of microorganisms that can lead to food spoilage.

History

The Kilner jar was invented by John Kilner in England in the 1840s, during a time when food preservation was becoming increasingly important due to the lack of refrigeration. The original design was made of glass and featured a simple yet effective sealing method that was revolutionary at the time. The Kilner family's business, Kilner Brothers, initially produced the jars, which quickly gained popularity for their reliability and effectiveness in preserving food.

Design and Usage

The traditional Kilner jar design includes a two-part lid system: a replaceable vacuum seal and a metal screw band. The vacuum seal is made of rubber or silicone and sits on the rim of the jar, while the metal screw band secures the seal in place during the canning process. Once the jar is sealed and the contents are processed through boiling or other methods, the cooling process creates a vacuum within the jar, further securing the seal and preserving the food inside.

Kilner jars are used for a variety of home canning and preserving tasks, including the storage of fruits, vegetables, jams, honey, and pickles. They are also popular for fermenting foods like sauerkraut and for making kombucha, a fermented tea.

Modern Variations

Today, Kilner jars come in various sizes and designs, including those with clip-top lids, which use a glass lid and a metal clip for sealing, offering an alternative to the screw-top design. These jars are not only functional for food preservation but have also become popular in home decor and as serving vessels in restaurants and cafes.

Care and Maintenance

Proper care and maintenance of Kilner jars are essential for ensuring their longevity and effectiveness in food preservation. It is important to inspect the jars and their components for any signs of wear or damage before each use. The rubber seals should be replaced regularly to maintain an airtight seal. Kilner jars and their components are generally dishwasher safe, although it is recommended to hand wash the rubber seals.

Environmental Impact

Kilner jars are considered an environmentally friendly option for food storage and preservation. Their durability and reusability reduce the need for disposable packaging and contribute to a reduction in plastic waste. By enabling home preservation of food, Kilner jars also help reduce food waste, allowing for seasonal produce to be enjoyed year-round.