Why are home canning jars made of glass and not metal?
I was hoping to can some food to take backpacking and looking for metal canning jars for home canning, but as far as I can see, they don't exist. Is there any reason why canning jars are made of glass? Metal seems like it would be lighter and sturdier.
Best Answer
Metal may be lighter and sturdier, but glass is nicely non-reactive and easily cleaned for re-use. It's also easier to see what it looks like inside without breaking the seal, to see if there is something that doesn't look right. It's a lot easier to do safely in home environments.
I'm not sure if the difference in the thermal properties of the metal ring vs the glass lip are important in water bath canning (e.g., the ring expanding more than the glass).
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What are advantages of glass can for canning?
The advantages of preserving foods in glass jars are obvious. The material glass is tasteless and resistant to all the salts and acids (vinegar) that are used in the food industry. Because of these properties glass jars are particularly well suited to semi-preserves such as salted fish and pickled products (Rollmops.Can any glass jar be used for canning?
Food may be canned in glass jars or metal containers. Metal containers can be used only once. They require special sealing equipment and are much more costly than jars. Regular and wide-mouth Mason-type, threaded, home-canning jars with self-sealing lids are the best choice.Are Mason jars non toxic?
This coating, while meant to be protective, is not entirely safe. These chemicals are known hormone disruptors that leach into food that comes into contact with it, and even the BPA substitutes are not viewed favorably.What is special about Mason jars?
Mason jars have a two-part top \u2015 a lid with a rubber ring on the underside, which creates a vacuum seal (which is so integral for safe canning), and an outer band with screw threads that are reusable. The lids can only be used to seal once, but the jars and bands can be reused many times.The Metal Spoon Test (How to tell if your jars sealed)
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