Should You Throw Away Rusty Mason Jar Lids?

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Mason jars play an important role in the kitchen. Sure they help preserve some of our favorite foods, but they have other uses, too. You can use Mason jars inside your utensil drawer to organize culinary spoons and spatulas or even create a Mason jar salad with layers of ingredients. However, those metal lids can spark quite a conundrum. When they start to get rusty, you might wonder if it is time to toss them. The answer is: It depends on just how rusty they are and how you are planning to use them.

A Mason jar lid can be rusty and still be usable as long as it isn't bent, warped, structurally damaged, or being reused for canning purposes. Sadly, while the jar is designed for reuse, most of the lids are not. Most makers of this screw-on top with a metal disk only guarantee it will seal one time, thus rendering them unsafe for future canning use. However, if you are just planning to use the canning jar and lid for other organizational purposes, a rusty lid is not a reason to toss it. 

What causes a Mason jar lid to rust? First and foremost, they are made of metal which is prone to rust. But there are several factors that can lead to a corroded canning lid — improper prepping, a strong concentration of salt and acid, and not storing the lids properly before use can all lead to a rusted lid. However, rust on a lid doesn't mean you need to immediately get rid of a canned good. As long as it is only on the lid and the vacuum seal is intact, the food inside should be fine.

Prevention starts with drying wet lids after you wash them. Unused lids are generally good for up to five years. However, if you do find rust on your Mason jar lid, try cleaning it with some baking soda and lemon, and scrubbing away all those unsightly rust spots. If you do not have any lemon, vinegar will work, too. Rinse and dry thoroughly, and you are in business to use the metal band or ring to make copycat McDonald's egg McMuffins at home or stack the jar with a grits-based meal for an easy make-ahead breakfast or lunch.

However, if you feel your lids are too rusty, and you've decided to get rid of them, you can easily buy replacement sets of Mason jars on Amazon or even just buy packs of replacement lids, like these Dalzom-branded ones that fit regular Mason jars.