Why Copper Kitchenware Needs A Protective Lining - Tasting Table

"However, copper cannot do the job without a good lining. While copper is prized both for its utility and its beauty, it usually comes covered with a different type of metal for protection. In the past, it was commonly tin, and in more recent times stainless steel has become the standard - although both are still available for purchase. But if copper is such an excellent cooking material, why bother with the lining at all?"

"The leaching of copper into food happens because copper is reactive. When acidic ingredients are exposed to copper, they draw copper into the food. That's a big problem because acidic ingredients like tomatoes, vinegar, and lemon juice are very common additions to recipes, and because ingesting copper can be harmful. It's also why you shouldn't put copper cookware in the dishwasher. Yet, copper is a great cooking material because it heats up and cools down very quickly."

"Tin was the original copper kitchenware lining because it is easy to shape and adheres to copper very easily. Beyond being nonreactive, it also happens to be naturally non-stick as well. But tin has its own issues. It has a low melting point of only 450 degrees Fahrenheit, and it is not very durable in general. Over time the tin lining on copper kitchenware breaks down and gradually exposes the copper underneath,"

Copper cookware requires a protective lining because copper is reactive and can leach into acidic foods such as tomatoes, vinegar, and lemon juice, posing health risks. Linings historically used tin because it shapes and adheres easily and is naturally nonstick, but tin has a low melting point (about 450°F) and lacks durability. Modern copper cookware commonly uses stainless steel linings for greater durability and resistance to leaching. Copper offers superior heat responsiveness and even distribution, allowing precise temperature control and rapid searing. Copper cookware should not be put in the dishwasher because of potential damage and increased leaching risk.

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