Your Moscow Mule may not come in a copper mug anymore in Iowa
Serving Moscow Mules in a solid copper mug is against FDA food code.
An advisory bulletin from Iowa’s Alcoholic Beverages Division said that the popularity of Moscow Mules spawned questions about whether it was safe to use copper mugs with the drink.
Drinks or foods that are under a 6.0 pH are prohibited from coming into contact with copper, according to the federal Food and Drug Administration’s Model Food Code. A traditional Moscow Mule’s pH “is well below 6.0.”
Other examples of foods that have a lower-than-acceptable pH are vinegar, fruit juice and wine.
“High concentrations of copper are poisonous and have caused foodborne illness,” read the bulletin’s Public Health Reasoning. “When copper and copper alloy surfaces contact acidic foods, copper may be leached into the food.”
While Moscow Mules can’t be served in a solid copper mug, they can still be served in mugs that have another metal as an interior, like nickel or stainless steel.