What causes the shiny, rainbow-colored effect on some sliced meats? And is it safe to eat?
This effect is known as iridescence. It is commonly found in animal muscle tissue before and after processing, and most often appears as a shiny, almost metallic green or orange/red color. Cooked and cured meats often result in a brighter color than uncured meats, making the iridescence more visible. Though some have suspected a connection between the use of phosphates and iridescence, there is currently no data to support that idea. The causes are still not entirely known, but once it appears, there is nothing that will remove or reduce the visible effect. We do know, however, that iridescence is a naturally occurring factor and does NOT affect the quality or safety of the meat in any way. It does not indicate spoilage or degradation of freshness. You can feel confident that consumption of any of our products that might exhibit this iridescent effect is perfectly safe, and should have all the same flavor, juiciness and tenderness that you find in all of our fine products.