Rainbow Sheen on Deli Ham: Is It Safe or a Sign of Spoilage?
You open a newly bought package of deli ham and pause—there it is. A glossy rainbow shimmer sweeping across the slices, flashing hints of green, blue, and purple. It looks unnatural, almost alarming, and for many people it’s enough to question whether lunch should go straight into the trash.
The good news: this effect, known as iridescence, is usually harmless. Understanding why it happens—and how to spot real spoilage—can save both food and worry.
