Many people take food expiration dates with a grain of salt. After all, grocery stores like to play it very safe, usually saying food should be tossed before it has actually gone bad—and that's wasteful. Now, an enterprising design student from London has invented a surefire way to show when it really is too late to eat that steak.
It's called Bump Mark, and the concept is simple: The label itself is a living, decaying thing that goes bad along with your food. When the small, triangular label is first applied to a package, it contains a gelatin layer atop a ridged plastic sheet. Because gelatin is a protein, it will decay at the same rate as other protein-based foods in response to the surrounding environment. As gelatin breaks down, it becomes liquidy. So when things are getting dire inside the packaging, you'll be able to feel the ridges that were once hidden beneath the solid layer of jelly.
The next step is to find a way to produce the labels on a large scale and develop a plant-based layer for produce and the like. As Bump Mark's designer, Solveiga Pakstaite, says, the label is a simple, tactile way to know the condition of fresh food, and it's a lot more accurate than a printed number. If these living expiration dates come to a grocer near you, trust the bumps. If you decide to keep that chicken way after the jelly's gone, that's all on you.