Sometimes you can’t trust your eyeballs — what looks like a perfectly good apple could in fact be hiding a dark, rotting and festering secret at its core. So it would be kind of neat if someone were to say, invent an edible sensor for food that you could scan with your smartphone to see if it’s safe to eat.

Someone is working on that, turns out: Professor Fiorenzo Omenetto at Tufts University is on the task with his team of researchers, says WBZ News in Boston.

“Think of it as a tattoo,” he says, while describing a little square that contains thousands of tiny antennas. What he calls a tattoo is made up of silk and gold and would stick to any type of food.

The process of making the tattoos takes silkworm cocoons and boils them down into an edible plastic. Then gold is affixed to the plastic in the shape of tiny antennas that can detect if milk is spoiled, or if a bag of salad has e-coli.

“The idea is that, for example, if you have a build-up of bacteria then the antennae will be able to report whether the food is safe to eat or not,” says Omenetto.

If these gadgets work out, they could be ready for use in three to five years and save you money –¬†how many times have you tossed something not knowing if it’s safe to eat or not?

And in the meantime, you can always check out Consumer Reports‘ guidelines for when to toss condiments.

Local Invention Could Tell If Food Is Fresh, Save Money [WBZ Boston]

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