Scientists Are Developing a 3-D-Printed ‘Smart Cap’ That Can Tell When Food Is Spoiled

Engineers at Berkeley are perfecting a 3D-printed ‘smart cap’ that uses built-in sensors to tell when food is going bad


Imagine a world where your fears of drinking curdled milk would never come true.

Food preservation technology is advancing quickly. Last year, we reported on smart tags that change color as your food gets progressively closer to expiration, and now scientists are working on a smart cap (for your carton of milk or orange juice, for instance), that can sense when food has gone bad.This product, currently in development at the University of California, Berkeley, senses impending expiration with the help of 3-D-printed embedded sensory technology.

The smart cap contains a reservoir where a small sample of the milk can be sampled and tested with a built-in conductor that “reads” the bacterial growth inside the milk. Until now, 3-D-printed technology could not work with electric circuits, because the preferred 3-D-printing material is incompatible with electric currents, but researchers found a way around that by using plastic and wax hollow tubes that they filled with conductive metals.


“Our paper describes the first demonstration of 3-D-printing for working basic electrical components, as well as a working wireless sensor,” senior author Liwei Lin told The Star, an Indonesian newspaper. "One day, people may simply download 3-D-printing files from the Internet with customized shapes and colors and print out useful devices at home."