I can never tell how ripe fruits are until I've taken a bite, but now help is at hand.
Scientists have measured the ripeness of apples using a technique called biospeckle. It involves shining a helium-neon laser on an apple's surface and looking at how the light reflects. Small imperfections on the apple's smooth skin cause the laser to bounce irregularly, producing a grainy appearance that changes as the apple ripens.
This technique could help farmers better predict how long fruits can be stored.