Zap a lemon with a laser and you can find out it ‘s ready for the table Forget squeezing to see it it’s ripe - Just look at the way it glow in the dark. That’s the message from Portugal, Where scientists have discovered that, when ripe, fruits such as apple and kiwifruit fluoresce brightly it they are Zapped with a laser. They hope the effect will provide a way to tell the ripeness of fruit on an industrial, without anyone having to roach it. (5)