If scientists from Purdue University have it their way, sour grapes may soon be a thing of the past. By adapting and simplifying the medical technology known as magnetic resonance imaging (MRI), they have developed a fruit-ripeness sensor that may benefit growers, food processors, and consumers. Their portable machine uses magnetic fields to detect the sugar level in fruits and vegetables--which is usually the best indication of ripeness.
Purdue engineer Gary Krutz foresees fruits and veggies sporting "sell-by" stickers similar to those on dairy products. Since an estimated 20% of all produce is thrown away because of overripeness, the sensor could reduce waste by helping farmers and grocers determine the optimum time for harvesting and selling produce. Researchers plan to test the $20,000 machine at an Indiana supermarket within a year--and to develop a similar instrument for gauging the fat in foods.