How lasers can tell when an apple is perfect

Published November 04, 2015

Might want to scan that apple with a laser before eating it. (AP Photo/Czarek Sokolowski)

It can be tough to tell, without biting into an apple, whether it's unripe, just ripe enough, or its tastiest days are behind it. Fortunately, scientists in Lebanon and France are working on a new way to determine ripeness, and instead of using their teeth, they've opted for what they call a "laser biospeckle technique." Researchers shined a laser at the outside of an apple, and it revealed a speckled texture, as shown at Phys.org.

The riper the apple got, the smaller the individual speckle grains became, probably because of activity in the apple's cells, the researchers say. After the apple had passed its ideal point of ripeness, those grains started getting bigger again.

Researchers checked their work by watching the apple's production of ethylene gas at the same time; the gas is increasingly produced until a fruit is ready to eat.

As the grains got bigger again, the gas production got slower, Science reports. Researchers are working on a similar process for pears. The hope is that farmers could eventually use the process to ensure their harvest comes at just the right time, Photonics Online reports.

(While you're pondering tasty fruit, you might want to consider the Mediterranean diet, which could reportedly extend life by years.)

This article originally appeared on Newser: How Lasers Can Spot the Perfect Apple