This is accomplished through the use of ultraviolet light that illuminates the essential oils in the rinds of rotten oranges, but this is a slow process as the workers can only stay so long being exposed to UV light. However now there is a way that allows machines to do the same job automatically.
Scientists from Spain’s Valencian Institute of Agrarian Research have created a machine that will scan the fruits using UV light, and through image analysis techniques, it will be able to tell which fruits are bad and which are all right. It even goes as far as sorting the fruits according to aesthetic appeal. We’ll have to wonder if our fruits will start getting more expensive now thanks to this new process of sorting.