Monitoring the growth and maturation of apple fruit on the tree with handheld Vis/NIR devices

Modern computer-controlled fruit grading and sorting facilities, with non-destructive Vis/NIR technologies based on transmission spectroscopy are now common. The main applications, at least in apple sorting, are not only to identify internal browning disorders in fruit after storage but also to grade out fruit with physiological conditions like watercore (fluid filled, glassy looking areas within the fruit flesh) in the period after harvest but before long-term storage. Usually, both these types of internal flesh disorders are not visible from the outside of the apple; thus, high-speed Vis/NIR non-destructive sorting of the individual fruit has been a considerable advancement for the fruit industry to ensure the supply of good quality apples to the end consumer.