Most of the maturity measuring techniques used for commercial tree fruit production are destructive, fruit is wasted. The search for easy to use non destructive fruit maturity technology for fresh fruit has been underway for a very long time. Recently, several devices to assist in determining some of the commonly used fruit quality parameters, such as firmness, soluble solids content ,titratable acidity, dry matter content and skin color, have been introduced to the market.
There are several competitors, the apparent leader at the moment is the DA Meter made by the Turoni company in Italy. This rather expensive tool has produced some impressive results.
This instrument that measures the chlorophyll’s content in a fruit to predict maturity development of fruit. There are versions for many types. The DA Meter is being used here in British Columbia , Washington State, Nova Scotia and many other areas around the world.
The primary use of this type of technology is for the prediction of harvest times for large scale fresh fruit production. It is particularly useful for long hold (controlled atmosphere or CA) storage of apples.
This Good Fruit Grower article published in 2016 describes several of the devices and techniques available to determine fruit maturity