Assessment of mechanical damage on apples with image analysis.

The aim of the study was to determine oxidation area and skin colour change at the damaged apples by using image analysis technique. Golden Delicious, Granny Smith and Stark Crimson apple varieties were examined with a special pendulum unit which was developed for the impact test. Plastic and wood materials were used as impact surface, and apples were dropped from different heights to the impact surface. Impact to each apple occurred perpendicular to impact surface from predetermined heights. After the impact test, colour change of damaged regions and oxidation areas of each sample were estimated by using a digital camera. Colour measurements were done with a colourmeter based on L*, a*, b* measurement system. The oxidation areas were evaluated clearly after these processes. The results of the impact tests indicated that response to impact bruising is dependent on flesh firmness and the impact height as well as apple variety.