A newly developed method based on surface physicochemical proprieties, for measuring the maturation level of olive fruit

The maturation process is an important determining factor to initiate the fermentation process in olive fruit. Level of maturation classically determined by the color of the olive fruit. In this study, we aim to develop a measurable criterion based on physicochemical properties and surface roughness of two important olive varieties grown in Morocco. The hydrophobic/hydrophilic properties and the electron donor-acceptor character of the olives were calculated. The obtained results showed a very clear change in the electron donor character and the surface roughness of the two studied varieties. This change depended on the degree of maturity and the nature of the cultivar. The electron donor character decreased (two times) with an increasing degree of maturity for the Arbequina, contrary to the Picholine variety, which showed a significant increase (4 times). Surface roughness increased 10 times for the Arbequina and decreased 5 times for the Picholine as maturity progressed from the green to the black stage. These findings may be useful in the management/prediction of the process of table olive fermentation.