Olive Fruit Selection through AI Algorithms and RGB Imaging

Foods. 2022 Oct 27;11(21):3391. doi: 10.3390/foods11213391.

Abstract

(1) Background: Extra virgin olive oil production is strictly influenced by the quality of fruits. The optical selection allows for obtaining high quality oils starting from batches with different qualitative characteristics. This study aims to test a CNN algorithm in order to assess its potential for olive classification into several quality classes for industrial purposes, specifically its potential integration and sorting performance evaluation. (2) Methods: The acquired samples were all subjected to visual analysis by a trained operator for the distinction of the products in five classes related to the state of external veraison and the presence of visible defects. The olive samples were placed at a regular distance and in a fixed position on a conveyor belt that moved at a constant speed of 1 cm/s. The images of the olives were taken every 15 s with a compact industrial RGB camera mounted on the main frame in aluminum to allow overlapping of the images, and to avoid loss of information. (3) Results: The modelling approaches used, all based on AI techniques, showed excellent results for both RGB datasets. (4) Conclusions: The presented approach regarding the qualitative discrimination of olive fruits shows its potential for both sorting machine performance evaluation and for future implementation on machines used for industrial sorting processes.

Keywords: CNN model; colour calibration; conveyor belt; machine learning; olive classification.

Grants and funding

This research was funded by the Italian Ministry of Agriculture (MiPAAF), grant number INNOLITEC, D.M. 37067/2018; AGRIDIGIT, DM 36503.7305/2018 of 20 December 2018.