Among the analysed phenols, only hydroxytyrosol, caffeic acid and ferulic acid always increased during fermentation, while the others increased up to 90–120 days and then decreased.
The Principal Component Analysis (PCA) performed on pH and phenol values highlighted three clusters of olive cultivars.
Throughout the brining period, lactic acid bacteria were always present while staphylococci and coliform bacteria disappeared after 30 and 90 days, respectively.