WILD OLIVE (OLEA EUROPAEA L.) SELECTION FOR QUALITY OIL PRODUCTION

ABSTRACT One hundred and fifty accessions belong to six wild olive populations from Tunisia were analyzed using fruit pomological traits and oil chemical characteristics. Analysis of variance revealed significant differences among olive accessions for the main studied parameters, indicating a high degree of variability among oleasters. Cluster analysis revealed no clear relationships between accessions according to their geographical origin. Among the screened oleasters, three stand out for their interesting oil parameters, as compared to traditional varieties with high oleic and low linoleic acid contents, high triolein level, large total phenol content, high oxidative stability and high oil content. ZI2 had the highest values of oleic acid (78.5%), whereas H3 was noteworthy for its higher content of phenolic compounds (435.3 mg/kg). Accordingly, oil from H3 presented the highest oxidative stability (83.5 h). A significant relationship was observed between phenolic compounds and oxidative stability. PRACTICAL APPLICATIONS The identification of new cultivars and their oil composition is a key point in the improvement of olive oil production. This is the first study of chemical composition of virgin olive oils from wild olives. The paper is a study on the quality characteristics of olive oils obtained from wild olive trees growing in Tunisia to define new cultivars well adapted to Tunisian environment and yielding high quality oils. Although the study was carried out in Tunisia, it might be applied to other countries with wild olive trees, in order to contrast productivity and oil quality with those resulting from native cultivars and transplanted foreign varieties.