Ines Gharbi

Modification of pomological characteristics and flavour components of fruits and virgin olive oil following wastewater irrigation and soil tillage: Effects of agronomic practices on fruit and oil quality

BACKGROUND The experiment was carried out on olive trees cv. Chemlali, during two successive years (2013/2014). Two irrigation treatments (IT: Trees irrigated with wastewater; TRC: Trees grown under rainfed condition) were combined with two tillage practices (TTS: Trees grown in tilled soil; TNTS: Trees grown in non-tilled soil). RESULTS The results of the study showed that wastewater irrigation combined with soil tillage improved the pomological characteristics of olive fruits. The tree yield increase was substantial for IT and TTS. However, most of the identified phenolic compounds, especially oleuropein, mainly accumulated in olive fruits of the TC block (TNTS + TRC), suggesting a marked improvement in the nutritional value of these fruits. Moreover, fruits of TNTS had high contents of sugar compounds, required for the synthesis of the fruit storage material. The study also showed that the agronomic practices affected the amounts of some aromatic compounds responsible for the distinctive flavour notes of olive oil. CONCLUSION Agronomic practices may affect considerably the commercial and nutritional values and the sensorial quality of the commodities.