Quality parameters of olive oils at different ripening periods as affected by olive fruit fly infestation and olive anthracnose

Abstract

Olive pests and diseases influence olive oil quality. Ayvalik olive cultivar is important between local cultivars grown in Turkey. This study aimed to monitor the effects of olive pests and diseases (olive fruit fly attack and olive anthracnose) on Ayvalik olive oil quality parameters such as free fatty acids (FFA), peroxide value (PV), specific extinction coefficients (K-232, K-270, and Delta K). Besides, Ayvalik olive fruits were collected at six harvest times, and the level of ripening with olive pests was also evaluated. Results showed that the FFA level influenced negatively by olive pests, mainly olive anthracnose. At the end of harvesting, FFA of oils from damaged olive anthracnose reached up to 5.42 (% oleic acid). Except for the first harvest period, the other quality parameters remained between limit values, and slight differences were observed between healthy and damaged olives. At the first harvest period, PV and K-232 (7.02 mEq O-2/kg, 2.22) of olive oil from fly-infected olive had higher values than the other samples. The stage of ripening, healthy, and damaged olives affected slightly certain fatty acids of the oils. Total phenolics, o-diphenol, and alpha-tocopherol content of oils from healthy fruits had higher values than oils from damaged olives. Besides, the antioxidant activity of oils obtained from healthy olives showed higher values compared to the oils from infected olive fruits.