Effect of fruits damaging during harvest time on extracted oil quality of Zard and Roughany olive cultivars

Fruits harvesting techniques are the most important factors that affected on olive oil quality. In this study, effect of fruit damage at harvest time on extracted oil quality of two olive cvs. Zard and Roughani were investigated. Fruits were harvested by hand and by rattan (the common method). Thereafter, hand harvested fruits were divided also into two subgroups, without damage (control) and artificial damage. Olive oil quality characteristics including free fatty acid (FFA), peroxide value (PV), coefficients K232, K270, total chlorophyll, total carotenoid, total phenol, total flavonoid, antioxidant capacity, IC50 and anti-raical efficiency (AE) were measured. Fruits damage during harvesting or artificially increased FFA and PV of both olive cvs. Zard and Roughani oil. In addition, a K232 and K270 coefficient of oil was more than control. Damaged fruits especially those harvested by rattan have showed less oil chlorophyll and carotenoid content than control. The highest amount of total phenol and total flavenoid content was observed in control fruits. Although, no significant differences were found among treatments. Overall, fruits damaging during harvest time and before oil extraction reduced some antioxidant compounds and increased FFA and PV, which resulted in declining olive oil quality, however no significant difference was found between damaged and intact fruits for oil antioxidant capacity.