Physicochemical Characteristics of Extra Virgin Olive Oils Obtained By Ultrasound Assisted Extraction from Different Olive Cultivars

Abstract

In this study, the influence of malaxation time combined by ultrasound on the extraction yield, oxidative and quality characteristics of Extra Virgin Olive Oils extracted from of Edremit, Gemlik and Uslu cultivars were studied. The extraction yield, free acidity, peroxide value, p-anisidin value, total oxidation value, K232 and K270, total phenol compound , the content of total chlorophyll and total carotenoid compounds were determined. Different sonication and malaxation time combinations did not induce difference (P˃0.05) in the Edremit oil yield and extractability indexes However, they were significantly different in Gemlik and Uslu oils. Oils obtained from olive pastes treated with 8 minute ultrasound improved Uslu oil yield 1.74% and the oil extractability 10.32%. Moreover, the amounts of chlorophylls and carotenoids were highest in samples subjected to 8 minutes sonication treatment whereas they were lowest in olive oils subjected to 12 minute ultrasound. Oils extracted by 8 minute sonication showed higher oxidative stability as proven by their lower FFA, p-AV, PV and TOTOX values than those extracted by 4 and 12 minute sonication. The total phenol content of EVOOs decreased as ultrasound time increased.

Keywords: Extra Virgin Olive Oil, Malaxation, Physicochemical Properties, Olive Cultivars, Ultrasound.