Changes in Chemical Composition and Olive Oil Quality of Turkish Variety 'Kilis yağlık' with Regard to Origin of Plantation

Abstract

'Kilis yağlık' is the most common variety cultivated in the South-east region of Turkey and represents around 52% of the growing area. During the last few years new cultivars have been introduced in South regions being mostly the cultivar "Gemlik" without evaluating their behaviours in this environment. Unfortunately, it is now understood that this cultivar with good plantation characteristics did not adapt well to the environmental conditions of South Turkey. This has led to an increase in the need of research on traditional autochthonous cultivars. 'Kilis yağlık' although shows alternate; has a high yield of fruits. The aim of this work is was to study changes in virgin olive oil composition of 'Kilis yağlık' variety according to origin of plantation. Olives from this variety were collected in four characteristic and representative olive growing locations in South-east of Turkey. The analytical parameters studied were fatty acid composition, total phenolics, chlorophylls and carotenoids, free acidity, peroxide value, colour indexes and some individual phenolic compounds. The contents of some of the individual phenolics (tyrosol, hydroxyl tyrosol, oleuropein, 4-hydroxyphenyl acetic acid, 3-4 hydroxy benzoic acid, taxifolin, verbascoside, vanillic acid, luteolin, apigenin and rutin) were determined with a qualitative and quantitative analysis performed by HPLC-DAD.