Determination of some chemical and quality parameters of changes in turkish Sari Ulak monocultivar extra virgin olive oil during 12 months of storage

D Sivri Ozay,E Ghanbari Shend,M T Ozkaya,N F Ustunelc

doi:10.15673/fst.v12i3.1038

Abstract

In this study Turkish monocultivar extra virgin olive oil (EVOO) “Sarı Ulak” was extracted by using the Mobile Olive Oil Processing Unit (TEM Oliomio 500-2GV, Italy). Changes in minor and major components and quality characteristics, free fatty acid content, peroxide value and UV absorbance value, were surveyed during a year’s storage period. “Sarı Ulak” olive oil samples were classified as EVOO according to the trade standards of the International Olive Council (IOC) based on free fatty acid, peroxide value, K232 and ΔK values up to the eighth month of the storage period. The results have shown that color values of EVOO changed from green to yellow slowly while UV absorbance values changed during storing. Total polyphenol content of extra virgin olive oil decreased from 205.17 ppm to 144.29 ppm during a year’s storage. Luteolin was the most abundant phenolic compound, and its concentration changed from 184.33 ppm to 115.06 ppm. Apigenin concentration was differed from 2.67 to 1.06 ppm during storing. The initial level of α-tocopherol contents was 184.51 ppm, it decreased to 147 ppm at the end of storage time. After 12 months of storing, about 20 % of α-tocopherol content was destroyed. The amounts of phenolic and tocopherol isomers decreased during storage as expected.

Highlights

Formulation of the problemBesides fruit soundness, cultivar, agronomic conditions and harvesting techniques, extraction technology is another important factor that directly effects on olive oil quality
The results show that the tocopherol content (α, β, ɣ) decreased with increasing storage time as expected
There are some research works on the Sarı Ulak olive oils composition in scientific literature, the authors are not aware of a study about the effects of storage on Sarı Ulak olive oils. It has a very high potential for presentation as premium quality extra virgin olive oil (EVOO) in Turkey and in the international marketing due to high total phenols, tocopherol isomers, and high oxidative stability. This is the first report on the chemical composition, sensory properties, and the effects of storage of Sarı Ulak olive oil produced in the mobile olive oil processing unit

Summary

Introduction

Formulation of the problemBesides fruit soundness, cultivar, agronomic conditions and harvesting techniques, extraction technology is another important factor that directly effects on olive oil quality. Commercial virgin olive oil extracted from the Arbequina cultivar is reported to lose significantly chlorophyll, carotenoids, and total phenol contents of after 12 months of storage, but its oleic acid content increases [7]. Sarı Ulak was classified as extra virgin olive oil up to the seventh month of storing according to the results of free acid content, peroxide value (International Olive Council standards), K232 value.

Results

Conclusion