Agronomic and Technological Factors Affecting Tunisian Olive Oil Quality

Ines Gharbi,Mohammed Hammami,Imed Cheraief,Sounira Mehri,Manel Issaoui,Samira Sifi

doi:10.4236/as.2015.65051

Abstract

Olive oil is a very versatile product. It has distinctive virtues in the fields of health and nutrition. For this reason olive oil quality has attracted attention and become the focus of many studies. Olive oil quality depends on several factors such as ripening, extraction method, soil type, climatic conditions, harvesting time, varieties and storage conditions. Quality assessment of olive oil is linked to an important series of physicochemical parameters including free fatty acid content, peroxide value and sensory evaluation. The main objective of this study is to investigate using statistical analysis, the main factors influencing the quality of Tunisian olive oils. Physicochemical analysis of 89 samples of olive oil produced in the region of the Sahel and central Tunisia. This study demonstrates that the main factors influencing Tunisian olive oil quality are: olive ripening, harvesting methods, olive pre-processing storage, olive washing, leaf removing, mixing, separation systems and crushing time. The data also shows that the commercial qualitative parameters of virgin olive oil such as free fatty acids, peroxide value, specific spectrophotometric absorptions in the UV region and sensorial assessment depend on the cultivar and quality of olives before processing. The application of good olive-growing practices complemented by studies similar to this would improve the quality of olive oil produced in Tunisia. This will contribute to the promotion and value of these oils as a regional product.

Highlights

Virgin olive oil (VOO) is a foodstuff extracted from the fruit of Olea europea L. and, it is a valuable product majority produced in the Mediterranean basin
Important chemical changes occur inside the drupe [4] and may affect the quality of the olive oil [10] [11]
We have found that the free acidity, the rate of polyunsaturated fatty acid synthesis and the sensory evaluation are affected by the ripeness of the pressed olives

Summary

Introduction

Virgin olive oil (VOO) is a foodstuff extracted from the fruit of Olea europea L. and, it is a valuable product majority produced in the Mediterranean basin. Olive oil plays an important role in the Tunisian agronomy and economy. Mechanical methods are used to extract the olive oil in order to preserve its characteristic properties responsible for its nutritional, health benefits and pleasant flavor. The quantity of FFA is an important factor for classifying olive oil into commercial grades [4] [5]. Some parameters that are not included in the IOOC and EC standards [2] [3], such as phenolic content, are known to have a significant effect on the stability and sensory characteristics of olive oil

Objectives

Results

Conclusion