Sensory and some chemical characteristics of olive oils produced in Libya

Abstract

Libya is one of the considerable olive oil producers in North Africa. The consumption of olive oil in this country is part of the cultural heritage and a large number of individual manufacturers produce oil applying the process of cold pressing. The aim of this work was to determine the sensory profile and some main chemical characteristics, as free fatty acids, peroxide value, total phenols content and induction period of virgin olive oils. Oil samples were extracted from a blend of three olive cultivars typical for Libya: Roghiani, Hammudi and Endori, harvested in five different regions of northern Libya in the crop year 2015. Obtained results have shown that investigated olive oil samples were characterized by different sensory profile and chemical characteristics, due to peculiar effect of harvest areas of olive fruit. On the basis of investigated attributes, some oils were of excellent quality, but other were under. The free fatty acid contents varied between 0.73% to 2.78 % of oleic acid, peroxide values ranged from 6.40 mml/kg to 13.65 mmol/kg and induction period from 4.89 h to 18.33 h. The content of total phenols, as especially important compound for health benefit of olive oil, was also significantly various, from 56.0 to 238.3 mg GAE/kg of oil. It can be concluded that the oil from Gharyan production region was quite different from the other Libyans’ olive oils. This oil had the best sensory profile, basic chemical quality, oxidative stability and the highest phenolic content.

Keywords

• olive oil
• sensory quality
• acidity
• peroxide value
• oxidative stability