Journal of Environmental Treatment Techniques
2020, Volume 8, Issue 3, Pages: 1075-1080
J. Environ. Treat. Tech.
Journal web link: http://www.jett.dormaj.com
Study of the Chemical Composition of Olive Oil
According to Its Mode of Extraction and Its Age
from the Olive Tree
Miloudi Hilali *, Nadia Maata , Hanae El Monfalouti and Badr Eddine Kartah
Laboratory of Plant Chemistry and Organic and Bioorganic Synthesis, Faculty of Science, University Mohamed-V, Av. Ibn Battouta, BP 1014 Agdal-
Official Laboratory for Chemical Analysis and Research 25, Rue Nichakra Rahal, Casablanca, Morocco
A comparative study of the chemical composition of olive oil was carried out in the Massmouda district of Ouezzane, a city in
northern Morocco. It was made in order to study the influence of the extraction temperature and the age of the olive tree on the
chemical composition of olive oil. To carry out this work, we selected four samples of olive oil of the same kind (Moroccan
Picholine), from the same place and extracted at different temperatures, but these samples were collected from olive trees of different
ages. For this we performed physico-chemical analyzes such as acidity, peroxide index, absorbance in ultraviolet, fatty acids, sterols
and triglycerides. The result of this work shows that the temperature of olive oil extraction can increase the peroxide index, acidity, the
percentage of oleic fatty acid (C18: 1), the percentage of stigmasterol, and the percentages of triglycerides OOO, POO and can
decrease the percentage of fatty acid such as: C18: 0, C18: 2 (vitamin F) and the percentages of triglycerides LLL, LOL, OLO, PLO.
The results of the chemical composition according to the age of the olive tree reveal that the percentages of oleic acid (C18: 1), the
percentages of the triglycerides LLL, OOO are decreased with the increase in the age of the olive tree. On the other hand, our study
demonstrates that the percentage of linoleic acid C18: 2 (vitamin F) is increased with the increase of the age of the tree. In the end our
study proved the high quality of olive oil extracted by cold mechanical pressing.
Keywords: Olive, Fatty acids, Sterols, Triglycerides, Extraction temperature, Olive age
Olive oil is practically the only vegetable oil that can be
consumed in its raw form without prior treatment.
Appreciated for its flavor and nutritional characteristics, it is
known for its multiple virtues in the prevention of diabetes,
high blood pressure , certain cancers and aging . It is
also used in the pharmaceutical and cosmetic fields .
Making the pillar of the Mediterranean diet, several studies
have been carried out, on the fruit and leaves, to confirm the
ancestral virtues attributed to it [7-9]. This study is part of the
continuity of the research series performed by The Laboratory
of Plant Chemistry, Organic and Bio-organic Synthesis on
vegetable oils. To enhance olive oil and improve its nutritional
effect we followed some steps: (a) the study of the chemical
composition of olive oil according to the age of the olive tree;
The olive tree is a Mediterranean fruit tree that belongs to
the Oleaceae family. This tree produces olives; a fruit
consumed in various forms and from which olive oil is
extracted. In Morocco, the main cultivated fruit species is the
olive of the popular variety "Moroccan Picholine"  which
occupies an area of 560,000 ha. Olive groves contribute to
employment in rural areas with 11 million working days
annually. Olive production reaches the approximate figure of
60,000 T, generates 50,000 T of olive oils and 90,000 T of
industrial table olives . The olive tree develops in four
and flowering. The olive tree settles, expands but produces
Period of youth (1-7 years): it is the period of growth, size
b) the study of the chemical composition of olive oil
according to its mode of extraction and (c) to accomplish this
work, 4 olive samples belonging to the same region of
Morocco (the town of Ouezzane Douar Ghnioua) and of the
same variety "Moroccan Picholine" were selected.
Period of entry into production (7-35 years): it is in a way
the adolescence period of the tree which prepares for the
establishment of regular and significant productions.
Adult period (35-100 years): full production period (yield of
5 to 25 kg of olives per tree). The olive tree is in the prime of
2 Materials and methods
2.1 Presentation of the study area
Period of senescence (beyond 150 years): end of the tree's
productive life, little by little it produces less. Carpenter
branches die, trunk bursts.
The study region is the city of Ouezzane which belongs to
the southern margins of the Jebala area whose major tribes
bordering the city are: Masmouda, Rhouna, Ghzaoua and Beni
Mesara. The Ouezzane region, in the North of Morocco,
extends over an area of 1861.2 km², and has an altitude of 614
meters  (figure 1).
Corresponding author: Miloudi Hilali, Laboratory of Plant
Chemistry and Organic and Bioorganic Synthesis, Faculty of
Science, University Mohamed-V, Av. Ibn Battouta, BP 1014
Agdal-Rabat, Morocco. Email address: firstname.lastname@example.org.