Determination of the Quality and Purity Characteristics of Olive Oils
Obtained from Olives Cultivated in Different Regions of Turkey,
Depending on Climatic Conditions
Abstract
Virgin olive oils (VOO) obtained from olives grown in different regions
of our country, under changing climatic conditions, show different
sensory and chemical properties. Due to the fact that primary production
is affected by climatic and agricultural conditions and VOOs are
supplied to the market by only physical processing. In order to
determine whether these deviations are due to climatic conditions, VOOs
were obtained from the olive samples collected from 39 orchards in four
Region where VOO production is intense in Turkey. Analyzes were carried
out regarding the quality and purity criteria of the VOOs. Samples were
collected in 2017/18-2020/21 harvest years (-2 on-2 off). The maturity
index (MI) values of olives and free fatty acidity (FFA), fatty acid
ethyl esters (FAEE), delta-7-stigmastenol values of olive oils ranged
between 0.94-4.15 and 0.07-1.27 (in oleic acid %), 1.56-27.32 mg/kg,
0.16-1.14%, respectively. Delta-7-stigmastenol values in 21 samples
were outside the limit specified in the legislation (0.50-1.14%). The
Fatty acid methyl esters (FAME) and FAEE of all olive oil samples were
within the specified limits. In the study, multiple regression analysis
was performed to investigate whether there is a relationship between
climate data and delta-7-stigmastenol values by years. According to this
result, it has been determined that the delta-7-stigmastenol value is
high when the annual average relative humidity is low and the annual
average temperature is high. There is an urgent need to make
forward-looking plans due to climate change.