3.2.1 Fatty acid profiles
The fatty acids of Coratina and Koroneiki in different age are presented
in Table 2, and they are all in agreement with the EVOO standard. On the
other side, there were significant differences between Coratina and
Koroneiki in fatty acids, mainly in oleic acid, linoleic acid and
stearic acid. Owing to the differences in the content of oleic acid and
stearic acid, there was a gulf existing in the ratio of MUFA to PUFA
(MUFA/PUFA) of Coratina and Koroneiki. Contents of other fatty acids
were similar, so the ratio of UFA to SFA (UFA/SFA) was little difference
in all the samples. Significant differences were also found in the same
variety of different ages. As can be seen in Table 2, the percentages of
major fatty acids in Coratina and Koroneiki oils varied irregularly
according to tree age. The capricious fluctuation in fatty acid resulted
in MUFA/PUFA and UFA/SFA in Coratina and Koroneiki oils showed a jumble
variation with tree age.
There are plenty literature reports focusing on the effects of varieties
on fatty acid profiles. In addition, previous reports have been
demonstrated that geographical condition greatly affects the fatty acids
of olive oils from the same cultivar. Compared with the Coratina oils
around the world, the mean percentage of palmitic acid was in a high
level, oleic acid was in a low level, and linoleic acid was in an
intermediate level in Coratina oils in the present study (Aparicio &
Luna, 2002; Bruscatto et al., 2017; Ceci, Mattar, & Carelli, 2017;
Fuentes et al., 2018). Koroneiki was another widely planted olive
variety in the world. In comparison with the Koroneiki oils from other
regions, the mean percentage of palmitic acid was in a high level, oleic
acid was an intermediate level, and linoleic acid was in a low level in
the studied Koroneiki oils (Fuentes et al., 2018; Wang et al., 2018).
Besides, the effects of tree age on fatty acid profiles were not exactly
the same as the existing reports. Chtourou et al. have been concerned
about the effects of olive trees age on fatty acid composition and found
that the variations of fatty acid composition were not significant with
respect to tree age (Chtourou et al., 2017b). However, tree age existed
unclear effects on fatty acid compositions in this study.