3.3 Fatty acid compositions
As
shown in Table 2, fourteen major fatty acid components were detected and
identified, including eight saturated fatty acids, four monounsaturated
fatty acids and two polyunsaturated fatty
acids.
Comparing
the composition of AEEO and SEO fatty acids, it was found that there
were some differences presented in fatty acid contents, while no obvious
difference in their types was
detected.
The
results showed that the extraction method had no significant effect on
fatty acid composition of oils, which was in agreement with other
reports (Jiao et al., 2014; Li et al., 2013).
The
contents of fatty acid obtained were different from the values obtained
by Trevisani Juchen et al. (2019). The difference in fatty acid contents
might be attributed to the cultivars, planting regions, climate
conditions, and the posttreatment process (Liu et al., 2019).
It could be observed that the preponderant fatty acid in RBO was
linoleic
acid (38.26%-38.84%), oleic acid (33.83%-34.31%), followed by
palmitic acid (19.17%-19.87%). It also could be seen that the content
of unsaturated fatty acids accounting for about 75% of total fatty
acids in AEEO and SEO. Moreover,
the contents of monounsaturated fatty acids and
polyunsaturated
fatty acids in AEEO were much higher than that of
SEO.
It was likely because the relatively mild extraction conditions of AEE
was not easy to cause the oxidation and decomposition of unsaturated
fatty
acids.
According
to the literature, the oil contains a high level of monounsaturated
fatty acid, which has a great potential to produce biodiesel (Lovato,
Pelegrini, Rodrigues, Braz De Oliveira & Piloto Ferreira,
2014).
The
high proportion of linoleic and linolenic acids were precursors of
polyunsaturated fatty acids from the omega-3 and omega-6 series and were
essential for human health and disease prevention, which indicated their
potential development prospects in health products and pharmaceutical
industries (Chen, Luo, Qi & Wan, 2014), but also reduced oil stability
and shelf life (Haiyan, Bedgood, Bishop, Prenzler & Robards,
2007).
Therefore, compared with SE, AEE can reduce costs and green production,
while AEEO also has health benefits.