Green argan oil extraction from roasted and unroasted seeds by using various polarity solvents allowed by the EU legislation

摘要

Argan oil (AO) has traditionally been used for its dermatologic and hepatoprotective effects and for human nutrition. Traditionally, AO extraction is carried out by Moroccan women with the help of stone mill pressing. However, it is long and slow process that frequently is achieved at deficit hygiene conditions. In this research, unroasted seeds (US) and roasted seeds (RS) of argan tree have been extracted using different extraction systems: n-hexane, n-hexane:acetone (1:1, v/v), ethyl acetate, acetone, ethanol:water (96:4, v/v), and water. The main results are; Hexane: acetone extraction yielded the highest FA amounts, at 39.7 g FA/100 g of total US seed, followed by acetone (36.5 g FA/100 g US seed). The main FA in all extracts were oleic acid, from 52.1 (ethanol:water) to 57.7% (hexane), and linoleic acid from 22.9 (hexane, US) to 29.3% (ethanol:water, RS), both of total FA. Oxidation levels, computed by conjugated diene index (CD), was extremely low for all extraction processes. CD were higher in RS in comparison with US, due to compounds produced in Maillard reactions. Colour parameters indicated a color variation from yellow (US) to brown (RS). Therefore, the conclusions can be summarized as follows. All extracting systems yielded good quality argan oil, thus, the tested procedures constitute a suitable alternative to the traditional extraction processes. The obtained oils could be used in the alimentary and cosmetic industries with different applications. Future research should be directed to check the unsaponifiable fractions of the oils here obtained. Overall, this research opens new perspectives for industries focused on argan oil extraction. (C) 2020 Elsevier Ltd. All rights reserved.