Metal content and physicochemical parameters used as quality criteria in virgin argan oil:: Influence of the extraction method

Metal content was determined in 26 samples of virgin argan oil from Morocco. An ETA-AAS with previous sample dilution with MIBK technique was used. In oil obtained by traditional method, Fe ranged from 0.8 to 4.0 mg/kg, Cu from 160.4 to 695.7 mu g/kg, Cr from 10.3 to 55.3 mu g/kg, Mn from 18.1 to 70.8 mu g/kg, and Pb from 28.5 to 450.0 mu g/kg. In oil obtained by a half-industrialized method, Fe ranged from 0.8 to 1.7 mg/kg, Cu from 158.4 to 385.0 mu g/kg, Cr from 10.0 to 48.1 mu g/kg, Mn from 15.0 to 68.5 mu g/kg, and Pb from 32.0 to 100.0 mu g/kg. Acidity value, peroxide index, K-270 and K-232, humidity and sludge volatile, and insoluble sludges in petroleum ether were also determined. A high variability in these quality parameters and a decrease of the quality in the oils obtained by the traditional method were observed.