ESSENTIAL OILS FROM AROMATIC PLANTS (THYMUS BROUSSONETTI BOISS, ORIGANUM COMPACTUM BENTH, AND CITRUS LEMON (L) N.L BURN.)  AS NATURAL ANTIOXIDANTS FOR OLIVE OIL

Malika  CHARAI   M. FAID  A. CHAOUCH  

ABSTRACT

Essential oils obtained by steam distillation from Moroccan oregano (Origanum compactum, lemon (Citrus limon) and Moroccan thyme (Thymus broussonetti) were analyzed for their chemical composition by gas chromatography. These EO were then used  in two concentrations (0.05 % and 0.1 %) in refined olive oil in 6 trials and a control to study the antioxidant properties. The antioxidant activity of the oils was followed up by the determination of the peroxide value and the acid value of the oil over a period of  6 months. Sensory evaluations of the trials were also conducted by a taste panel of 6 assessors for an organoleptic assessments. Results showed a wide variation in the antioxidant activity of the three oils, and also a slight variation between the two concentrations was observed. The highest activity was observed with thyme oil followed by oregano oil, while an organoleptic quality improvement was obtained with the oregano and lemon oils.