Process for removing polycyclic aomatic hydrocarbons from carnosic acid and its antioxidant

ObjectiveTo investigate the optimal technical conditions for the removal of polycyclic aromatic hydrocarbons (PAHs) in carnosic acid production.MethodsWith carnosic acid yield and PAHs residue as evaluation indexes, single factor test and orthogonal test were used to study the effects of activated carbon addition, extraction temperature and activated carbon operation time in the system on PAHs residue and carnosic acid yield. Antioxidants were added to oil and high temperature accelerated oxidation test was carried out, then the peroxide value index was measured to evaluate the anti-oxidation properties.ResultsThe optimal process for removing PAHs from carnosic acid with activated carbon was found that its addition ratio was 0.3%, extraction temperature was at 50 ℃ and operation time was 10 minutes. Under these conditions, a carnosic acid yield of 94.85% was achieved with residual PAHs at 43.12 μg/kg extraction storage period and at the same concentration, the anti-oxidation effects of the four antioxidants were TBHQ>carnosic acid>BHA>VE.ConclusionIt is feasible to remove PAHs from carnosic acid with using activated carbon while achieving a high yield of carnosic acid (CA) under specific conditions. In the long term, the anti-oxidation effect of 0.02% carnosic acid is equivalent to that of 0.02% TBHQ and the use of natural antioxidants is beneficial to human health.