OXIDATION OF RAPESEED OIL - EFFECT OF METAL TRACES

Traces of heavy metals in edible oils are known to have an effect on the rate of oil oxidation. In this investigation we studied the effect of trace metals by excluding instead of adding them. Three supports were used to fix trace metals: grafted cellulose, cationic resin and absorbent resin. Cationic resin and grafted cellulose allowed copper (Cu) and iron (Fe) to be fixed. The measurement of peroxide value and variation of linolenic acid with temperature indicate good oxidative stability of oil processed on cellulose and cationic resin. These results confirm the effect of metals, particularly Fe and Cu, on oil oxidation.