Flaxseed oil containing essential fatty acids is cheap, plenty and highly used as edible oil in India, Asia and also in the western world but the oil is prone to oxidation. But with the incorporation of a new natural antioxidant (soluble ajowan (Carum copticum) extract), the oxidation of oil could be prevented. The oxidation properties of antioxidant in oil were compared with other synthetic antioxidants (TBHQ, BHT, EQ) at different temperatures. It has been observed that TBHQ showed higher thermal stability than other antioxidants but with comparison to cost with ajowan and for use as a spice in food preparations the above natural antioxidant is more preferred. (c) 2005 Elsevier Ltd. All rights reserved.