Effect of storage on oxidation stability of essential oils derived from culinary herbs and spices

摘要

Oxidation stability of essential oils isolated from different herbs and spices was observed during 10 weeks at 10 degrees C. The progression in hydroperoxides which was exhibited by the increase in peroxide values (p 0.05) was observed in all essential oils with the increase in shelf life. Amongst all tested essential oils, EC showed the highest preventive capacity against lipid oxidation. Similarly, elevated levels of thiobarbituric acid reactive substances and p-anisidine of essential oils were observed when shelf duration progressed (p 0.05). The essential oil of EC also showed the highest antioxidative potential during the study and a negative correlation with the lipid oxidation studies was observed. As lipid-based foods are vulnerable to oxidation which leaves them off-odour and simultaneously decrease in nutritional attributes. Therefore, the application of natural antioxidants such as essential oils can be a potent substitute to reduce the rate of lipid oxidation and rancidity of food items during prolonged shelf life. Prior to addition of these antioxidant rich essential oils, it is necessary to assess the oxidation behavior of these essences to determine their antiperoxidative mechanism when incorporated in food matrices.