Improving oxidative stability of flaxseed oil with a mixture of antioxidants

Abstract

The optimum combination of antioxidants used for stabilization of flaxseed oil and extension of its shelf life was examined. To achieve this goal, based on different antioxidant mechanisms, a combination of four types of antioxidants including tocopherol, ascorbyl palmitate (AP), phytic acid (PA), and a source of polyphenol (antioxidant of bamboo leaves (AOB), rosemary extract (RE), tea polyphenols extract (TP), and tea polyphenol palmitate (TPP)) were added to flaxseed oil. The effects were monitored using peroxide value (POV), thiobarbituric acid‐reactive substances (TBARS), free radicals, and Rancimat induction time (RIT) of flaxseed oil during accelerated storage. Flaxseed oil containing 80 mg/kg tocopherol, 40 mg/kg AP, 40 mg/kg PA, and 240 mg/kg TPP was found to be more stable to oxidation than other samples and had 3.22‐fold longer shelf life than that of the control flaxseed oil. PRACTICAL APPLICATIONS: Due to its high concentration of alpha‐linolenic acid, flaxseed oil is prone to oxidation. To improve the oxidative stability of flaxseed oil and prolonging its shelf life, the optimum formulation and ratio of mixtures of antioxidants with different antioxidant mechanisms were studied. Our results indicated that the flaxseed oil containing 80 mg/kg tocopherol, 40 mg/kg AP, 40 mg/kg PA, and 240 mg/kg TPP was very stable to oxidation. And the shelf life of the flaxseed oil containing this optimum mixture of antioxidants was 3.22‐fold longer than that of the control flaxseed oil. Therefore, adding the optimum mixture of antioxidants will help to produce the flaxseed oil products with better oxidative stability for commercial development.