Flaxseed oil stabilization using natural and synthetic antioxidants

Abstract

The aim of this work was to identify effective and safe antioxidants (AO) for stabilization of flaxseed oil and extension of its shelf life. A number of AO (both synthetic and natural ones) as well as their compositions are currently used for inhibiting oxidation processes. Their efficacy in flaxseed oil under conditions of accelerated oxidation at 100°С was tested. The fat‐soluble ascorbic acid esters displayed significant antioxidant activity. The stabilizing effect of ascorbyl palmitate (AP) was more apparent in the oil samples with higher alpha‐linolenic acid (ALA) content and lower oxidation resistance. AP alone ensured better stabilization efficacy than some known AP‐based compositions. Kinetic data were obtained characterizing accumulation of primary and secondary oxidation products in flaxseed oil added with AP during the storage at room temperature and with free access of the air. The calculated values of stabilization factor (3.7 and >6 at AP concentrations of 0.01 and 0.02%, respectively) demonstrated high inhibiting activity of AP under these conditions. It has also been found that haricot and soy beans, as well as compositions thereof, at an oil concentration of 0.8% effectively inhibit the oxidation and oxidative destruction of flaxseed oil lipids. Both AP and vegetable compositions based on legume seeds could be recommended for effective stabilization of flaxseed oil and substantial prolongation of its shelf life.Practical application: High antioxidant activity in flaxseed oil of fat‐soluble esters of ascorbic acid, as well as vegetable stabilizers based on haricot and soy beans, enables significant increase of the shelf life of the oil. The use of AP alone and legume based stabilizers ensure reliable and safe protection of flaxseed oil from oxidation, and these both methods are applicable to industrial production of edible flaxseed oil and the products on its basis. The corresponding technological methods of practical application of AP and vegetable legume‐based stabilizers in industrial production of oxidation‐resistant edible flaxseed oil have already been developed and introduced into oil production process by the authors of this article.Additive stabilizers based on bean and soybeans effectively inhibit the oxidation and oxidative destruction of flaxseed oil lipids. High antioxidant activity in flaxseed oil of vegetable stabilizers enables significant increase of the shelf life of the oil. The use of legume based stabilizers ensure reliable and safe protection of flaxseed oil from oxidation, and this method is applicable to industrial production of edible flaxseed oil and the products on its basis.