Optimization of the microwave treatment of linseed for cold-pressing linseed oil - Changes in its chemical and sensory qualities

Response surface methodology was applied to estimate the effects of two independent variables, microwave power and pre-treatment time, of linseed on the cold-pressed linseed oil parameters associated with health and sensory characteristics. Microwave-treated oils had lower amounts of secondary oxidation products (AnV = 0.97-1.47) and antioxidant activity (DPPH = 209.9-315.1 mu mol TE/100 g) than those of untreated oil (AnV = 1.37 and DPPH = 353.0 mu mol TE/100 g). However, these oils were a richer source of oleic acid and had a higher sensory scores for odour and flavour. The optimal conditions were predicted and the quadratic response surfaces were drawn from the mathematical models in order to ensure the best quality of linseed oils. The pre-treatment of linseed using microwave radiation is a promising technology that can improve the chemical and sensory properties of cold-pressed linseed oils.