Enzyme-catalysed enrichment of n-3 polyunsaturated fatty acids of salmon oil: optimisation of reaction conditions

Extraction and concentration of polyunsaturated fatty acid from salmon oil(Salmo salar) by enzymatic hydrolysis were studied. Enzymatic aqueous extraction of oil with Neutrase (R) 0.51 was applied to the salmon flesh in batch reactor, Reaction kinetics were monitored under nitrogen by measuring the degree of hydrolysis (DH% using the pH-stat method, in order to preserve the functional and nutritional values of hydrolysates. lipids were separated by centrifugation yielding 14.3% (w/w) for the product, compared to 15.2% (w/w) obtained using the classical method with solvent. lipase hydrolysis by Novozym (R) SP 398, a specific sn-1, sn-3 enzyme, and membrane filtration, were evaluated as means of selectively concentrating polyunsaturated fatty acids (PUFA) fractions. A Doehlert matrix was used to study the effect of reaction time, flow and enzyme/protein ratio. Quadratic models were used to generate response surfaces of the liberation of fatty acids during the lipolysis and the composition of major saturated and polyunsaturated fatty acids in the permeate.