Enzymatic hydrolysis of salmon oil by native lipases: optimization of process parameters

in an attempt to concentrate the content of n-3 polyunsaturated fatty acids (n-3 pufa) in the residual acylglycerol, salmon oil (n-3 pufa content of 30.1%) was hydrolyzed with three kinds of native microbial lipases (aspergillus niger, rhizopus javanicus and penicillium solitum). for each lipase, a response surface methodology was used to obtain maximum pufa content and to optimize the parameters of enzymatic reactions with respect to important reaction variables; temperature (x1), amount of lipases (x2) and water/oil ratio (x3). based on these results, optimal reaction conditions were established. aspergillus niger lipase was the most effective in concentrating n-3 pufa. the degree of hydrolysis (60%) led to an increase in the docosahexaenoic acid (dha) content from 14.4% in the original oil to 34.0% (2.4-fold enrichment) in the residual acylglycerol under optimum conditions: enzyme concentration of 500 u g-1 oil, reaction temperature of 45 oc and water/oil mass rate of 2:1 (m/m) after 24 h reaction.