Pollock liver oil extraction using a new enzyme obtained from the Aspergillus oryzae strain

Abstract

A distinctive feature of fish fats from fats of plants and terrestrial animals is the presence in their composition of highly unsaturated and polyunsaturated omega-3 fatty acids (eicosapentaenoic and docosahexaenoic acids), which causes their high biological value. A typical type of raw material for obtaining edible fat is cod liver, which makes up about 10% of the weight of fish and contains an average of about 50% lipids. The Far Eastern pollock liver with a high content of polyunsaturated fatty acids has similar characteristics. From a technological point of view, the complexity of extracting these biologically valuable components is due to the high sensitivity of fish oil lipids to oxidation. The article discusses the use of new enzyme Protorizin-LAP obtained at Russian scientific research institute of food biotechnology using Aspergillus oryzae strain - a producer of a complex of exo- and endopeptidases with an increased activity of leucine aminopeptidase. Oil yield (%) and acid value (mg KOH/g oil) are considered as efficiency criteria for enzymatic hydrolysis. Optimization results of enzymatic hydrolysis of the pollock liver using a full-factorial experiment for two factors are presented. The optimal values of the factors are established: the dosage of the enzyme preparation Protorizin-LAP (0.4% by weight of the raw material) and the duration of the enzymatic hydrolysis process (1 hour). The study of the comparative enzymatic analysis of pollock liver showed that the use of the enzyme preparation "Protorizin LAP" in the technological process of processing fat-containing fish. The laboratory sample is not inferior to commercial analogues in terms of the ability to extract fat from pollock liver and may be promising in the processing of other raw materials of animal origin.