Determination of oxidation degree of fish oils by thiobarbituric acid method with alkaline hydrolysis

Abstract

Determination of oxidation degree of fish oils by thiobarbituric acid method with alkaline hydrolysis T. WITASOptimum conditions were investigated that are required for the determination of lipids oxidation degree in fish oils by the thiobarbituric acid method using alkaline hydrolysis. The method, employing alkaline hydrolysis, was used t o determine the degree of lipids oxydation in selected fish oils and fish meals during production process and storage. Reagents and apparatusz-Thiobarbituric acid, pure (Fluka) ; sodium hydroxide, analytical reagent-grade, solution 0.35 N and 4 N ; sodium chloride, analytical reagent-grade; hydrochloric acid, analytical reagent-grade, solution 0.35 N and 4 N ; pH-meter LBS-65 ; Glass assembly with indirect steam distillation (Fig. I).PULPRICH photometer with filter S 53 (530 nm) ; Measurements and discussion of resultsExperiments were conducted on fish oils according t6 earlier determined method [zo] in successive procedure phases : alkaline hydrolysis of sample, acidification of 10.