PROBLEM TO BE SOLVED: To provide a method for efficiently producing an oxo fatty acid-containing composition in a short time. A method for producing an oxo fatty acid or an oxo fatty acid-containing composition, which comprises allowing a fatty acid to act on lipoxygenase in the presence of a reducing agent and a reduced dissolved oxygen concentration. [Selection diagram] None【課題】オキソ脂肪酸含有組成物を短時間で効率よく製造する方法等提供すること。【解決手段】還元剤の存在下、及び、溶存酸素濃度低減下で、脂肪酸にリポキシゲナーゼを作用させることを含む、オキソ脂肪酸又はオキソ脂肪酸含有組成物の製造方法等。【選択図】なし
