| 摘要 |
PURPOSE:To obtain the title treating agent preventing oxidation and deterioration of fats and oils without adding an antioxidant harmful to human body, comprising sodium sulfate containing a compounded ferrous and ferric iron salt. CONSTITUTION:For example, an aqueous solution of a water-soluble ferrous iron salt such as ferrous sulfate is added to a large amount of a solution of sodium hydroxide, ferrous ion is partially oxidized by a method of air introduction or forced stirring to give ferric ion and then excessive iron hydroxide or hydrated oxide are filtered off. The filtrate is neutralized with sulfuric acid, concentrated and evaporated to dryness, purified with a hydrous alcohol and dehydrated to the aimed sodium sulfate containing a compounded ferrous and ferric iron salt. |
