Simple Method for Determining Peroxide in Edible Oils and Dressing. II

: The modified ferric thiocyanate method previously pubulished by the author was evaluated for use in the determination of peroxide (PV) in emulsified liquids such as dressings without oil extraction. The values obtained by this method showed close agreement with PV (JOCS acetic acid-isooctane method) of oils extracted from dressings and edible oils used in the preparation of dressings. The method was found applicable to the simple determination of PV for very small samples, food emulsions, edible oils and fatty acids. The solvent of this method (ethanol: 1-butanol=6:4 vol/vol) may be reused by distillation under reduced presspre followed by additional distillation at atmospheric pressure. Samples and reagents for PV measurement are required in lesser amounts, and solvent retrieval is possible. These features show the method to be environmentally friendly.