Practical Methods for Lipid Peroxides Determination

Lipid oxidation is a major problem in quality control of oil and fat, oil-containing products, and even in lipid metabolism. Unsaturated lipids form hydroperoxides as the major primary products in their early autoxidation process, followed by producing many kinds of decomposed and polymerized products as the secondary products. Therefore, many determination methods, such as peroxide value method for hydroperoxides, carbonyl value method for carbonyl compounds, acid value for free fatty acid, and various instrumental analyses such as HPLC, GC, some spectrometries etc., have been proposed to evaluate the oxidation degree of lipids. In the determination of lipid peroxides, it is an essential to understand the characteristics of the individual method and then to select the suitable method in accordance with the purpose of measurement and the properties of lipid sample. In the present paper, we will describe some practical determination methods for lipid peroxides, especially in focusing on peroxide value methods including a novel potentiometric titration method for the lipid hydroperoxides determination, which has excellent precision and reproducibility.