Description
(Recommended by Codex as type II method) The method has been tested on juice, jam, margarine, fish, cured meats, wine, bread, mayonnaise and pickles. The reliability of the method was studied in a method-performance study in which 11 laboratories participated. The preservatives are extracted from the food with a mixture of methanol and water. After filtration and isocratic reversed phase liquid chromatographic separation on a C-18 column, the preservatives are detected by means of a UV detector at 235 nm. Two different mobile phases are used, one for the separation of the free acids and one for the p-hydroxybenzoic acid esters. For the five preservatives the detection limit of the met¬hod is 5 mg/kg or lower.