Kinetic Spectrophotometric Method for the Determination of Trace Formaldehyde in Food Products

A spectrophotometric method was developed to measure trace formaldehyde based on the inhibition effect of formaldehyde on the oxidation of alkaline magenta by potassium bromate in sulfuric acid medium. The experimental conditions including the reagent concentration,the reaction temperature and time were optimized at fixed reaction time.The linear range of the determination for formaldehyde is 0.08~1.0 mg·L-1,and the detection limit is 0.015 mg·L-1.The method has been used to determine the formaldehyde content in the water-floated food and the recoveries between 93% and 105% are obtained.