Development of a Sample Treatment Method for a Flow Injection Determination of Iodine in Eggs: A Comparison Study

A simple treatment method was proposed for the determination of iodine in eggs, followed by a flow-injection spectrophotometry based on the catalytic effect of iodine in the reduction reaction of Ce(IV) with As(III). The egg matrix was removed based on protein precipitation principles. Several protein precipitation methods were investigated. The treatment using trichloroacetic acid satisfactorily removed most of the egg matrix components. A colorless solution and a good signal were achieved. The method provided more reliable results compared to the conventional alkali dry ashing.