AbstractThe corrosion of copper in lactic acid containing various colourants and sweetening agents has been studied. In plain lactic acid the corrosion increases with acid concentration up to 0.5 M and then decreases, but it increases continuously with the time of immersion and temperature. Pure buffalo milk (pH 6.45) and curd (pH 3.70) have almost no effect on copper. Addition of food dyes to lactic acid increases corrosion, the order of corrosivity being: amaranth