In chocolate milk there is a dissacharide as in any other milk called lactose (milk sugar), which is composed of glucose and galactose. However lactose is non-reducing sugar, therefore if carrying on Benedict`s test, you have to break non-reducing sugars ( disaccharides) into their monosaccharide form, so they can react with Benedict`s reagent. First you will have to heat milk with an acid to hydrolyse any glycosidic bonds present. This will release free monosaccharides. Benedict`s need alkaline conditions to work so you need to neutralise the milk by adding of alkali sach as NaOH and then add Benedict`s reagent and heat as if carrying test for reducing sugars. Solution will go red.
