Iron, copper and zinc in white sugar from Serbian sugar beet refineries

Small amounts of soluble and insoluble impurities such as iron, copper and zinc in refined white sugar determine the usefulness of sugar for various industrial applications. The content of iron, copper and zinc was evaluated in 166 white sugar samples from four Serbian beet sugar refineries during the campaign of 2003. The production of the chosen sugar factories is accounted for about 70% of the total national sugar origin and the taken samples were representative of their production. Wet digestion was applied and the content of studied microelements was determined by flame atomic absorption spectrometry. The mean content of iron, copper and zinc (0.37, 0.06 and 0.02 mg/kg, respectively) was low in all the white sugar samples from the Serbian sugar refineries, but statistically it was significantly different from the content of the investigated elements in the sugar samples from European sugar factories. The iron content was significantly higher in Serbian sugar, while the content of copper and zinc found in sugar from Serbian refineries were significantly lower than the ones from some European beet refineries. The origin of these impurities was discussed as far as known.