DETERMINATION OF COPPER AND IRON IN MUST - COMPARISON OF WET AND DRY ASHING

The concentration of copper and iron was determined in Spanish musts o btained at different pressures from three grape varieties: Macabeo, Xa rel.lo, and Parellada (which are used in the production of white wine) . Two types of organic matter destruction (dry and wet ashing) were te sted. Precision and recovery data for both metals were obtained by ato mic absorption spectrophotometry. The procedures were not statisticall y different for the copper analysis, but wet ashing produced low recov ery values for iron. Both metals were easily separated with the first must coming out of the press, not being dependent on the pressure exer ted on the grapes.