SULFITE DETERMINATION IN JUICES USING HPL C-ENZYME-REACTOR-COUPLING

The influence of sample preparation on sulfite determination in juices using HPLC-enzyme-reactor-coupling has been checked and improved. Bec ause grape juice might be sulfurized during production this was primar ily studied. In contrast to the reference-method ''IFU 7a'' the HPLC m ethod can prove whether the juice has been treated with SO2 or not. Th is is important because of the higher quality and price of unsulfurize d HTST-juices. The declaration ''unsulfurized'' can now be checked def initely, an important fact for allergicans, too. This method can espec ially determine stable bound sulfite compounds in desulfurized product s, e.g. grape juice. The advantages of this method are rapid and easy sample preparation (without destillation), the possibility of automati on, low costs and use for serial analysis. As it provides the more exa ct results the introduction as a reference method should be considered .