DETERMINATION OF 12 ORGANIC-ACIDS AND 5-HYDROXYMETHYL FURFURAL IN FRUIT JUICES BY HPLC

A rapid and reliable HPLC method that allows the qualitative and quantitative determination of the most important acids occurring naturally or by exterior influence in fruit juices is presented. This method is advantageous in quality control as it brings about a time gain as compared to single enzymatic analyses. To obtain the best separation with the RP18 column Spherisorb ODS 2, various compositions of the liquid phase were tested. The use of the ion pair reagent tetrabutylammonium dihydrogenphosphate (TBAP) was decisive. Its concentration and the pH value influence the dissociation of the acids. This is essential for a good separation.