IMPROVEMENT AND VALIDATION OF A METHOD FOR DETERMINING LOW-MOLECULAR-WEIGHT PHENOLS IN GRAPE SKINS

摘要

The aim of this study was to optimise and validate a method for analysing eleven phenolic compounds belonging to different subclasses (phenolic acids, stilbenes and flavonoids) in grape skins. The method proposed includes a solid phase extraction stepof purification and concentration prior to HPLC analysis. Under the optimised conditions, the total HPLC run time was reduced from 150 to 75 min. The method showed high precision (3-12%). There was a high linearity of response for all the compounds analysed (r~2>0.998) over the normal range for grape. The method was used to analyse the pheno-lics in Aglianico and Uva di Troia grape skins. Greater amounts of all the flavo-noids and stllbenes were found in the Uva di Troia grape skins with respect to theAglianico ones.