Pholyphenolic compounds and antioxidant activity of Chardonnay and Malvazija istarska

U radu je ispitivan utjecaj prinosa grožđa na polifenolni sastav i antioksidacijsku aktivnost bijelog vina sorte Chardonnay i Malvazije istarske. Za određivanje antioksidacijske aktivnosti vina primijenjene su DPPH, FRAP i ABTS metode. Ukupni polifenolni spojevi određeni su metodom sa Folin-Ciocalteovim reagensom. Identifikacija i kvantifikacija pojedinačnih polifenolnih spojeva određena je metodom tekućinske kromatografije visoke djelotvornosti. Utvrđeno je da prinos grožđa utječe na udjel polifenolnih spojeva vina. Najzastupljeniji polifenolni spoj u vinu je trans-kaftarinska kiselina. Promatrana je i korelacija između udjela ukupnih polifenolnih spojeva vina i antioksidacijske aktivnosti. Između udjela ukupnih polifenolnih spojeva i antioksidacijske aktivnosti određene DPPH i ABTS metodom postoji korelacija, dok između udjela ukupnih polifenolnih spojeva i antioksidacijske aktivnosti određene FRAP metodom nema značajne korelacije.The subject of this seminar is examination of the influence of grapes on polyphenolic and antioxidant activity regarding the white wines of sort Chardonnay and Malvazija istarska. For determination of antioxidant activity the following methods were used: DPPH, FRAP and ABTS method. The total of polyphenolic compounds was determined by using a method that utilizes the Folin-Ciocalteov reagent. Identification and quantification of individual polyphenolic compounds was determined by utilizing the HPLC method. It was determined that the yield of the grapes influences the yield of polyphenolic compounds in wine. The most common polyphenolic compound was determined to be the trans-caftaric acid. The correlation between the total yield of polyphenolic compounds in wine and antioxidant activity was also observed. Between the total yield of polyphenolic compounds and antioxidant activity, determined by DPPH and ABTS method, a correlation was determined, while when FRAP method was utilized, no significant correlation was found