Fenolne spojine in antioksidativni potencial v dolenjskih rdečih vinih

Kastelec, Lara (author), Košmerl, Tatjana (mentor), Abramovič, Helena (reviewer)

V diplomskem delu smo v prvi vrsti ugotavljali kako količina skupnih fenolov (SF) vpliva na antioksidativni potencial (AOP) vina. V šestih vzorcih vina, zvrsti modra frankinja, žametovka, zweigelt in cviček PTP, smo skozi trimesečno zorenje določali koncentracijo SF in AOP vina. Uporabili smo metodo za določanje fenolnih spojin v vinu po Singletonu in Rossiju, za določanje antioksidativnega potenciala pa metodo s prostim radikalom DPPH˙. Z metodo WineScan smo določili tudi kemijske parametre sestave vina in ugotavljali, kako se spreminjajo v času treh mesecev. Ugotovili smo, da z naraščajočo koncentracijo SF narašča tudi AOP vina. S časom smo tudi opazili, da so spremembe koncentracije SF in AOP sortno značilne za vino sorte žametovka. Koncentracija fenolnih snovi v večini vzorcev je skozi trimesečno zorenje nekoliko upadla. Koncentracija alkohola in vrednost pH se s časom ne spreminjata, medtem ko delež reducirajočih sladkorjev nekoliko upade. Opazimo tudi rahel porast hlapnih kislin, a so v večini vzorcev koncentracije zanemarljive, z izjemo vzorca 2, sorte modra frankinja, kjer je porast koncentracije hlapnih kislin nekoliko večji.

• Language: Slovenian
• Keywords: vino, rdeča vina, modra frankinja, žametovka, zweigelt, cviček PTP, antioksidanti, antioksidativni potencial, DPPH, fenolne spojine
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [L. Kastelec]
• Year: 2017
• PID: 20.500.12556/RUL-95623
• UDC: 663.25:547.56:577.1
• COBISS.SI-ID: 4835192
• Publication date in RUL: 21.09.2017

Secondary language

• Language: English
• Title: Phenolic compounds and antioxidant potential of red wines of Dolenjska

Abstract

In my graduation thesis we have been establishing how the concetracion of phenolic compounds is affecting the antioxidative potential of red wines of Dolenjska. We have been analysing six samples of four different wines such as Blue Frankish, Žametovka, Zweigelt and Cviček PTP. We have been using method of Singleton and Rossi for determing concentration of phenolic compounds and method for determing antioxidative potential by using DPPH˙ free radical. Finally we have used WineScan method to study how three months long maturing is affecting chemical properties of wine. We have established that by increasing of concentration of phenolic compounds so does increase antioxidative potential of wine, which is not only affected by concentration but also by characteristics of phenolic composition, what can be seen in case of samples of Žametovka. We have also observed that by three months of maturing the concentration of phenols is slightly decreasing. Concentration of alcohol and pH are not changing by time, while concentration of reduced sugars is decreasing. For most samples concentration of volatile acids is not changing or is slightly increasing, while sample 2 of Blue Frankish shows a bit higher values.

• Keywords: wine, red wines, Blue Frankish, Žametovka, Zweigelt, Cviček PTP, antioxidants, antioxidant potential, DPPH, phenolic compounds