Ekstrakcija polifenola iz taloga vina sorte Žilavka pri povišenom tlaku potpomognuta mikrovalovima

master's thesis

• Title (english): Microwave-assisted extraction of polyphenols from wine precipitate varieties Zilavka under elevated pressure
• Author: Mateja Škunca
• Mentor: Marijana Jukić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Chemistry and Biochemistry); (Laboratory for Physical Chemistry and Corrosion); Zagreb
• Defense date and country: 2012-09-19, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

U ovom radu ispitan je utjecaj ekstrakcije potopomognute mikrovalovima na sastav i koncentraciju polifenolnih spojeva taloga vina sorte Žilavka. Ispitan je utjecaj vremena ekstrakcije pri povišenom tlaku (1,5 bar), vrste otapala te temperature i snage mikrovalova na efikasnost ekstrakcije. Korištena su tri otapala: destilirana voda, 50% vodena otopina etanola i 30% vodena otopina etanola. Koncentracija ukupnih fenolnih spojeva određena je FolinCiocalteu metodom, a pojedinačni fenolnih spojeva primjenom visokodjelotvorne tekućinske kromatografije uz UV- Photo Diode Array detekciju (HPLC UV/ PDA). Pokazalo se da ekstrakcijsko otapalo značajno utječe na koncentraciju ukupnih fenola (p<0,05). Najbolji ekstrakcijski kapacitet se postiže primjenom 50% vodene otopine etanola. Vrijeme i temperatura ekstrakcije nisu značajnije utjecali na izolaciju ukupnih fenola. HPLC UV/PDA analizom identificirano je 5 fenolnih kiselina: klorogenska, kafeinska, p-kumarinska, phidroksibenzojeva kiselina i galna kiselina.

Abstract (english)

In this paper the influence of microwave assisted extraction on the composition and concentration of polyphenolic compounds from wine precipitate varieties Žilavka from the winery Čitluk was investigated . The research was carried out so that the effects of the time extraction at encreased pressure (1.5 bar), solvent type, temperature and microwave power on the extraction efficiency were followed. The three solvents were used: distilled water, 50% aqueous solution of ethanol and 30% aqueous solution of ethanol. The concentration of total phenolic compounds was determined by Folin-Ciocalteu method, and individual phenolic compounds using high performance liquid chromatography with UV-photo diode array detection (HPLC / PDA). It has been shown that the extraction solvent significantly affects the concentration of total phenolics (p <0.05). The best extraction capacity is achieved by using 50% aqueous solution of ethanol. Time and extraction temperature did not significantly influence the extraction of total phenols. HPLC / PDA analysis identified five phenolic acids: chlorogenic, caffeic, p-coumaric, p-hydroxybenzoic acid and gallic acid.

• Keywords: Mikrovalna ekstrakcija; talog vina; polifenoli; zelena kemija; antioksidansi
• Keywords (english): Microwave extraction; wine precipitate; polyphenols; green chemistry; antioxidants
• Language: croatian
• URN:NBN: urn:nbn:hr:159:815646
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-09 09:31:42