Antioksidacijska svojstva ekstrakata kave

undergraduate thesis

• Title (english): Antioxidant properties of coffee extracts
• Author: Marija Košta
• Mentor: Draženka Komes (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Chemistry and Technology of Carbohydrates and Confectionery Products); Zagreb
• Defense date and country: 2011-02-17, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Kava se ubraja među najpopularnije napitke koji se konzumiraju širom svijeta. Sadrži značajan udjel polifenola zbog čega ima izražena antioksidacijska svojstva. Ekstrakcija se provodi vrućom vodom, a dobiveni napitak se konzumira u toplom obliku. Kava sadrži različite bioaktivne spojeve među kojima su najpoznatiji alkaloid kafein te polifenolni spojevi (derivati klorogenske kiseline). Cilj ovog istraživanja bio je odrediti udjel polifenola u 12 različitih ekstrakata kave te odrediti njihov antioksidacijski kapacitet. Za određivanje udjela ukupnih fenola primjenjena je Folin-Ciacolteau metoda, dok je antioksidacijski kapacitet određen primjenom tri različite metode: ABTS (2,2'-azinobis(3-etilbenzotiazolin-6-sulfonska kiselina)), DPPH (2,2-difenil-1-pikrihidrazil) i FRAP (Ferric Reducing Antioxidant Power). Određeni udjel ukupnih fenola u ekstraktima kave kreće se između 1722 ± 0 i 3454,55 ± 181,82 mg GAE/L. Primjenom sve tri metode određivanja antioksidacijskog kapaciteta potvrđeno je da svi ispitivani ekstrakti kave imaju izražena antioksidacijska svojstva.

Abstract (english)

Coffee is counted among the most popular beverages consumed worldwide. It contains a considerable amount of polyphenol, which gives it clear antioxidant properties. The extraction is performed using hot water, and the resulting beverage is consumed while warm. Coffee contains various bioactive compounds. The most known are caffeine and polyphenols (chlorogenyc acid derivate). The aim of this research was to determine the proportion of polyphenol in 12 different coffee extracts and to determine their antioxidant capacity. To determine the proportion of total phenols, the Folin-Ciacolteau method was used, while the antioxidant capacity was determined using three different methods: ABTS (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid), DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (Ferric Reducing Antioxidant Power). Amount of determined phenols is between 1722 ± 0 and 3454,55 ± 181,82 mg GAE/L. Using all three methods for determining antioxidant capacity it is confirmed that all tested coffee extracts have clear antioxidant properties.

• Keywords: antioksidacijska svojstva; kava; polifenoli
• Keywords (english): antioxidant activity; coffee; polyphenols
• Language: croatian
• URN:NBN: urn:nbn:hr:159:267164
• Study programme: Title: Food Technology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka prehrambene tehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka prehrambene tehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-18 09:34:32