Udjel ukupnih fenola i antioksidacijska svojstva sladovina pripravljenih od pilsner, münchenskog i karamelnog ječmenog slada

undergraduate thesis

• Title (english): Total phenol content and antioxidant properties of worts made by pilsner, munchen and caramel barley malt
• Author: Katja Cukon
• Mentor: Sunčica Beluhan (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology); Zagreb
• Defense date and country: 2012-06-29, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Fenolni spojevi iz ječma i ječmenog slada značajno utječu na proces proizvodnje piva, te organoleptička i reološka svojstva sladovine i piva. Ovisno o sorti ječma, ne mogu se zanemariti antioksidacijska svojstva ječmenog slada. Cilj ovog rada bio je usporediti udjel ukupnih fenolnih sastojaka i antioksidacijska svojstva tri različita tipa slada – Pilsner, münchenskog i karamenog. Sladovine su pripravljene infuzijskim postupkom (Kongresna metoda). Udjeli ukupnih fenola u ječmenim sladovima i sladovinama pripravljenim od njih mjereni su spektrofotometrijski prema Folin-Ciocalteu metodi i izraženi kao ekvivalenti galne kiseline (GAE). Svi su tipovi slada imali značajan udjel fenolnih spojeva (3,53-6,77 mg GAE/g s. tv.). Antioksidacijska aktivnost Kongresnih sladovina mjerena je određivanjem redukcijske snage koja se temelji na redukciji Fe3+/K3Fe(CN)6 kompleksa do Fe2+. Sve su sladovine bile dobar izvor antioksidanasa (1,25 – 2,25 g Trolox/ml uzorka).

Abstract (english)

Phenolic compounds presented in barley and barley malt significantly impacted brewing process, organoleptic and rheological properties of wort and beer. Depending of the barley variety, the antioxidant properties of barley malt are not negligible. The aim of current research was to compare the content of total phenolic compounds and antioxidant properties of three different malt types – Pilsner, Munich and Caramel. Worts were produced by the infusion method (Congress method). The total phenol content of barley malts and worts was determined by spectrophotometric assay according to Folin-Ciocalteu colorimetric method and expressed as gallic acid equivalents (GAE). All barley malt types exhibited significant content of phenolic compounds (3.53 - 6.77 mg GAE/g dry weight). The measurements of the antioxidant activity using reducing power based on the reduction of a Fe3+/K3Fe(CN)6 complex to Fe2+ were assessed in the Congress worts. All worts were found to be a good source of antioxidants (1.25 – 2.25 g of Trolox equiv/mL).

• Keywords: ječmeni slad; antioksidacijska svojstva; udjel ukupnih fenola; sladovina
• Keywords (english): barley malt; antioxidant properties; total phenol content; wort
• Language: croatian
• URN:NBN: urn:nbn:hr:159:212113
• Study programme: Title: Biotechnology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka biotehnologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-16 10:18:47