Utjecaj zagrijavanja na antioksidacijsku aktivnost bagremovog meda

master's thesis

• Title (english): Changes of antioxidant activity in acacia honey after heat treatment
• Author: Ena Lež
• Mentor: Ksenija Marković (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Quality Control); (Laboratory for Food Quality Control); Zagreb
• Defense date and country: 2013-02-28, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Tijekom ovog istraživanja analizirano je 30 uzoraka bagremovog meda (Varaždinska županija, sezona 2011), netretiranih, odnosno zagrijavanih 5 minuta pri 90 °C. Određen je udio ukupnih fenola modificiranom Folin-Ciocalteu metodom te antioksidacijska aktivnost pomoću dviju metoda, DPPH i FRAP. Prosječan udio ukupnih fenola u netretiranim uzorcima iznosio je 39,5±15,7, odnosno 37,1±15,4 mg GAE/kg meda u tretiranim uzorcima. Antioksidacijska aktivnost određena DPPH metodom u netretiranim uzorcima iznosila je 114,1±40,4, odnosno 155,2±64,7 mg mL-1 u tretiranim uzorcima. Antioksidacijska aktivnost određena FRAP metodom u netretiranim uzorcima iznosila je 42,3±5,3, odnosno 45,6±4,8 μM Fe(II) 10 %-tne otopine meda u tretiranim uzorcima. Istraživanjem je utvrđeno da zagrijavanje 5 minuta pri 90 °C ne utječe statistički značajno (p > 0,05) na promjene ispitivanih parametara, odnosno na antioksidacijski kapacitet bagremovog meda.

Abstract (english)

In this research, 30 samples of acacia honey (county of Varaždin, season 2011), untreated and heated for 5 minutes at 90 °C, were analysed. Total phenolic content was determined by the modified Folin-Ciocalteu method and antioxidant activity was determined using two methods, DPPH and FRAP. Average total phenolic content was 39,5±15,7 mg gallic acid/kg of honey for untreated samples, and 37,1±15,4 mg gallic acid/kg of honey for treated samples. Antioxidant acitvity determined by DPPH method was 114,1±40,4 mg mL-1 for untreated samples, and 155,2±64,7 mg mL-1 for treated samples. Antioxidant activity determined by FRAP method was 42,3±5,3 μM Fe(II) of the 10 % honey solution for untreated samples, and 45,6±4,8 μM Fe(II) of the 10 % honey solution for treated samples. The research showed that heating samples for 5 minutes at 90 °C has no statistically significant impact (p > 0,05) on the parameters measured, respectively the antioxidant activity of honey.

• Keywords: med; antioksidacijska aktivnost; ukupni fenoli; FRAP; DPPH
• Keywords (english): honey; antioxidative activity; total phenolic content; FRAP; DPPH
• Language: croatian
• URN:NBN: urn:nbn:hr:159:456638
• Study programme: Title: Food Safety Management; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane (magistar/magistra inženjer/inženjerka upravljanja sigurnošću hrane)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-05 11:25:59