Utjecaj temperature na antioksidacijsku aktivnost meda

undergraduate thesis

• Title (english): Influence of temperature on antioxidant activity of honey
• Author: Lana Margetić
• 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: 2012-07-25, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Tijekom ovog istraživanja analizirana su 3 uzorka cvjetnog meda, netretirana te zagrijavana 5 minuta pri temperaturi od 90 °C. Određen je udio ukupnih fenola pomoću modificirane Folin-Ciocalteu metode, te antioksidacijska aktivnost pomoću FRAP metode. Udio ukupnih fenola kod netretiranih uzoraka iznosio je prosječno 80,2 ± 14,5 mg GAE/kg meda, a kod tretiranih 59,2 ± 10,2 mg GAE/kg meda. Antioksidacijska aktivnost, izražena kao FRAP vrijednost, kod netretiranih uzoraka iznosila je prosječno 214,10 ± 10,37 μM Fe (II) 10 %-tne otopine meda, dok je kod tretiranih uzoraka iznosila prosječno 139,07 ± 11,40 μM Fe (II) 10 %-tne otopine meda. Utvrđena je linearna korelacija između udjela ukupnih fenola i antioksidacijske aktivnosti određene FRAP metodom kod netretiranih uzoraka (r = 0,9607), kao i kod tretiranih uzoraka cvjetnog meda (r = 0,9406). Svi dobiveni rezultati upućuju na to da se antioksidacijska aktivnost meda smanjuje podvrgavanjem meda visokim temperaturama.

Abstract (english)

During this research, 3 samples of flower honey, were analysed, untreated and heated for 5 minutes at a temperature of 90 °C. Phenolic content was determined by the modified Folin-Ciocalteu method and antioxidant activity by FRAP method. Total phenolic content in untreated samples was in average 80,2 ±14,5 mg GAE / kg of honey, and in treated samples 59,2 ± 10,2 mg GAE / kg of honey. Antioxidant activity, expressed as FRAP value in untreated samples was in average 214,10 ± 10,37 μM Fe (II) 10% solution of honey, while the treated samples averaged 139,07 ± 11,40 μM Fe (II) 10% solution of honey. Linear correlation was established between total phenolic content and antioxidant activity by determined FRAP method in untreated samples (r = 0,9607), and treated samples of floral honey (r = 0,9406). All the results obtained suggest that the antioxidant activity of honey reduces with high temperatures.

• Keywords: cvjetni med; antioksidacijska aktivnost; temperatura; ukupni fenoli; FRAP metoda
• Keywords (english): floral honey; antioxidant activity; temperature; total phenols; FRAP method
• Language: croatian
• URN:NBN: urn:nbn:hr:159:391038
• 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: 2017-05-16 07:54:22