Utjecaj ultrazvuka visokog intenziteta na slobodne fenolne spojeve i antioksidacijsku aktivnost bučine pogače, heljde i prosa

master's thesis

• Title (english): Influence of high intensity ultrasound treatment on free phenolic compounds and antioxidant activity of pumpkinseed cake, buckwheat and millet
• Author: Martina Braje
• Mentor: Nikolina Čukelj (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Cereal Chemistry and Technology); Zagreb
• Defense date and country: 2017, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog istraživanja bio je ispitati utjecaj ultrazvuka visokog intenziteta na učinkovitost oslobađanja fenolnih spojeva iz bučine pogače, heljde i prosa. Također je ispitivan i utjecaj ultrazvuka visokog intenziteta na antioksidacijski kapacitet navedenih sirovina. Tretman je proveden direktnim uranjanjem ultrazvučne sonde (promjera 22 mm, 400 W, 24 kHz) pri 100 % amplitudi, a vrijeme tretmana bilo je 5, 10 i 20 minuta. Sadržaj ukupnih fenolnih spojeva određivan je Folin-Ciocalteu metodom, antioksidacijski kapacitet spektrofotometrijski dok je rutin u heljdi određen tekućinskom kromatografijom visoke djelotvornosti. Ultrazvuk visokog intenziteta je imao različiti utjecaj ovisno o vrsti tretiranog uzorka te vremenu tretmana. Najveći ekstrakcijski prinos ukupnih fenola i najveća antioksidacijska aktivnost za heljdu ostvarena je tretmanom od 10 minuta. Ultrazvuk visokog intenziteta je imao negativan ili neutralan utjecaj na ukupne fenole i antioksidacijsku aktivnost kod tretiranih uzorka bučine pogače i prosa te na sadržaj rutina. Iako je ultrazvuk visokog intenziteta netermalna metoda, njegov efekt zagrijavanja ima utjecaj na oslobađanje fenolnih spojeva i antioksidacijsku aktivnost.

Abstract (english)

This research aimed to investigate the effect of high intensity ultrasound on the release of phenolic compounds from buckwheat, millet and pumpkinseed cake, as well as to determine their antioxidant activity. The treatment was performed at the constant power of ultrasound (400 W) and the amplitude of 100%,while the extraction time was 5, 10 and 20 minutes. Phenolics were measured using the Folin-Ciocalteu method, the antioxidant activity was determined spectrometric, while rutin in buckwheatwas determined by the high performance liquid chromatography. The ultrasound had a different effect depending on the type of the treated sample and treatment time. The highest total phenolics and antioxidant capacity of buckwheat was achieved after the 10 minute treatment. The ultrasound had a negative or neutral effect depends of treated material on total phenolics and antioxidant activity of millet and pumpkinseed cake and on the rutin content. The heating of the sample, which comes as a side effect of high intensity ultrasound had a significant effect on the release of phenolic compounds and antioxidant activity.

• Keywords: bučina pogača; heljda; proso; ultrazvuk visokog intenziteta; ukupni fenolni spojevi; antioksidacijski kapacitet
• Keywords (english): pumpkinseed cake; buckwheat; millet; high intensity ultrasound; total phenolic; antioxidant activity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:149675
• Study programme: Title: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka prehrambenog inženjerstva (magistar/magistra inženjer/inženjerka prehrambenog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-11-08 12:59:56