Utjecaj temperature i pH na stabilnost prirodnih prehrambenih bojila

master's thesis

• Title (english): Influence of temperature and pH on stability of food natural colorants
• Author: Marija Vaško
• Mentor: Suzana Rimac Brnčić (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Food Processes Engineering); Zagreb
• Defense date and country: 2015-09-24, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Nutrition

Abstract

Cilj ovog rada bio je odrediti utjecaj pH vrijednosti (pH 5 i pH 7) i temperature (50 i 70 C) na stabilnost prirodnih prehrambenih bojila ljubičaste, narančaste i plave boje kroz 180 min. Rezultati istraživanja pokazali su kako stabilnost ispitivanih prirodnih prehrambenih bojila ovisi o primijenjenoj temperaturi, duljini zagrijavanja i pH vrijednosti medija. Sva tri ispitivana prirodna prehrambena bojila pokazala su veću stabilnost pri nižim temperaturama zagrijavanja te pri nižoj pH vrijednosti. Kao najstabilnije ispitivano bojilo pokazalo se prirodno prehrambeno bojilo narančaste boje kod kojeg je ostatak apsorbancije nakon zagrijavanja kroz 180 min pri 50 ˚C i pri pH 5 iznosio 97,57 %. Najmanja stabilnost utvrđena je kod plavog prehrambenog bojila pri 70 ˚C i pH 7, a ostatak apsorbancije nakon 180 min iznosio je 15,42 %.

Abstract (english)

The aim of this study was to determine the influence of pH value (pH 5 and pH 7) and temperature (50 ˚C and 70 ˚C) on the stability of purple, orange and blue natural food colourants, through period of 180 minutes. Obtained results showed that the stability of the tested natural food colourants depends on the temperature, the heating duration and pH value of media. All three investigated natural food colorants showed higher stability at lower temperatures and lower pH values. The most stable colorant was the orange colored natural food colorant, with the remaining absorbance 97,57 %; after heating at 50 ˚C, during 180 minutes and pH value 5. Minimum stability was found in blue food colorant, at 70 °C and pH 7 and remaining absorbance was15,42 % after 180 minutes.

• Keywords: stabilnost; prirodna prehrambena bojila; pH vrijednost; zagrijavanje
• Language: croatian
• URN:NBN: urn:nbn:hr:159:979819
• Study programme: Title: Nutrition; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra nutricionizma (magistar/magistra nutricionizma)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-05-03 09:42:30