Antioksidativna aktivnost zeolita u uljima

master's thesis

• Title (english): Antioxidative activity of zeolite in oils
• Author: Ivana Mandić
• Mentor: Vesna Lelas (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: 2004-11-18, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Antioksidansi se koriste kao dodaci hrani sa svrhom produženja njene trajnosti tijekom skladištenja. Njihova upotreba ograničena je brojnim čimbenicima kao što su zakonski propisi, njihova djelotvornost te cijena. Sve je veći interes za prirodnim antioksidansima uslijed uvjerenja potrošača da su oni zdravstveno sigurniji i bolji u odnosu na sintetske. Svrha ovoga rada je bila ispitati djelovanje tribomehanički aktiviranog zeolita u koncentraciji od 0,5; 1 i 2 % na oksidacijsku stabilnost suncokretovog i biljnog ulja tijekom skladištenja (90 dana uz i bez prisustva svjetlosti, pri 20˚C) te pri uvjetima ubrzanog kvarenja pri 60˚C (25 dana). Proces kvarenja masti uslijed oksidacijskih reakcija praćen je mjerenjem nastalih primarnih (peroksidni broj, spektrofotometrijsko određivanje nastalih hidroperoksida) i sekundarnih (anisidinski broj) produkata oksidacije. Dodatak tribomehanički aktiviranog zeolita suncokretovom i biljnom ulju doprinjeo je stabilnosti tih ulja. Prema analiziranim parametrima najbolji rezultati dobiveni su za suncokretovo ulje uz dodatak 1% TMAZ .

Abstract (english)

Antioxidants are used as food aditives in order to extend its lifetime during storage. The antioxidants to be used are determined by various factors including legislation, effectiveness and cost. Natural antioxidants have recently gained increased interest because of the belief that natural food ingredients are better and safer than synthetic ones. The aim of this work was to evaluate the antioxidant effectiveness of tribomechanically activated zeolites – TMAZ (concentration 0,5; 1 i 2 %) on oxidative stability of sunflower and vegetable oil during prolonged storage (exposed to daylight at room temperature or kept in dark at room temperature for 90 days) and under oxidative conditions (at 60˚C 25 days),. The oxidation process of oils was monitored by measuring the formation of primary (peroxide values, spectrophotometric investigation of formation of conjugated diene and tiene in the ultraviolet) and secondary (p-anisidine values) oxidation products. The addition of TMAZ to sunflower and vegetable oil improved the oxidative stability. The best results were obtained for sunflower oil with 1% TMAZ addition including all analyzed parameters.

• Keywords: biljno ulje; oksidacijska stabilnost; suncokretovo ulje; zeolit
• Keywords (english): oxidative stability; sunflower oil; vegetable oil; zeolite
• Language: croatian
• URN:NBN: urn:nbn:hr:159:246626
• Study programme: Title: Food Technology; specializations in: Food Engineering; Course: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo (diplomirani inženjer prehrambene tehnologije; smjer prehrambeno inženjerstvo)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-09-12 10:35:11