Sastav bioaktivnih komponenata nekih nerafiniranih ulja

master's thesis

• Title (english): Composition of the bioactive components of some unrefined oils
• Author: Martina Pavleković
• Mentor: Dubravka Škevin (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Food Engineering); (Laboratory for Oil and Fat Technology); Zagreb
• Defense date and country: 2011-07-12, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Cilj ovog rada bio je usporediti sastav masnih kiselina te bioaktivnih komponenata šest nerafiniranih ulja (hladno prešano maslinovo, repičino, laneno, suncokretovo, lješnjakovo te nerafinirano jestivo bučino ulje) kako bi se potrošačima pružile dodatne informacije o tim uljima. Sastav masnih kiselina određuju svojstva ulja dok bioaktivne komponente (klorofili, tokoferoli i fenoli) djeluju kao antioksidansi u uljima, ali i u organizmu. Svi uzorci ulja zadovoljavaju osnovne parametre kvalitete osim bučinog koji sadrži veći udio slobodnih masnih kiselina od dopuštenog. Sastav masnih kiselina u analiziranim uzorcima maslinovog, repičinog, suncokretovog i bučinog ulja u skladu je s propisima iz Pravilnika, dok je sastav masnih kiselina lanenog i lješnjakovog ulja u skladu s literaturom. Repičino ulje, a posebice laneno ulje je bogato esencijalnim omega-3 masnim kiselinama. Kod bučinog ulja je ustanovljen najviši udio klorofila, a zatim redom kod repičinog i maslinovog. Lješnjakovo i suncokretovo ulje odlikuju se vrlo visokim udjelom tokoferola, dok je udio fenola u tim uljima nizak. Najviši udio fenolnih spojeva sadrži maslinovo ulje te je ono jedino ulje koje sadrži flavonoide i oleuropein. Repičino ulje također sadrži visoki udio fenolnih spojeva od kojih je najzastupljeniji kanolol. Antioksidacijska aktivnost je određena DPPH• metodom te je ustanovljeno da suncokretovo ulje ima najbolju sposobnost izbjeljivanja DPPH• radikala a najbolje sa antioksidacijskom aktivnosti koreliraju tokoferoli.

Abstract (english)

The aim of this work was to compare the composition of fatty acids and bioactive components of six unrefined oil (cold pressed olive, rapeseed, linseed, sunflower, hazelnut and unrefined edible pumpkin seed oil) in order to provide additional information about nutritive value of these oils. The composition of fatty acids determines the properties of oil while bioactive components (chlorophylls, tocopherols, and phenols) act as antioxidants in oils but they also have biological effect. All samples of oil fulfill the basic quality parameters acording to national regulations except pumpkin oil, which contains a higher amount of free fatty acids. The fatty acid composition in the analyzed samples of olive, rapeseed, sunflower oil and pumpkin oil is in accordance with national regulations, while the fatty acid composition of linseed oil and hazelnut oil is in accordance with the literature. Flaxseed oil is rich in essential omega-3 fatty acids. In pumpkin oil is established the highest amount of chlorophyll, folowed by olive and rapeseed oil. Hazelnut oil and sunflower oil are characterized with a high concentration of tocopherols and low concentration of phenols. Olive oil contains the highest amount of phenolic compounds, and it is the only oil that contains flavonoids and oleuropein. Rapeseed oil contains a high proportion of phenolic compounds with canolol as predominant phenolic compound. Antioxidant activity was determined by DPPH• method and found that sunflower oil has the best ability to bleach DPPH• radicals.

• Keywords: nerafinirana ulja; sastav masnih kiselina; tokoferoli; fenoli; antioksidacijska aktivnost
• Keywords (english): crude oil; fatty acid composition; tocopherols; phenols; antioxidant activity
• Language: croatian
• URN:NBN: urn:nbn:hr:159:799524
• 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: 2017-05-31 11:40:48