Utjecaj parametara proizvodnje na karakteristike repičinoga ulja s područja Republike Hrvatske

doctoral thesis

• Title (english): Influence of the production parameters on the characteristic of rapeseed oil from Croatia
• Author: Klara Kraljić
• Mentor: Dubravka Škevin (mentor)
• Committee member: Mirjana Hruškar (predsjednik povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; Zagreb
• Defense date and country: 2013-05-17, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology
• Universal decimal classification (UDC): 665 - Oils. Fats. Waxes. Adhesives. Gums. Resins

Abstract

Cilj ovog istraživanja bio je odrediti svojstva repičinoga ulja proizvedenoga iz kultivara koji se uzgajaju na području Republike Hrvatske, te odrediti utjecaj načina proizvodnje sirovoga ulja kao i procesa rafinacije na kvalitetu, sastav masnih kiselina, udio bioaktivnih komponenata te na oksidacijsku stabilnost repičinoga ulja. Rezultati su pokazali kako je udio dominantnih masnih kiselina, sastav i udio sterola, karotenoida i tokoferola odlika pojedinog kultivara, a klimatske prilike značajno utječu na varijaciju rezultata navedenih parametara. U početnoj fazi razvoja sjemena stresni uvjeti uzrokuju smanjenje udjela karotenoida i α-tokoferola, ali povećanu sintezu plastokromanola-8 i fenolnih spojeva. Način proizvodnje ulja značajno utječe na udio i sastav negliceridnih spojeva repičinoga ulja. Kondicioniranjem sjemena znatno se povećava udio sterola i pigmenata, γ-tokoferola i ukupnih tokoferola. Najzastupljeniji fenolni spoj je kanolol čiji se udio kondicioniranjem povećava do 56 puta. Ulja proizvedena ekstrakcijom organskim otapalom sadrže više sterola i α-tokoferola u odnosu na ulja proizvedena prešanjem. Rafinacijom repičinoga ulja smanjuje se udio sterola, tokoferola, a posebno fenola, dok kanolol u potpunosti nestaje. Međutim, tijekom rafinacije dolazi do sinteze fenilindana, specifičnog spoja rafiniranoga jestivoga repičinoga ulja koji se odlikuje snažnim antioksidacijskim djelovanjem.

Abstract (english)

The aim of this study was to determine characteristics of the rapeseed oil produced from cultivars grown in Croatia, and also to determine the affect of production parameters on the quality, fatty acid composition, amount of bioactive compounds and oxidative stability of the oil. Results have shown that the composition of dominant fatty acids, content and composition of sterols, catotenoids and tocopherols is a characteristic of a cultivar but those parameters are additionaly affected by climate conditions. Stressful conditions for the plant in the early stages of seed development decrease amount of carotenoids and α-tocopherol, but cause increased synthesis of the plastochromanol-8 and polyphenolic components. Amount and composition of nongliceride compounds was significantly influenced by oil production parameters. Conditioning rapeseed significantly increased amounts of sterols, pigments, γ-tocopherol and total tocopherols. The dominant phenolic component is canolol and conditioning increased its amount up to 56-fold. Oils produced by extraction with solvent have higher amount of sterols and α-tocopherol than pressed oils. Refining reduces amount of sterols, tocopherols and especially polyphenols, while canolol disappears completely. However, during refining process phenylindane is synthesized, a specific component of refined edible rapeseed oil which is characterized with strong antioxidant activity.

• Keywords: repičino ulje; masne kiseline; steroli; tokoferoli; fenoli; kanolol; fenilindan
• Keywords (english): rapeseed oil; fatty acids; sterols; tocopherols; polyphenols; canolol; phenylindane
• Language: croatian
• URN:NBN: urn:nbn:hr:159:668950
• Promotion: 2013-09-22
• Study programme: Title: Food Technology; Study programme type: university; Study level: postgraduate; Academic / professional title: doktor/doktorica znanosti (doktor/doktorica znanosti)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2018-05-17 10:28:03