Utjecaj prirodnih antioksidanasa na svojstva i održivost djevičanskog maslinovog ulja

master's thesis

• Title (english): The influence of antioxidants on characteristics and stability of virgin olive oil
• Author: Lidija Bačić
• Mentor: Dubravka Štrucelj (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: 2005-06-16, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Utjecaj dodatka lecitina soje (0,5%) i maceriranih listića ružmarina (5%) na svojstva i održivost djevičanskih maslinovih ulja, iz domaćih sorti Oblica i Buharica berbe 2002/03. godine s otoka Brača, ispitivan je tijekom 6 mjeseci. Određivani su osnovni parametri kakvoće, tj. hidrolitičke i oksidacijske promjene, provedena je spektrofotometrijska analiza, određeni su pigmenti i indeks boje, udjel fenolnih spojeva, intenzitet gorčine, te se posebno odredila održivost ulja bez i s dodatkom lecitina i preparata ružmarina u uvjetima Rancimat testa pri 120°C. Ulja iz Oblice i Buharice tijekom cijelog istraživanja zadovoljavala su kriterije kategorije „djevičansko maslinovo ulje ekstra“. Dodatak lecitina nije utjecao na udjel slobodnih masnih kiselina, ali je nakon skladištenja od 6 mjeseci peroksidni broj bio najniži u uzorcima s lecitinom. Dodatak preparata ružmarina povisio je udjel fenolnih spojeva, jer neki fenolni spojevi iz ružmarina prelaze u ulje. Antioksidacijski spojevi ružmarina su najvjerojatnije sinergisti antioksidansima iz maslinovog ulja. Dodatak lecitina i ružmarina znatno produžuju održivost ulja.

Abstract (english)

The influence of soyabean lecithine (0,5%) and macerated rosemary leaves (5%) on the characteristics and stability of virgin olive oil obtained from domestic olive varieties, Oblica and Buharica, harvested in 2002/03 on the island of Brač, has been investigatet during the period of 6 months. Basic quality parameters have been determined e.g. the hydrolitical and oxidative changes, a spectrophotometrical analysis has been completed, pigments and color index, the content of phenolic compounds, intensity of bitterness and especially the stability of the oil with and without the addition of lecithine and rosemary in Rancimat conditions at 120ºC have been determined. Throughout the whole period Oblica and Buharica oils fulfilled the criteria of the category of „virgin olive oil extra“. The additon of lecithine did not have any influence on the content of free fatty acids, but after 6 months of storage the peroxide value was the lowest in the samples with lecithine. The addition of rosemary has increased the content of phenolic compounds because some of the phenolic compounds transfer to oil. Antioxidative compounds of rosemary are probably synergists to antioxidants in olive oil. The addition of lecithine and rosemary extends the stability of oil considerably.

• Keywords: antioksidansi; djevičansko maslinovo ulje; lecitin; održivost; ružmarin
• Keywords (english): antioxidans; lecithin; rosemary; shelf-life; virgin olive oil
• Language: croatian
• URN:NBN: urn:nbn:hr:159:492523
• 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: 2017-09-13 09:33:47