master's thesis
Effect of antioxidants on oxidative change of a mixture vegetable oils

Zrinka Grgurovac (2012)
Josip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Department of Food Technologies
Metadata
TitleUtjecaj antioksidansa na promjenu oksidacijske stabilnosti smjese biljnih ulja
AuthorZrinka Grgurovac
Mentor(s)Tihomir Moslavac (thesis advisor)
Abstract
Oksidacija lipida predstavlja vaţan problem koji utječe na jestiva ulja, budući je uzrok kvarenja te dovodi do značajnih promjena u kemijskim, senzorskim i nutritivnim svojstvima, rizik za zdravlje i ekonomske gubitke. U ovom radu istraţivan je utjecaj sintetskog antioksidansa propil galata (0,01%) i prirodnih antioksidanasa ekstrakta ruţmarina OxyLess.CS (0,1% i 0,3%) i ekstrakta zelenog čaja (0,1% i 0,3%) na oksidacijsku stabilnost smjese sezamovog ulja i ostalih vrsta biljnih ulja (50:50). Za ispitivanje oksidacijske stabilnosti korištene su sljedeće vrste biljnih ulja: sezamovo ulje, laneno ulje, ulje šafranike, ulje koštica groţĎa, biljno ulje s prirodnim ekstraktom bijelog luka, ekstra djevičansko maslinovo ulje. OdreĎivanje oksidacijske stabilnosti ulja, njihovih kombinacija, te utjecaj antioksidansa (propil galata, ekstrakta ruţmarina i ekstrakta zelenog čaja) provedeno je testom ubrzane oksidacije ulja – Oven testom (63 °C). Rezultat oksidacije ulja izraţen je peroksidnim brojem (Pbr) tijekom 4 dana testa. Dodatkom sezamovog ulja (50%) u druge vrste ispitivanih biljnih ulja došlo je do porasta stabilnosti smjese ulja prema oksidacijskom kvarenju osim kod smjese sa uljem šafranike I uljem koštica groţĎa. Prirodni antioksidansi ekstrakt ruţmarina OxyLess.CS i ekstrakt zelenog čaja efikasnije štiti smjesu ulja od oksidacijskog kvarenja u odnosu na dodatak sintetskog antioksidansa propil galata. Rezultati ispitivanja pokazuju da je veća efikasnost zaštite ovih smjesa ulja postignuta dodatkom udjela 0,3 % ekstrakta ruţmarina OxyLess.CS i ekstrakta zelenog čaja u odnosu na 0,1 %.
Keywordsoil vegetable oil oxidative stability propyl gallate rosemary extract green tea extract
Parallel title (English)Effect of antioxidants on oxidative change of a mixture vegetable oils
Committee MembersAndrija Pozderović
Tihomir Moslavac
Vedran Slačanac
Jurislav Babić
GranterJosip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Lower level organizational unitsDepartment of Food Technologies
PlaceOsijek
StateCroatia
Scientific field, discipline, subdisciplineBIOTECHNICAL SCIENCES
Food Technology
Engineering
Study programme typeuniversity
Study levelgraduate
Study programmeFood Technology and Process Engineering
Academic title abbreviationdipl. ing.
Genremaster's thesis
Language Croatian
Defense date2012-05-31
Parallel abstract (English)
Lipid oxidation has been recognised as the major problem affecting edible oils, as it is the cause of important deteriorative changes in their chemical, sensory and nutritional properties, health risk and economic losses. In this paper, monitored the influence of synthetic antioxidants propyl gallate (0,01%) and natural antioxidant: extracts of rosemary OxyLess.CS (0,1% and 0,3%) and green tea extract (0,1% and 0,3%), on the oxidative stability of sezame oil mixtures and other types of vegetable oil (50:50). To test the stability of oxidation were used the following types of vegetable oils: sezame oil, linseed oil, safflower oil, grape seed oil, vegetable oil with natural extracts of garlic, extra virgin olive oil. Determination of oxidation stability of oils and their combination, and the impact of antioxidant (propyl gallate, extracts of rosemary and green tea extract) conducted with a test of rapid oxidation of oils – Oven test (63 °C). The result of oil oxidation expressed peroxide value (PV) during 4 days of the test. The addition of sesame oil (50%) in other vegetable oils tested, there was an increase in the stability of a mixture of oil degradation by oxidation except for mixtures with safflower oil and grape seed oil. Natural antioxidants OxyLess.CS rosemary extract and green tea extract effectively protects the oil mixture from oxidative deterioration as compared to the addition of synthetic antioxidants propyl gallate.Test results show that the greater the protection efficiency of these compounds was achieved by adding oil of 0.3% OxyLess.CS rosemary extract and green tea extract compared to 0.1%.
Parallel keywords (Croatian)ulje biljna ulja oksidacijska stabilnost propil galat ekstrakt ružmarina ekstrakt zelenog čaja
Resource typetext
Access conditionAccess restricted to students and staff of home institution
Terms of usehttp://rightsstatements.org/vocab/InC/1.0/
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:109:922876
CommitterSanda Hasenay