professional thesis
The impact of pumpkin seed processing conditions on oil yield and oxidation stability

Tanja Mađarević Pavetić (2015)
Josip Juraj Strossmayer University of Osijek
FACULTY OF FOOD TECHNOLOGY
Department of Food Technologies
Metadata
TitleUtjecaj uvjeta prerade koštice buče na iskorištenje i oksidacijsku stabilnost ulja
AuthorTanja Mađarević Pavetić
Mentor(s)Tihomir Moslavac (thesis advisor)
Stela Jokić (thesis advisor)
Abstract
U ovom radu istraživan je utjecaj uvjeta prerade bučinih koštica na iskorištenje i oksidacijsku stabilnost ulja. Od procesnih parametara prešanja bučine koštice pomoću pužne preše, ispitivan je utjecaj frekvencije elektromotora, veličina otvora glave preše i temperatura zagrijavanja glave preše na iskorištenje ulja. Također, primjenom suvremene metode ekstrakcije superkritičnim CO2 potpuno je ekstrahirano zaostalo ulje iz pogače nakon procesa prešanja. Za stabilizaciju proizvedenog bučinog ulja korišteni su prirodni antioksidansi ekstrakt ružmarina i ekstrakt zelenog čaja, te sinergisti askorbinska i limunska kiselina. Oksidacijska stabilnost hladno prešanog bučinog ulja, sa i bez dodanog antioksidansa i sinergista, ispitivana je primjenom Schaal Oven testa. Najbolje antiksidacijsko djelovanje kod ispitivanog ulja postignuto je dodatkom mješavine prirodnih antioksidanasa ekstrakta ružmarina i ekstrakta zelenog čaja uz sinergist askorbinsku kiselinu. Veličina otvora glave preše, temperatura zagrijavanja glave preše i frekvencije elektromotora imali su značajan utjecaj na iskorištenje ulja tijekom hladnog prešanja bučine koštice. Primjenom metode ekstrakcije superkritičnim CO2 moguće je potpuno ekstrahirati zaostalo ulje iz pogače nakon procesa prešanja što je iznimno važno u industrijskoj proizvodnji ulja, jer se time postiže gotovo potpuno iskorištenje sirovine i ostvaruju se minimalni gubitci u proizvodnom procesu.
Keywordsoil oxidation stability supercritical CO2 extraction
Parallel title (English)The impact of pumpkin seed processing conditions on oil yield and oxidation stability
Committee MembersDrago Šubarić
Tihomir Moslavac
Stela Jokić
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
Food Safety and Quality
Study programme typeuniversity
Study levelpostgraduate specialist
Study programmeFood Safety and Quality
Academic title abbreviationuniv. spec. techn. aliment.
Genreprofessional thesis
Language Croatian
Defense date2015-12-23
Parallel abstract (English)
The impact of pumpkin seed processing conditions on oil yield and oxidation stability was researched in this paper. The following processing parameters of pumpkin seed pressing using a screw press on oil yield were studied for their impact: electromotor frequency, nozzle size, and press head temperature. Moreover, by implementing the recent method of supercritical CO2 extraction all the remaining oil from the cake was extracted. The resulting pumpkin seed oil was stabilized by using natural antioxidants, rosemary extract and green tea extract, and ascorbic and citric acid synergists. The Schaal Oven test was used to test the oxidation stability of cold pressed pumpkin seed oil with and without antioxidants and synergists. The best antioxidant effects observed were achieved by adding a mixture of rosemary and green tea extracts and ascorbic acid synergist. Nozzle size, press head temperature, and electromotor frequency had a significant impact on oil yield during pumpkin seed cold pressing. Supercritical CO2 extraction enabled a complete extraction of oil from the cake after the pressing procedure, which is extremely important in industrial oil production as it enables an almost complete raw material yield, and minimal losses in the production process.
Parallel keywords (Croatian)ulje oksidacijska stabilnost ekstrakcija superkritičnim CO2
Resource typetext
Access conditionOpen access
Terms of usehttp://rightsstatements.org/vocab/InC/1.0/
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:109:977023
CommitterIvana Šuvak