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U ovom diplomskom radu ispitivan je utjecaj procesnih parametara prešanja na iskorištenje hladno prešanog konopljinovog ulja. Prešanje sjemenki konoplje provedeno je na kontinuiranoj pužnoj preši u laboratoriju. Tijekom proizvodnje ulja mijenjali su se procesni parametri: veličina otvora glave preše, temperatura glave preše te frekvencija elektromotora. Finalno hladno prešano ulje dobilo se nakon provedene sedimentacije i vakuum filtracije. U proizvedenom ulju određeni su osnovni parametri kvalitete: peroksidni broj, slobodne masne kiseline, vlaga te udio netopljivih nečistoća. Na proizvedenom hladno prešanom ulju ispitan je i utjecaj dodatka antioksidanasa i sinergista na oksidacijsku stabilnost ulja Schaal Oven testom pri 63 °C. Od antioksidanasa korišteni su ekstrakt ružmarina, ekstrakt kadulje, ekstrakt zelenog čaja, mješavina tokoferola, kafeinska kiselina, a od sinergista askorbinska i limunska kiselina. Rezultati su pokazali da promjena procesnih parametara prešanja utječe na iskorištenje ulja, a dodaci antioksidanasa i sinergista doprinose stabilizaciji i održivosti ulja. In this thesis, the influence of process parameters on the use of cold-pressed hemp oil was investigated. The pressing of hemp seeds was carried out on a continuous screw press in the laboratory. During oil production, the process parameters changed: the size of the press head opening, the temperature of the press head and the frequency of the electric motor. The final cold-pressed oil was obtained after sedimentation and vacuum filtration. The basic quality parameters of cold-pressed oil are also determined in the oil: peroxide value, free fatty acids, moisture and the proportion of insoluble impurities. The influence of the addition of antioxidants and synergists on oxidizing oils was also tested on the produced cold-pressed oil using the oven stability test at 63 °C. Rosemary extract, sage, green tea extract, tocopherol mixture, caffeic acid are used as antioxidants, and ascorbic and citric acid are used as synergists. The results showed that the change in process parameters affects the utilization of the oil, and the addition of antioxidants and synergists contribute to the stabilization and sustainability of the oil.

Buča (Cucurbita pepo L.) je jednogodišnja biljka koja potječe iz Amerike, a sastoji se od mesnatog dijela ploda i koštice. Koštica može biti s ljuskom i bez ljuske. U ovom radu istraživan je utjecaj vrste pužnice i procesnih parametara na iskorištenje bučinog ulja. Proizvedeno je hladno prešano bučino ulje na kontinuiranoj laboratorijskoj pužnoj preši. Procesni parametri koji su se mijenjali prilikom prešanja su: frekvencija elektromotora, temperatura grijača glave preše i nastavak za izlaz pogače. Korištena su tri tipa pužnice s različitom dubinom navoja. Ispitani su osnovni parametri kvalitete ulja: slobodne masne kiseline, peroksidni broja, udio vode i udio netopljivih nečistoća. Analitički je određen udio ulja u bučinim košticama i pogači kako bi se odredila efikasnost proizvodnje ulja. Prešanjem bučine koštice kod veće temperature glave preše, manje frekvencije elektromotora i manjeg nastavka za izlaz pogače proizvedena je veća količina ulja. Primjenom pužnice dubine navoja 5 mm dobivena je veća količina ulja u odnosu na 8 mm i 10 mm. Pumpkin (Cucurbita pepo L.) is an annual plant that originate from America and it is made of pulpy part of fruit and pits. A pit can be with a husk or without one. The aim of this research was to analyze the influence of screw press type and process parameters on the utilisation of pumpkin seed oil. It was produced cold pressed pumpkin seed oil on continuous laboratory screw press. The process parameters, which were changed during the pressing process, are: the frequency of electric motor, temperature of the press heating head and nozzle size. There were used three screw press types with different thread depth. There were questioned the basic quality oil parameters such as free faty acid, peroxide value, water content and proportion of insoluble impurities. Oil extraction by Soxhlet method determined the proportion of oil in pumpkin seeds and cake so that it could be defined oil production efficiency. Analytically it was determined content of oil in pumpkin pits and nozzle so it could be determined oil production efficiency. With pressing pumpkin pit at higher press head temperatures, less frequency of electric motor and smaller nozzle size it was produced a larger amount of oil. Using screw press with thread depth of 5 millimeters it was gained a larger amount of oil in comparsion with 8 millimeters and 10 millimeters.

U ovom radu istraživan je utjecaj procesnih parametara prešanja sikavice na efikasnost proizvodnje hladno prešanog ulja te njegovu kvalitetu. Prije prešanja određen je udio ulja u sjemenkama sikavice (26,06 %). Prešanje sjemenki sikavice provedeno je na laboratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja. Prešanjem sikavice dobivena su tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom procesa prešanja mijenjali su se procesni parametri: temperatura grijača glave preše kod izlaza pogače, frekvencija elektromotora i nastavak koji regulira veličinu otvora glave preše. Nakon završetka prešanja provedeno je prirodno taloženje od 14 dana dobivenog sirovog ulja, a potom vakuum filtracija. Primjenom standardnih metoda određeni su parametri kvalitete ulja: slobodne masne kiseline, peroksidni broj, udio vlage i isparljivih tvari te udio netopljivih nečistoda. Metodom po Soxhlet-u određivana je količina ulja u sjemenkama i zaostalog ulja u pogači kako bi se odredila efikasnost proizvodnje hladno prešanog ulja sikavice. Rezultati pokazuju da je primjenom nastavka za izlaz pogače promjera 10 mm, frekvencije elektromotora 25 Hz i temperature zagrijavanja glave preše 110 °C dobiven vedi volumen sirovog i hladno prešanog ulja sikavice, niži udio zaostalog ulja u pogači te vedi stupanj djelovanja preše. In this study we have monitored the influence of process parameters on the efficiency of the pressing Milk thistle seed production of cold pressed oil and its quality. Before pressing, the oil content of Milk thistle seeds was determined (26.06%). Milk thistle seeds pressing was carried out on laboratory screw press for production of cold pressed vegetable oils. Three products were obtained by pressing Milk thistle seeds: unpirified crued oil, oil sludge and cake. During the pressing process, the process parameters changed: temperature pf the press heating head at the outlet of cake, the frequency of the electric motors and the extension that regulates the size of the opening press head. After the process of pressing, natural sedimentation of 14 days and vacuum filtration were conducted on unpurified crude oil. By using standard methods we determineted the parametars of oil quality: free faty acid, peroxide value, the proportion of moisture and volatile matter and insoluble impuritie. The amount of oil in the seeds and residual oil in the cake was determined by the Soxhlet method to determine the production efficiency of cold-pressed Milk thistle oil. After applaying the 10 mm press head for cake outcome, 20 Hz frequency of electric motors, and 110 °C heating temperature of press head, the bigger volume of crude and Milk thistle oil was obtained as well as smaller volume of residual oil in the cake and larger level of press operation.

Cilj ovog rada je ispitati utjecaj procesnih parametara hladnog prešanja sjemenki noćurka s kontinuiranom pužnom prešom na iskorištenje ulja. Prije prešanja određen je udio ulja u sjemenkama noćurka i udio vlage. Prešanjem sjemenki noćurka dobivena su tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom procesa prešanja mijenjali su se procesni parametri: veličina nastavka za izlazak pogače (8 mm, 10 mm, 12 mm), temperatura grijača glave preše kod izlaza pogače (90 °C, 100 °C, 110 °C) i frekvencija elektromotora (25 Hz, 30 Hz, 40 Hz). Nakon završetka prešanja provedeno je prirodno taloženje u trajanju 21 dan dobivenog sirovog ulja, a potom vakuum filtracija. Na proizvedenom hladno prešanom ulju noćurka određen su osnovni parametri kvalitete: peroksidni broj, slobodne masne kiseline, udio vode i udio netopljivih nečistoća. Metodom po Soxhlet-u određena je količina ulja u sjemenkama i zaostalog ulja u pogači kako bi se odredila efikasnost proizvodnje hladno prešanog ulja noćurka. The aim of this master thesis is to examine how different process parameters of cold pressing of evening primrose seeds with continuous screw press influence oil utilization. Before pressing, the oil content in the primrose seeds (21,50 %) and moisture content (6,90%) were determined. By pressing primrose seeds, three products were obtained: crude oil, oil sludge and cake. During the pressing process, process parameters were changed: extension that regulates the size of the opening press head (8 mm, 10 mm, 12 mm), temperature of the press heating head at the outlet of cake (90 °C, 100 °C, 110 °C) and the frequency of electric motors (25 Hz, 30 Hz, 40 Hz). After pressing has finished, natural sedimentation of 21 days and vacuum filtration were conducted on crude oil. Basic quality parameters of produced cold-pressed primrose oil were determined: peroxide number, free faty acids, water content and the proportion of insoluble impurities. Based on Soxhlet method, the amount of oil in the seeds and the residual oil in the cake were determined in order to define the efficiency of the production of cold-pressed evening primrose oil.

U ovom radu istraživan je utjecaj procesnih parametara hladnog prešanja sjemenki crnog kima na proizvodnju ulja te njegovu kvalitetu. Prešanje sjemenki crnog kima provedeno je na laboratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja te su tako dobivena tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom prešanja mijenjani su procesni parametri: temperatura glave preše, brzina pužnice, te nastavak za izlaz pogače. Nakon prešanja provedeno je prirodno taloženje dobivenog sirovog ulja te filtriranje. Primjenom standardnih metoda određeni su parametri kvalitete ulja: peroksidni broj, slobodne masne kiseline, udio netopljivih nečistoća te udio vlage i hlapljivih tvari. Kako bi se odredila efikasnost proizvodnje hladno prešanog ulja crnog kima provedeno je ispitivanje udjela ulja u pogači metodom po Soxhlet-u. Rezultati pokazuju da je primjenom nastavka za izlaz pogače veličine 6 mm, temperature 110 °C te frekvencije elektromotora 20 Hz dobivena najveća količina sirovog i finalnog hladno prešanog ulja crnog kima. In this study we have monitored the influence of process parameters on the efficiency of the pressing black cumin seed production of cold pressed oil and its quality. Black cumin seeds pressing was carried out on laboratory screw press for production of cold pressed vegetable oils. Three products were obtained by pressing black cumin seeds: unpurified crude oil, oil sludge and cake. During the pressing process, the process parameters changed: temperature pf the press heating head at the outlet of cake, the frequency of the electric motors and the extension that regulates the size of the opening press head. After the process of pressing, natural sedimentation and vacuum filtration were conducted on unpurified crude oil. By using standard methods, we determined the parameters of oil quality: peroxide value, free fatty acid, the proportion of moisture and volatile matter and insoluble impurities. The amount of oil in the seeds and residual oil in the cake was determined by the Soxhlet method to determine the production efficiency of cold-pressed black cumin oil. The results show that the highest amount of crude and final cold-pressed black cumin oil was obtained by applying a 6 mm extension that regulates the size of the opening press head with a temperature of 110 ° C and a frequency of 20 Hz.

Zadatak diplomskog rada bio je ispitati utjecaj vrste pužnice i procesnih parametara prešanja sjemenki sikavice na iskorištenje hladno prešanog ulja. Hladno prešano ulje sikavice proizvedeno je na kontinuiranoj pužnoj preši. Ispitan je utjecaj dvije vrste pužnice sa različitom dubinom navoja. Prilikom procesa prešanja mijenjali su se procesni parametri: temperatura grijača glave preše, frekvencija elektromotora i nastavak za izlaz pogače. Na proizvedenom hladno prešanom ulju sikavice ispitani su osnovni parametri kvalitete: peroksidni broj, slobodne masne kiseline, udio vode, udio netopljivih nečistoća i utvrđena je sukladnost s Pravilnikom o jestivim uljima i mastima. The aim of this research was to examine the influence of screw press type and process parameters of pressing Milk Thistle Seeds on the utillsation of cold pressed oil. Cold pressed Milk Thistle Seed oil was produced with a continuous screw press. The influence of two types of screw press with different thread depths was examined. During the pressing process, the process parameters were changed: temperature of the press heating head, the frequency of electric motor and output cake thickness. The basic quality parameters that were tested on the produced cold pressed Milk Thistle Seed oil: peroxide value, free faty acid, water content, proportion of insoluble impurities and compliance with the Ordinance on edible oils and fats was determined.

Zadatak diplomskog rada je ispitati utjecaj frekvencije elektromotora tijekom prešanja sjemenke konoplje sorte Finola na iskorištenje ulja. Na proizvedenom hladno prešanom konopljinom ulju ispitan je utjecaj dodatka prirodnih antioksidansa i sinergista na promjenu oksidacijske stabilnosti ili održivosti ulja. Od prirodnih antioksidansa korišteni su ekstrakt ružmarina, ekstrakt kadulje, ekstrakt maslinove komine i katehin. Kao sinergist korištene su askorbinska i limunska kiselina. Efikasnost antioksidansa i sinergista u stabilizaciji ulja određena je Schaal Oven testom oksidacijske stabilnosti kod konstantne temperature 63 °C. Rezultati ispitivanja stabilnosti ulja prikazani su vrijednostima peroksidnog broja tijekom šest dana provedbe testa. Rezultati ispitivanja pokazuju da se veće iskorištenje konopljinog ulja postiže kod manjeg nastavka za izlaz pogače, manje frekvencije elektromotora i veće temperature glave preše. Ekstrakt ružmarina u kombinaciji sa sinergistom askorbinskom kiselinom najbolje štiti ulje konoplje od oksidacijskog kvarenja. The aim of this thesis is to examine the influence of the frequency of electric motors during the pressing of hemp seed variety Finola on oil yield. The effect of the addition of natural antioxidants and synergists on altering the oxidative stability or sustainability of the oil was tested on the produced cold pressed hemp oil. Natural antioxidants used were rosemary extract, sage extract, olive pomace extract and catechin. Ascorbic and citric acids were used as synergists. The effectiveness of antioxidants and synergists in oil stabilization was determined by the Schaal Oven oxidation stability test at a constant temperature of 63 °C. The results of the oil stability test are shown by peroxide values during the six days of the test. Test results show that greater use of hemp oil is achieved with a smaller batch output, lower electric motor frequency and higher press head temperatures. Rosemary extract in combination with ascorbic acid synergist best protects hemp oil from oxidative spoilage.

Postupkom hladnog prešanja iz sjemenki maka (Papaver somniferum L.) dobije se kvalitetno jestivo ulje. Cilj ovog rada bio je ispitati utjecaj procesnih parametara prešanja sjemenki maka na efikasnost proizvodnje hladno prešanog makovog ulja te njegovu kvalitetu. Prilikom prešanja mijenjani su sljedeći procesni parametri: brzina pužnice (frekvencija elektromotora), temperatura zagrijavanja glave preše i nastavak za izlaz pogače. Prešanje je provedeno sa kontinuiranom pužnom prešom. Primjenom standardnih metoda određeni su osnovni parametri kvalitete proizvedenog hladno prešanog makovog ulja. Rezultati ispitivanja pokazuju da procesni parametri hladnog prešanja značajno utječu na iskorištenje makovog ulja. Veće iskorištenje sirovog ulja i hladno prešanog makovog ulja postignuto je kod temperature zagrijavanja glave preše 100 °C, frekvencije elektromotora 25 Hz i nastavka za izlaz pogače 6 mm. The cold pressing of the poppy seeds (Papaver somniferum L.) is used to obtain high-quality edible oil. The aim of this study was to investigate the influence of process parameters of pressing poppy seeds on efficiency of production of cold-pressed poppy oil and its quality. Following process parameters were investigated: frequency, temperature of head presses, and nozzle size. Pressing was carried out with a continuous screw press. Using standard methods, the basic quality parameters of produced cold pressed poppy oil were determined. The results showed that the process parameters of cold pressing had a significant impact on the yield of poppy oil. Higher yield of crude oil and cold-pressed poppy oil was obtained at a temperature of heating head presses 100 °C, frequency of 25 Hz and using nozzle size of 6 mm.

Postupkom hladnog prešanja iz sjemenki maka (Papaver somniferum L.) dobije se kvalitetno jestivo ulje. Cilj ovog rada Bio je ispitati utjecaj procesnih parametara prešanja sjemenki maka na efikasnost proizvodnje hladno prešanog makovog ulja te njegovu kvalitetu. Prilikom prešanja mijenjani su sljedeći procesni parametri: brzina pužnice (frekvencija elektromotora), temperatura zagrijavanja glave preše i nastavak za izlaz pogače. Prešanje je provedeno sa kontinuiranom pužnom prešom. Primjenom standardnih metoda određeni su osnovni parametri kvalitete proizvedenog hladno prešanog makovog ulja. Rezultati ispitivanja pokazuju da procesni parametri hladnog prešanja značajno utječu na iskorištenje makovog ulja. Veće iskorištenje sirovog ulja i hladno prešanog makovog ulja postignuto je kod temperature zagrijavanaj glave preše 100 oC, frekvencije elektromotora 25 Hz i nastavka za izlaz pogače 6 mm.

U ovom radu istraživan je utjecaj procesnih parametara prešanja maka na efikasnost proizvodnje hladno prešanog makovog ulja te njegovu kvalitetu. Prešanje sjemenki maka provedeno je na laboratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja. Prešanjem maka dobivena su tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom prešanja mijenjali su se procesni parametri: temperatura glave preše, brzina pužnice, te nastavak za izlaz pogače. Nakon prešanja provedeno je prirodno taloženje dobivenog sirovog ulja te filtriranje. Primjenom standardnih metoda određeni su parametri kvalitete ulja: preoksidni broj, slobodne masne kiseline, udio netopljivih nečistoća te udio vlage i hlapljivih tvari. Kako bi se odredila efikasnost proizvodnje ulja provedeno je ispitivanje udjela ulja u pogači metodom po Soxhlet-u. Primjenom nastavka za izlaz pogače promjera 5 mm, frekvencije elektromotora 20 Hz i temperature zagrijavanja glave preše 100 °C dobiven je veći volume sirovog i finalnog makovog ulja, niži udio zaostalog ulja u pogači te većo stupanj djelovanja preše. In this study we have monitored the influence of process parameters on the efficiency of the pressing poppy seed production of cold pressed poppy oil and its quality. Poppy seeds pressing was carried out on laboratory screw press for production of cold pressed vegetable oils. Pressed poppy produced three products: unpirified crued oil, oil sludge and cake. During the pressing process, the process parameters had been changed: the temperature of presses head, frequency and output cake thickness. After the process of pressing, natural sedimentation and filtration were conducted on unpurified crude oil. By using standard methods we determineted the parametars of oil quality: peroxide value, free faty acid, the proportion of insoluble impurities as well as moisture and volatile matter. In order to determine the effieciency of oil production we examined oil share in a cake by using Soxhlet method. After applying the 5 mm press head for cake outcome, 20 Hz electromotor and 100 °C heating temperature of press head, the bigger volume of crude and final poppy oil was obtained as well as smaller volume of residual oil in the cake and larger level of press operation.

U ovom radu istraživan je utjecaj procesnih parametara prešanja oraha na efikasnost proizvodnje hladno prešanog orahovog ulja. Prešanje jezgre oraha se provodilo na laboratorijskoj kontinuiranoj pužnoj preši. Prilikom prešanja mijenjali su se procesni parametri: temperature glave preše, brzina pužnice te nastavak za izlaz pogače. Nakon prešanja provedeno je prirodno taloženje sedam dana i centrifugiranje sirovog ulja. Primjenom standardnih metoda određeni su parametri kvalitete ulja: peroksidni broj, slobodne masne kiseline, udio netopljivih nečistoća i udio vlage i hlapljivih tvari. Također, ispitivana je oksidacijska stabilnost proizvedenog hladno prešanog orahovog ulja s i bez dodatka antioksidansa. Korišten je test ubrzane oksidacije ulja (Oven test). Dobiveni rezultati pokazuju da procesni parametri prešanja utječu na iskorištenje ulja. Ekstrakt ružmarina i ekstrakt zelenog čaja dodani u koncentraciji 0,1 % i 0,2 % značajno povećavaju otpornost orahovog ulja prema oksidacijskom kvarenju, u odnosu na druge ispitane antioksidanse. This study researches the influence of process parameters on the efficiency of cold pressed walnut oil production. The walnut core pressing was carried out in a laboratory continuous worm screw press. The process parameters were varied during the pressing: the temperature of the press head, frequency and cake output extensions. After pressing, natural sedimentation was conducted for seven days and centrifugation of crude oil. Walnut oil quality parameters were determined by applying standard methods: peroxide value, free fatty acids, the proportion of insoluble impurities and moisture, and volatile substance. Effect of added antioxidants on the oxidative stability of produced cold pressed walnut oil is also examined, by applying the accelerated oxidation test (Oven test). Obtained results showed the effect of process parameters on the yield of the oil. Compared to other examined antioxidants, rosemary extract and green tea extract added in a concentration of 0.1% and 0.2% are significantly increasing the resistance of walnut oil to oxidative deterioration.

Salvia hispanica L. (chia) je biljka iz porodice Labiatae, čije sjemenke sadrže 25-35 % ulja i imaju visok sadržaj omega-3 linolenske masne kiseline. Hladno prešano ulje chie proizvedeno je postupkom prešanja sjemenki chie na kontinuiranoj pužnoj preši, pri čemu su dobivena tri proizvoda: sirovo ulje, uljni talog i pogača. Nakon prešanja provedeno je prirodno taloženje dobivenog sirovog ulja i vakuum fltracija. U ovom radu ispitivan je utjecaj procesnih parametara prešanja chie (temperatura zagrijavanja glave preše, veličina otvora glave preše i brzina pužnice - frekvencija elektromotora) na iskorištenje ulja i osnovne parametre kvalitete hladno prešanog ulja chie. Također je određena i oksidacijska stabilnost ulja, sa i bez dodanih antioksidanasa. Ispitivan je utjecaj pojedinog prirodnog antioksidansa na održivost hladno prešanog ulja chie. Primjenom standardnih metoda, određeni su parametri kvalitete ulja: peroksidni broj, udio slobodnih masnih kiselina, netopljive nečistoće, udio vlage u ulju. Antioksidansi korišteni u ovom istraživanju su: ekstrakt ružmarina (OxyLess®.CS), ekstrakt zelenog čaja, ekstrakt nara, ekstrakt maslinovog lista, eterična ulja origana, kadulje i rtanjskog čaja. Oksidacijska stabilnost ulja ispitana je primjenom Oven testa. Rezultati ispitivanja prikazani su kao vrijednost peroksidnog broja tijekom 4 dana trajanja testa. Najveće iskorištenje ulja kod prešanja sjemenke chie dobiveno je primjenom sljedećih procesnih parametara: nastavak za izlaz pogače 8 mm, brzina pužnice 35 Hz i temperatura glave preše 100°C. Od ispitivanih prirodnih antioksidanasa značajni antioksidacijski učinak pokazao je samo ekstrakt ružmarina OxyLess®.CS i ekstrakt zelenog čaja u udjelima 0,1 % i 0,3 %. Salvia hispanica L. ( chia ) is a plant of Labiatae family, whose seeds contain 25-35 % oil and have a high content of omega-3 linolenic fatty acid. The cold pressed chia oil was produced by pressing of chia seeds on a continued screw press, where three products are obtained: crude oil, oil sludge and cake. After the pressing, natural deposition of the produced crude oil and vacuum filtration was carried out. In this work, the influence of process parameters (temperature head presses, nozzle size and the screw speed - frequency) on oil yield and basic quality parameters of cold pressed chia oil was tested. The oxidation stability of oil was also examined, with and without added antioxidants. Influence of every individual natural antioxidant on the sustainability of the cold pressed chia oil was examined. With the application of standard methods, the oil quality parameters: peroxide number, free fat acids content, insoluble impurities, oil moisture content were determined. Antioxidants used in this research were as follows: rosemary extract (OxyLess®.CS), green tea extract, pomegranate extract, olive leaf extract, essential oils of oregano, sage and winter savory tea. The oxidation stability of oil was tested using the Oven test. Test results are shown as a peroxide number value over the 4 days duration of the test. The highest yield of chia oil was obtained by pressing at following process parameters: nozzle size 8 mm, frequency 35 Hz and the press head temperature 100°C. The most significant antioxidant effect shows only the rosemary extract OxyLess®.CS and the green tea extract in concentration of 0.1 % and 0.3 %.

U ovom radu istraživan je utjecaj procesnih parametara prešanja suncokreta na efikasnost proizvodnje hladno prešanog suncokretovog ulja te njegovu kvalitetu. Prešanje suncokretovih sjemenki provedeno je na labaratorijskoj pužnoj preši za proizvodnju hladno prešanih biljnih ulja. Prešanjem suncokreta dobivena su tri proizvoda: sirovo ulje, uljni talog i pogača. Prilikom prešanja mijenjali su se procesni parametri: temperature glave preše, brzina pužnice, te nastavak za izlaz pogače. Nakon prešanja provedeno je prirodno taloženje dobivenog sirovog ulja te centrifugiranje. Primjenom standardnih metoda određeni su parametri kvalitete ulja: peroksidni broj, slobodne masne kiseline, udio netopljivih nečistoća i udio vlage i hlapljivih tvari. Kako bi se odredila efikasnost proizvodnje ulja provedeno je ispitivanje udjela ulja u pogači metodom po Soxhlet-u. Primjenom veće temperature glave preše tijekom prešanja veće je iskorištenje ulja. Upotrebom nastavka manjeg promjera za izlazak pogače dolazi do porasta tlaka u preši, a time i do većeg iskorištenja sirovog ulja. Brzina pužnice tijekom prešanja utječe na iskorištenje ulja. In this study we have monitored the influence of process parameters on the efficiency of the pressing sunflower production of cold-pressed sunflower oil and its quality. Pressing sunflower seeds carried on labaratory screw press for producing cold pressed vegetable oils. Pressed sunflower produced three products: unpurified crude oil, oil sludge and cake of. While pressing we changed the process parameters: temperature head presses, frequency, and output cake thickness. After pressing conducted natural sedimentation and centrifugation on unpurified crude oil. Using standard methods we determined the parameters of quality: peroxide value, free fatty acids, the proportion of insoluble impurities and moisture and volatile matter. To determine the efficiency of production we conducted behind oil expeller method of Soxhlet. . Applying higher temperatures head presses for molding a greater yield of oil . Using the extension of a smaller diameter for the cake comes out to increase the pressure in the press , and thus a higher yield of the crude oil. Frequency during compression affects the yield of oil.

U ovom radu istraživan je utjecaj brzine rotora, vremena homogenizacije, vrste ugljikohidrata, mliječne komponente, žumanjka na reološka svojstva salatne majoneze. Za izradu majoneze korištene su različite vrste biljnih ulja: suncokretovo ulje, bučino ulje (hladno prešano) i rižino ulje. Mehanički proces homogenizacije majoneze proveden je kod 10 000 o/min i vremenu 3 min pri sobnoj temperaturi. Majoneze sa 65% uljnom fazom izrađene su po tradicionalnoj recepturi bez dodanog konzervansa čime je trajnost proizvoda vremenski ograničena. Mjerenja reoloških svojstava provedena su na rotacijskom viskozimetru s koncentričnim cilindrima pri temperaturama 25°C i 10°C. Iz dobivenih podataka izračunati su reološki parametri prividna viskoznost, koeficijent konzistencije i indeks tečenja. Dobiveni rezultati pokazuju da brzina rotora i vrijeme trajanja homogenizacije utječu na reološka svojstva salatne majoneze. Dodatak obranog mlijeka u prahu, glukoze i pasteriziranog žumanjka dovodi do veće viskoznosti majoneze. This paper shall research the influence of rotor speed, homogenisation time, types of sugar, types of milk components, types of eggs yolk on the rheological properties of mayonnaise. Different sorts of vegetable oils were used during the research: sunflower refined oil, pumpkin seed oil, cold-pressed rafined rice oil. The mechanical process of homogenisation of the mayonnaise has been done at 10,000 revolutions per minute for 3 minutes at room temperature. Mayonnaise with a 65% oil phase is made according to the traditional recipe without added conservatives, which limits its durability. The rheological measurements were performed on a rotating viscometer with concentric cylinders,at 25° C and 10°C. With the use of these results the rheological parameters - apparent viscosity,consistency coefficient and flow behaviour index - have been calculated. The results show that the rotor speed and the duration of homogenization affect the rheological properties of salad mayonnaise. Addition of skimmed milk powder, glucose and pasteurized egg yolks to the higher viscosity of mayonnaise.