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Cilj ovog diplomskog rada bio je ispitati utjecaj vremena miješanja na svojstva tamnih i mliječnih čokolada. Za proizvodnju čokolada korišten je laboratorijski kuglični mlin uz primjenu sljedećih uvjeta: temperatura kupelji 55 °C; 2,5 kg kuglica za tamnu čokoladu, 3 kg kuglica za mliječnu čokoladu; brzina miješanja60 o/min. Čokolade su proizvedene u kugličnom mlinu s vremenima miješanja od 3, 4 i 5 h te nakon temperiranja, upločavanja i hlađenja na 8 °C određeni su sljedeći parametri: boja (odmah nakon hlađenja, nakon 24 h, nakon 48 h i nakon tjedan dana), tekstura, veličina čestica i viskoznost. Rezultati su pokazali da je ukupna promjena boje veća kod tamnih čokolada u odnosu na mliječne čokolade. Tvrdoća kod tamnih čokolada je najmanja u uzorku koji se miješao 4 h, dok uzorak s istim vremenom miješanja kod mliječnih čokolada ima najveću tvrdoću. Najveće smanjenje čestica kod tamnih i mliječnih čokolada primijećeno je kod uzoraka koji su se najduže miješali. Povećanjem vremena miješanja došlo je i do povećanja vrijednosti Casson – ove plastične viskoznosti, a u usporedbi s tamnim čokoladama veću granicu tečenja imaju uzorci mliječnih čokolada. The aim of this study was to investigate the effect of mixing time on the properties of dark and milk chocolates. For production of chocolate laboratory ball mill was used under the following conditions: bath temperature 55 °C, 2.5 kilograms of balls for dark chocolate, 3 kilograms of balls for milk chocolate; speed of mixing 60 rpm. Chocolates were produced with mixing times of 3, 4 and 5 hours and after tempering, moulding and cooling at 8 °C the following parameters were determined: colour (after cooling, after 24 hours, after 48 hours and after one week), texture, particle size and viscosity. The results showed that the total colour change was greater for dark chocolates compared to milk chocolates. Hardness for dark chocolates was lowest in the sample that was mixed for 4 hours, while milk chocolate with the same mixing time had the highest hardness. The largest decrease of particles in both dark and milk chocolates was observed in the samples that were mixed the longest time. Increasing the mixing time also led to an increase in the value for Casson plastic viscosity and, compared to dark chocolates, milk chocolate samples had a higher yield stress.

Cilj ovog diplomskog rada je odrediti kako duljina trajanja miješanja obroka (TMR) u mikser prikolici utječe na ujednačenost miješanja i udio pojedinih čestica . Istraživanje je provedeno na gospodarstvu na izmješanom krmivu kojim se hrani 170 grla simentalske tovne junadi i junica. Sijeno livadno, sjenaža lucerne, silaža kukuruza, visoko vlažno zrno kukuruza i dopunska krmna smjesa su miješani 45 i 90 minuta u mikser prikolici (5m3) Sano Profi Mini i istovareni na hranidbeni stol. Uzorci obroka su uzimani sa početka, sredine i kraja hranidbenog stola svakodnevno tijekom dva tjedna. U prosušenim zorcima obroka prosijavanjem na Penn State Particle Seperator sitima veličine 19 mm, 8 mm i 1.18 mm određena je veličina čestica, a koncetracija natrija je bila pokazatelj iziješanosti obroka. U uzorcima je određen udjel suhe tvari, natrija, sirovih proteina i neutralnih deterdžent vlakana. Miješanje obroka 90 i 45 minuta dobije se odlična izmješanost (< 5%) obroka mjerena koncetracijom natrija u suhoj tvari. Miješanje u trajanju 90 min daje manje dnevne varijacije. Miješanje i usitnjavanje hrane tijekom 90 minuta i 45 minuta rezultira prosječnom veličinom koja osigurava više od minimalno potrebne količine efektivnih valakan za održavanje normalne kiselost buraga. Međutim, miješanje od 90 minuta daje ujednačeniju raspodjelu veličina vlakana tijekom tjedan dana mjerenja što osigurava ravnomjernu količinu svake frakcije vlakana junadi u svakom boksu cijekom cijelog tova. Zaključno, suhe obroke u maloj mikser prikolici bolje je miješati 90 nego 45 minuta. The aim of this master thesis was to assess the effect length of a mixing time of total mixed ration (TMR) for beef on its uniformity and distribution of particle size. Research was conducted on a small family farm on 170 Simental bulls and heifers fed with the same ration composed of meadow and alfalfa hay, corn silage, high moisture corn and complementary feed mixed with maize. One-week all cattle fed with TMR mixed for 90 min and another week with the same TMR mixed 45 min in small (5m3) TMR Sano Profi Mini mixer. The sodium content in dry matter used as an indicator of the consistency of total mixed ration and particles size distribution of TMR were determined using Pen State Particles Separator with three size holes size 19 mm, 8 mm, and 1.18 mm. Uniformity from TMR mixing 90 and 45 min measured by coefficient of variation was excellent (< 5%), but 90 min mixing time obtained lower day to day variation. Particle size distribution was generally according the standard for both times. Geometric means of particle length for both mixing times were 4.38 mm and 4.82 mm and assured adequate amount of effective neutral detergent fibre for beef. Ration mixed longer time had less long fibre and more middle (1.18 – 8 mm) particle size and that indicate better cutting of forages. But, mixing 90 min resulted with more consistent uniformity among the day of investigation. These result of the investigation indicate that 90 min mixing in small mixer improved consistency of TMR over time and uniformity under and between of particle size fractions.

Kvaliteta plodova masline, postupak prerade, te vrijeme i način skladištenja maslinovog ulja samo su neki od čimbenika koji direktno utječu na njegovu kvalitetu. Svaki korak u preradi plodova masline u ulje izrazito je važan i direktno utječe na samu kvalitetu i svojstva maslinovog ulja, međutim miješanje maslinovog tijesta možemo izdvojiti kao najbitniji korak prerade plodova u ulje. Vrlo je važno da se tijekom procesa prerade očuva kemijski sastav maslinovog ulja. Brojni su pokazatelji kvalitete maslinovog ulja, ali jedan od značajnijih je njegova oksidacijska stabilnost. Određivanjem oksidacijske stabilnosti možemo odrediti optimalne uvjete pri procesu prerade plodova u ulje. Oksidacijska stabilnost ulja direktno ovisi o temperaturi i vremenu miješanja maslinovog tijesta, te o načinu i vremenskom periodu skladištenja ulja. U ovom radu ispitivan je utjecaj temperature, vremena miješanja i vremena skladištenja na kvalitetu maslinovog ulja dobivenog iz plodova masline sorte levantinka. Određivana je oksidacijska stabilnost uzorka maslinovog ulja dobivenog iz plodova maslina ubranih 2013. godine. Ispitivanjem se pokazalo da je najveću oksidacijsku stabilnost imalo ulje dobiveno pri temperaturi 36°C i vremenu miješanja od 60 minuta. Uočeno je da povećanjem temperature miješanja iznad 36°C i produljenim vremenom skladištenja vrijednost oksidacijske stabilnosti maslinovog ulja opada. The quality of the olives, the way of processing, and the time and method of storing the oil are just some of the factors that directly affect its quality. Every step in the procedure of processing olive oil is extremely important and directly affects the quality and taste of olive oil, but mixing of the olive dough can be described as the most important step in the process from oilseed to oil. It is very important that the chemical composition of olive oil is maintained during the processing process. There are numerous indicators of olive oil quality, but one of the most significant is its oxidation stability. By determining oxidation stability, we can determine optimal conditions for processing oilseeds to oil. The oxidation stability of the oil directly depends on the temperature and the time of mixing the olive dough, as well as on the condition and storage time of the oil. In this study the influence of temperature, mixing time and storage time on the quality of the oil obtained from levantine varieties was investigated. The oxidation stability was examined on samples of olive oil obtained from the harvest in 2013. The highest oxidation stability showed the oil obtained at a mixing temperature of 36°C, and a mixing time of 60 minutes. Also, the mixing temperature increase above 36 °C and extension of storage time decreases oxidation stability of the olive oil.

Maslinova ulja se kategoriziraju ovisno o njihovoj kvaliteti. Na konačnu kvalitetu maslinovog ulja utječe više faktora kao što su kvaliteta plodova masline, postupak prerade i način čuvanja dobivenog ulja. U procesu prerade posebnu pozornost treba obratiti na postupak miješanja maslinova tijesta. Tijekom miješanja moguć je gubitak polifenola, što će u konačnici utjecati na kvalitetu maslinovog ulja i njegovu daljnju zaštitu od oksidacije. Nakon prerade dobiveno ulje se čuva u svježem i prozračnom prostoru pri konstantnoj temperaturi u posebnim spremnicima zaštićeno od kontakta s kisikom. Poznavanje oksidacijske stabilnosti ili održivosti ulja važno je kako bi se unaprijed moglo odrediti vrijeme za koje se ulje može sačuvati od jače izražene oksidacije, bez bitnih promjena kvalitete, naročito senzorskih svojstava. U ovom radu ispitivan je utjecaj temperature, vremena miješanja i vremena skladištenja na kvalitetu maslinovog ulja dobivenog iz plodova maslina sorte Oblica. Ispitivanja su pokazala da je najveću oksidacijsku stabilnost imalo maslinovo ulje dobiveno pri temperaturi miješanja 36 ℃ . Vrijeme miješanja nije imalo značajniji utjecaj na oksidacijsku stabilnost ulja. Olive oils are categorized depending on their quality. The quality of olive oil ultimately is being determined by several factors, such as the quality of olives, procedure of processing and the way oil is being stored. In the processing procedure, special attention should be given to the process of olive doughs mixing. During the process of mixing, there is a possibility of polyphenols degradetion, which will ultimately affect the quality of olive oil and its further resistance to oxidation. After processing, obtained oil is kept in fresh and airy environment at a constant temperature in the special containers without contact with oxygen. Knowing the oxidation stability and sustainability of oil is important in order to predict for how long the oil can be preserved from stronger expressed oxidation without any significant changes in its quality, particularly sensory properties. In this paper the influence of temperature, mixing time and storage time on the quality of olive oil obtained from the Oblica olive variety was examined. The study revealed that the highest oxidation stability showed the olive oil obtained by mixing at temperatire of 36 ℃ . The mixing time had no significant effect on the oxidation stability of oil.