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The objectives of this paper were to assess the economic potential of biodiesel production by new enzymatic transesterification, from refined sunflower oil with methanol, using Thermomyces lanuginosus lipase (TLL), enzyme covalently immobilized on SEPABEADS EC-EP/M support in micro-flow packed-bed reactors. Parameters for lab-scale immobilization, productivity and the amount of support packed inside a single packed-bed reactor were determined based on literature. Number of packed bed reactors were scaled up in order to reach the targeted biodiesel production of 10, 000 tonnes per year. Capital investment, operating costs and cash flow analysis carried out. Parametric sensitivity analysis (5 cases) were carried out to investigate the effect of certain key variables on plant costs. Lowest cost of production calculated to be 0.71 $/litre of biodiesel (Case 2). Cost of the carrier for enzyme immobilization is the key to commercial implementation of flow-intensified enzyme-based biodiesel production. The number of reuses of the enzyme affects productivity and profitability significantly.

The waste or by-product that remains after the extraction of oil from the seed is called meal or cake. Owing to its composition, these materials can have different biotechnological applications, such as production of enzymes (lipase, cellulase), antibiotics, mushrooms, vitamins, antioxidants, amino acids, organic acids, single-cell proteins, biologically active secondary metabolites, etc. In order to enlarge the current knowledge on different cold-press oil cakes composition, the present study aim to determine the composition of three different cold-press oil cakes: hull-less pumpkin (Cucurbita pepo L.), flax (Linum usitatissimum L.) and hemp (Canabis sativa L.). Contents of dry matter, ash, total and soluble proteins, ether extracts, neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), total organic carbon (TOC), total carbohydrates, simple sugars, total polyphenols and simple phenolic compounds were thoroughly analysed.

It is well known that the use of oil cakes as protein supplements, as flour, in human nutrition in combination with wheat or other flours, increases the nutritional value and has a positive effect on health, and even reduces the risk of some diseases. The objective of this study was to determine the chemical composition of three oil cakes: hull-less pumpkin (Cucurbita pepo L.), flax (Linum usitatissimum L.) and hemp (Canabis sativa L.) that remains after the production of cold-pressed of oil, before and after the treatment with two microorganisms (Trametes versicolor and Humicola grisea). The results showed that after the treatment, the amount of total nitrogen increased (from 247.69 to 500.55 g/kg db.), fat content decreased (from 365.53 to 24.40 g/kg db.), as well as the amount of soluble sugars (from 26.40 to 7.12 g/kg db.) for all three oil cakes. The results confirmed our hypothesis: after biological treatment, nutritional value of oil cakes was improved. The future prospective could be the use of biologically treated oil cakes as supplements in bakery products.

The aim of this study was to examine influence of three different concentrations of 2-mercaptoethanol, a well-known blocking reagent of non-occupied sites of Eupergit CM, on the activity of immobilized Thermomyces lanuginosus lipase (TLL). Enzyme immobilization on Eupergit CM was conducted in 1 M phosphate buffer pH = 7.5 for 24 hours at 25 °C, followed by filtration. Afterwards, blocking of non-occupied sites on Eupergit CM was performed with 0.2, 0.1 and 0.05 M 2-mercaptoethanol for 4 hours at 4 °C. Immobilization efficiency was monitored by determination of protein content and residual activity of lipase in filtrates, while activity retention by determination of Eupergit CM bound lipase activity. Results showed that immobilization of TLL on Eupergit CM during 24 hours, resulted with high immobilization efficiency. On average, 90.0 ± 1.5% of proteins and 98.5 ± 1.8% of lipase was found covalently bound on Eupergit CM. Blocking of non-occupied sites on Eupergit CM containing covalently bound TLL, by different concentrations of 2-mercaptoethanol caused significant reduction in lipase activity. Lipase activity retention was 13% for treatment with 0.2 M 2-mercaptoethanol, 30% for treatment with 0.1 M and 25% for treatment with 0.05 M 2-mercaptoethanol. This indicates that reduction in 2-mercaptoethanol concentration for non-occupied sites blocking of Eupergit CM, have beneficial effect on Thermomyces lanuginosus lipase activity retention. However, further investigation using blocking reagents such as glycine and aspartic acid, which does not have potential for disruption of disulphide bonds within enzyme structure, is on interest.

Lipases produces by fungi, yeasts and bacteria have found wide application in industrial scale production of fine chemicals. Besides, they have been found applicable for biodiesel synthesis. However, their use for industrial scale biodiesel production is still in the process of research. The main obstacle for industrial scale implementation is high cost of enzyme due to inability of reuse and/or enzyme stability. This can be improved by use of immobilized enzymes. Therefore, this research investigated immobilization of Thermomyces lanuginosus (TLL) lipase on solid support Eupergit CM. Covalent binding of TLL on Eupergit CM was performed in the presence of phosphate buffered saline (PBS ; pH = 7.5) at three different concentrations 0.01, 0.1 and 1 M, during 12 and 24 hours at 25°C. Immobilization efficiency was monitored by determination of protein concentration in filtrates remained after immobilization. The maximal enzyme retention on solid support, Eupergit CM, was achieved by use of 1M phosphate buffered saline after 24 hours, where 97% of proteins were found covalently bound on Eupergit CM, but significant amount of enzyme (92%) was also found after 12 hours of immobilization. Use of phosphate buffered saline of lower ionic strength resulted with significantly lower enzyme retention. Obtained results indicate importance of ionic strength for immobilization of Thermomyces lanuginosus lipase on Eupergit CM.

The aim of this paper was to determine the effect of sugar granulation on temperature profile of cookies. Each formulation for cookies differ with respect to used sugar granulation (1000 μm, 800 μm and 50 μm) and baking temperature (180 °C, 205 °C i 230 °C). The temperature was measured with thermocouples type T. The texture of cookies was analysed using the texture analyser, and the colour was determined using a Chroma Meter (Konica Minolta Chroma Meter, CR-400). After baking were measured changes in weight during baking, length, height and water content of cookies. Results of monitoring the temperature inside the cookies during baking showed that the cookies with smaller sugar granulation in formulation achieved the temperature of water evaporation faster. Results of analysis of texture showed that granulation of sugar do not affect significantly the parameters of strength and endurance. According to results of the total colour change, minimum value had cookies with addition of sugar granulation 800 μm and the largest had cookies with the addition of powdered sugar.

Mnogi uređaji za ekstrakciju pri svome radu troše značajne količine rashladne vode. Iz tog razloga javlja se potreba za racionalizacijom potrošnje rashladne vode. U ovome radu provedena je racionalizacija potrošnje rashladne vode u univerzalnom uređaju za ekstrakciju B-811 LSV. Studija potencijalne uštede rashladne vode napravljena je primjenom dimenzioniranog rashladnog tornja laboratorijskog mjerila. Za proračun rashladnog tornja određen je protok i temperatura rashladne vode na ulazu i izlazu iz hladila univerzalnog uređaja za ekstrakciju B-811 LSV, te temperaturu i relativnu vlažnost zraka u laboratoriju gdje su mjerenja provedena. Za mjerenje temperature rashladne vode korišteni su termoparovi tipa T. Na temelju izmjerenih parametara proveden je proračun rashladnog tornja. Proračunom rashladnog tornja utvrđena je potrebna visina (81,45 cm) i promjer baze rashladnog tornja (13,96 cm). Za potrebe provjere proračuna napravljene su dvije simulacije u programu CodeSkulptor. Rezultati dobiveni racionalizacijom potrošnje rashladne vode ukazuju na moguću uštedu u iznosu od 56,87 %. Many of the extraction devices use significant amount of cooling water to operate. Because of this very reason the need for rationalizing the cooling water consumption appeared. In this work, the rationalization of the cooling water consumption was conducted in the universal extraction unit B-811 LSV. The study of potential water savings was conducted by scaling a cooling tower to laboratory size. To calculate the dimensions of cooling tower it was necessary to determine the flow and the temperature of cooling water on inlet and outlet point of the condenser in the universal extraction unit B-811 LSV, also the temperature and relative humidity of laboratory air. For the measurement of cooling water temperature, the T-type thermocouples were used. The cooling tower dimensions were calculated by previously determined parameters. It was determined that the needed height and the base diameter of the cooling tower were 81.45 cm and 13.96 cm, respectively. For the verification of conducted calculations, two simulations were made in CodeSkulptor program. The results of scaling the cooling tower clearly indicate the possibility of lowering the cooling water consumption by 56.87%.

In recent years, there has been an increasing interest in degradation of lignocellulosic waste due to ecological problems caused by the large amount of such waste produced and its possible utilization as substrate for production of biofuels (renewable energy resources) and other bioproducts. In Slavonia region (Eastern Croatia), the most common raw materials used in food industry are soybean, rapeseed, corn, wheat and sugar beet. After their harvest, the remaining stems together with sugar beet leaves form “green waste” that contains high levels of cellulose, hemicellulose and lignin. Every year, more than 1.25 million tons of such waste is produced in Slavonia region. This “green waste” is mainly burned and it is not used further as a substrate for other industrial activities such as bioethanol/bioproducts production, so its potential remains untapped. A major challenge to full realization of the potential of lignocellulosic waste is to overcome its high degradation resistance (mostly due to the presence of lignin and hemicellulose that form a matrix surrounding cellulose – a glucose polymer) to become fermentable sugars. Since a number of microorganisms, mostly filamentous fungi, are able to degrade lignocellulosic components to various extents, biodegradation of these components could be a good strategy to overcome the above mentioned obstacle.

Cimetna i klorogenska kiselina polifenolni su spojevi koji su pronađeni voću, povrću, cvijeću i medu. Cilj je ovog rada bio odrediti UV/VIS svojstva cimetne i klorogenske kiseline u ovisnosti o primijenjenom pH. Snimanjem UV/VIS spektra cimetne i klorogenske kiseline u rasponu od 200 do 800 nm uočeno je kako obje kiseline pokazuju jedan vrh apsorbancije karakterističan za sve polifenole, a osim ovog vrha cimetna je kiselina pokazivala jedan dodatni vrh apsorbancije, a klorogenska kiselina čak tri dodatna vrha apsorbancije. Intenzitet i položaj, kao i pomak položaja vrhova specifičnih za pojedinu ispitanu kiselinu pokazali su se ovisnim o primjenjenom pH što je najvjerojatnije uzrokovano disocijacijom funkcionalnih skupina polifenola. Cinnamic and chlorogenic acid belongs to polyphenolic compounds found in fruit, vegetables, flowers and honey. The aim of this study was to determine pH dependence of cinnamic and chlorogenic acid UV/VIS properties. UV/VIS spectra recording from 200 to 800 nm revealed existence of one unique absorption peak characteristic for all polyphenols. Additionally, cinnamic acid showed existence of another peak characteristic for this polyphenol, and chlorogenic acid existence of three absorption peaks. Intensity and positions, as well as absorption peaks shift, showed dependence on pH applied, what can be attributed to dissociation of functional groups.

Cimetna i klorogenska kiselina polifenolni su spojevi koji su pronađeni voću, povrću, cvijeću i medu. Cilj je ovog rada bio odrediti UV/VIS svojstva cimetne i klorogenske kiseline u ovisnosti o primijenjenom pH. Snimanjem UV/VIS spektra cimetne i klorogenske kiseline u rasponu od 200 do 800 nm uočeno je kako obje kiseline pokazuju jedan vrh apsorbancije karakterističan za sve polifenole, a osim ovog vrha cimetna je kiselina pokazivala jedan dodatni vrh apsorbancije, a klorogenska kiselina čak tri dodatna vrha apsorbancije. Intenzitet i položaj, kao i pomak položaja vrhova specifičnih za pojedinu ispitanu kiselinu pokazali su se ovisnim o primjenjenom pH što je najvjerojatnije uzrokovano disocijacijom funkcionalnih skupina polifenola.

Otpad, odnosno nusproizvod koji zaostaje nakon hladnog prešanja uljarica naziva se pogača. Obzirom da sadrže zaostalo ulje, velike količine proteina, prehrambenih vlakana, minerale i druge bioaktivne spojeve, pogače su prepoznate kao vrijedna sirovina u proizvodnji visokovrijednih proizvoda ili kao hranjiv dodatak prehrani. U ovom radu provedena je kemijska analiza pogače buče i lana, prije i nakon biološke obrade u uvjetima uzgoja na čvrstim nosačima s gljivom bijelog truljenja, Trametes versicolor, i termofilnom gljivom, Humicola grisea. Udjeli suhe tvari, pepela, ukupnih i ekstraktibilnih proteina, masti, vlakana (NDF, ADF, ADL), ekstraktibilnih šećera, te ukupnog organskog ugljika određeni su u neobrađenim pogačama, te nakon 10 dana biološke obrade. Maseni udjeli pojedinačnih šećera su analizirani svakog dana uzgoja. Na temelju dobivenih rezultata zaključeno je da se prilikom obrade bučine pogače s Trametes versicolor značajno smanjuje udio masti i vlakana, dok prilikom obrade s Humicola grisea ne dolazi do tolike promjene u navedenim udjelima, ali se primjeduje porast udjela proteina. Kod obrade pogače lana s oba mikroorganizma, zabilježen je porast udjela proteina i ekstraktibilnih šećera, dok je udio vlakana i masti smanjen. Na temelju analize pojedinačnih šećera ustanovljeno je kako oba mikroorganizma imaju sposobnost razgradnje polisaharida, uz oslobađanje monosaharida i oligosaharida. The waste, or by-product that remains after the cold pressing of the oilseeds, is called oil cake. Due to the residual oil content, high amount of proteins, dietary fibers, minerals and other bioactive compounds, oil cakes are recognized as a valuable raw material in the production of high-value products, or as a nutritional dietary supplement. In this paper, pumpkin and flaxseed oil cakes were analysed, before and after fermentation with white rot fungus, Trametes versicolor, and thermophilic fungus, Humicola grisea, using solid state technology. Contents of dry matter, ash, total and extractable proteins, ether extract, fibers (NDF, ADF, ADL), extractable sugars, and total organic carbon were determined in untreated oil cakes and after 10 days of fermentation. Concentration of simple sugars was analyzed every day of cultivation. Based on the obtained results, it was concluded that after processing pumpkin oil cake with Trametes versicolor, contents of ether extract and fibers are significantly reduced, while processing with Humicola grisea does not have significant impact on those parameters, but causes an increase in protein content. After processing of flaxseed oil cake with either of the two microorganisms, an increase in the protein and extractable sugars content was observed, while contents of fibers and ether extract decreased. Based on the analysis of individual simple sugars, it was found that both microorganisms have the ability to break down polysaccharides, simultaneously releasing monosaccharides and oligosaccharides.

Na Prehrambeno-tehnološkom fakultetu Osijek (PTFOS) se kao energent koristi voda za piće u rashladne svrhe jer ne postoji sustav rashladne vode. Voda za piće kao rashladna voda se koristi u laboratorijima za znanstveno-istraživački rad i nastavni rad (studentske vježbe). Na temelju analize potrošnje rashladne vode s ciljem uštede i ekološkog pristupa potrošnji vode, te smanjenja izdataka za vodu, u okviru ovog diplomskog rada izrađen je model rashladnog tornja. Za vrijeme provođenja vježbe Određivanje masti po Soxhletu u trajanju od 240 min potrošeno je rashladne vode 243,69 L. Provođenjem vježbe Određivanje masti po Soxhletu uz hlađenje rashladne vode u konstruiranom modelu rashladnog tornja za istu vježbu utrošeno je 5,33 L što je za 97,81 % manje u odnosu na provođenje vježbe bez hlađenja rashladne vode u rashladnom tornju. Od ukupno potrošene količine vode na godišnjoj razini za koju se drži da je potrošena u rashladne svrhe na PTFOS-u u znanstveno-istraživačke i nastavne svrhe, (1.241,5 m3) moguće je primjenom konstruiranog modela rashladnog tornja uštedjeti najmanje 87,5 % (1.086,1 m3) što iznosi 15.898,5 kn/god. At the Faculty of Food Technology Osijek (PTFOS) drinkable water is used in the cooling purposes because there is no cooling water system at the institution. Drinking water as cooling water is used in laboratories for scientific research and teaching activities (student exercise). Based on the analysis of the consumption of cooling water with the aim of saving and ecological approach to water consumption and reduction of expenditures for water, in the context of this diploma thesis the model of cooling tower was made. While conducting exercises Determination of fat by Soxhlet for a period of 240 minutes 243.69 L was spent. Conducting the exercise Determination of fat by Soxhlet using water cooled down in the model of cooling tower the 5.33 L od cooling water was spent for whole excercise, which is 97.81% less than conducting exercise without cooling the cooling water in the cooling tower. Of the total amount of water consumed on an annual basis which is considered to be consumed in cooling purposes at PTFOS-in for scientific and teaching activities (1,241.5 m3), using the constructed model of the cooling tower, can save at least 87.5% (1086.1 m3) which amounts to 15,898.5 kn/year.