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Colloidal stability of inkjet printing inks is one of the key parameters for their good printing performance. The stability of particles dispersed in water–based inks is usually achieved by electrostatic, steric, or electrosteric stabilization. Adsorption of polyelectrolytes of increased molecular weight at the solid interface of dispersed particles is responsible for electrosteric stabilization. In this work, stable homogeneous suspensions of MOx (TiO2 and ZnO) were prepared using gum arabic (GA) and solsperse 40000 as dispersants. GA is a natural polyanionic polysaccharide with carboxylic groups as anchors, while Solsperse 40000 is an anionic phosphated alkoxylated polymer of Lubrizol. Both dispersants provide electrosteric stabilization of pigments in water based inks. GA was employed as dispersant to study the effect on the surface properties of MOx nanoparticles. GA has been used as the stabilizing agent for ink pigments for a long time. It is well known that GA can make the MOx nanoparticles have good dispersibility and stability in GA colloidal solution for its low viscosity. The investigations on the optimum concentration of dispersants and the mechanism determining the dispersion behavior of MOx in aqueous dispersants solution were performed. Suspensions of MOx and GA/Solsperse were prepared first by dissolving dispersants in water. MOx were added in appropriate amounts. The weight ratio between MOx and GA (solsperse) was varied from 1/1 to 3.5/1. The ball milling was performed in a Retch PM 100 planetary ball mill at a constant milling speed of 250 rpm using YSZ jar and balls. The effects of different milling time (15, 30, 60, 90 and 180 min) on average particle sizes were investigated. Results show improved dispersion with a reduction of average particle sizes with increasing of milling time. Different ink formulations composed of MOx/dispersants (with the addition of 1, 2 propylene glycol and n-propanol) were prepared and their printability properties were tested using Inkjet printer Fuji Dimatix DMP-3000. The main goal of this work is to analyze the influences of different quantity of dispersants and milling conditions on the printing quality parameters of the ink using different substrates.

In this paper, zein nanoparticles were prepared by antisolvent precipitation of zein from aqueous ethanol solutions, in water. Influence of different parameters on preparation process and prepared nanoparticles was tested. Also, selfstanding films were casted from nanoparticle suspensions, with and without plasticizer. Thickness and surface roughness of different films was obtained.

In this work, films made of SF aqueous solution were prepared and characterized. SF was obtained from silkworm cocoons from which sericin was previously removed. In order to make films less brittle, plastisizer polyethylene glycol 200 (PEG 200) was added into aqueous solution of SF. SF films with added red cabbage dye were also made. Red cabbage dye is natural pigment used mainly as a food color. Anthocyanins are compounds that contribute to the color of this dye. The pH of red cabbage solution can affect both its color and intensity. In this work, the red cabbage dye was evaluated as a potential pH indicator that can be used for food packaging. The obtained films were characterized for FTIR analysis, water barrier and optical properties, solubility, and tested to color change on different concentrations of base, which imitates food spoilage.

The focus of this work was to prepare zein films by casting the aqueous dispersions of zein nanoparticles. Influence of ionic strength (10-2 M and 10-3 M NaCl) on stability of zein dispersions, and on optical properties, mechanical properties, water vapor permeability, moisture absorption, solubility in water of the casted zein films was investigated. Zein films were plasticized with either propylene glycol (PG) or polyethylene glycol 200 (PEG 200), and effects of plasticization were also studied.

Aim of this work was to investigate physico-chemical and mechanical properties of zein films casted from nanoparticle suspensions in water, with and without plasticizer, and compare it to zein films casted from aqueous ethanol solutions. In order to accomplish that, solubility, moisture absorption, water vapor permeability, tensile strength, elongation at brake, Young’s modulus and FTIR spectra of various zein films were determined.

Comparative analysis of different routes to prepare cutin nanoparticles was carried out.Nanoparticle properties, regardless of the preparation route, depend on the final pH of the solution and on the cutin isolation procedure. Influence of pH on cutin nanoparticle recovery, zeta potential and mean diameter is presented alongside with the influence of cutin solution concentration on cutin nanoparticle mean particle diameter.

In this work, a stable aqueous zein dispersion i.e. zein pseudolatex (latex - colloidal dispersion of polymer particles in a liquid) was prepared by spontaneous antisolvent precipitation of 10% w/w zein solution in 90% v/v aqueous ethanol. The prepared dispersion was concentrated in a rotary evaporator to a concentration of 4%. The method used for film preparation was by casting the zein dispersions in polystyrene dishes and vacuum-drying them at 60°C. During the film formation process several steps took place including water loss, deformation and coalescence of nanoparticles, resulting in homogenous film. Zein films prepared without a plasticizer are brittle, therefore zein films were plasticized with either propylene glycol (PG), glycerol (GLY), polyethylene glycol 200 (PEG 200) or polyethylene glycol 600 (PEG 600).

In this work, zein films were prepared by coalescing zein nanoparticles from aqueous zein dispersions i.e. zein latexes. Zein latexes were prepared by antisolvent precipitation, where 10% zein solution in 90% aqueous ethanol was drop–wise added to water to obtain dispersions of zein nanoparticles in water. The remaining ethanol was evaporated to obtain 4% m/m zein latexes. Thereafter, zein films were prepared by casting the latexes in silicone molds and air–drying at 50oC. The obtained films were characterized for morphology, surface roughness, water vapor permeability, opacity and color, and were benchmarked against zein films obtained by casting its aqueous ethanol solutions. Effect of plasticizer (30% propylene glycol on zein mass) on the film properties of the latex films was also investigated.

Biljni proteini, odnosno belančevine izolovane iz različitog biljnog materijala, poseduju odličan potencijal za primenu u proizvodnji, ali i pakovanju hrane. Oni poseduju različite funkcionalne osobine, kao što su sposobnost emulgovanja, stabilizovanja pene, geliranja, formiranja omotača i filmova itd., što im omogućava primenu u prehrambenoj i farmaceutskoj industriji. Zein je biljni protein, koji se može naći u žitaricama, a osnovni izvor ovog proteina je kukuruz (Zea mays). Zein nije rastvoran u vodi, a za njegovo rastvaranje najčešće se koristi razblaženi etanol. Smanjenjem koncentracije etanola u rastvoru zeina, bilo da se to postiže dodatkom nerastvarača ili uklanjanjem etanola (isparavanjem), zein može formirati različite koloidne strukture, koje pokazuju veliki potencijal za primenu u prehrambenoj industriji. Osobine ovih struktura zavise od načina pripreme, ali se na njih može uticati i dodatkom drugih materija u toku procesa pripreme. Stoga, osnovni cilj istraživanja u okviru ove disertacije bio je da se ispita mogućnost i uslovi formiranja nanočestica zeina i kompozitnih nanočestica zein/prirodna smola, kao i mogućnost primene takvih nanočestica za inkapsulaciju lipofilne aktivne supstance, odnosno za formiranje filmova zeina.Nanočestice (NČ) zeina (Z) i kompozitne nanočestice zein/šelak (Z/Š) i zein/kalafonijuim (Z/K) pripremane su metodom (ko)precipitacije usled smanjenja rastvorljivosti, gde su se etanolni rastvori makromolekula mešali sa vodom kao nerastvaračem. Ispitani su uslovi pripreme nanočestica zeina na njihove koloidne osobine. Pripremljene nanočestice karakterisane su primenom različitih metoda (dinamičko rasipanje svetla, elektroforetska pokretljivost, SEM). Takođe, ispitane su interakcije gume arabike (GA) sa Z i Z/K nanočesticama, upotrebom različitih tehnika, kao što su dinamičko rasipanje svetla i izotermalna mikrokalorimetrija. Ispitana je mogućnost inkapsulacije lipofilne aktivne supstance u Z i Z/K nanočesticama, primenom metode koprecipitacije usled smanjenja rastvorljivosti, na isti način kao što su pripremane same nanočestice. Filmovi zeina pripremani su izlivanjem disperzija nanočestica zeina i sušenjem na povišenoj tempreturi. Pripremljeni su filmovi iz disperzija sa nanočesticama različitog prosečnog prečnika ZDNČ90 i ZDNČ180 bez plastifikatora, kao i uz dodatak plastifikatora ZDPGNČ90 i ZDPGNČ180. U svrhu poređenja osobina filmova, pripremani su i filmovi iz rastvora zeina bez plastifikatora, ZR, i sa dodatkom plastifikatora, ZRPG filmovi. Ispitan je uticaj veličine čestica zeina kao i uticaj plastifikatora na morfologiju, barijerna i optička svojstva filmova (rastvorljivost, propustljivost vodene pare, boju, itd.).Utvrđeno je da se metodom precipitacije u nerastvaraču mogu dobiti zeinske i kompozitne nanočestice zein/smola. Na veličinu nanočestica može se uticati koncentracijom etanolnog rastvora biopolimera. Takođe, pH vrednost disperzije nanočestica utiče na njihov zeta potencijal, površinsku gustinu naelektrisanja, veličinu i stabilnost. Dodatak GA, u disperziju NČ utiče na zeta potencijal i veličinu nanočestica, odnosno nastalih aglomerata nanočestica. Mikrokalorimetrijskim merenjima utvrđeno je da su interakcije Z i Z/K nanočestica sa GA egzotermne, te da su najinteinzivnije na pH = 4. Merenja su pokazala da do zasićenja površine kod Z/K NČ dolazi pri masenom odnosu GA/NČ od 0,7. Kod Z NČ promena entalpije postaje konstantna nakon masenog odnosa GA/NČ 1. Takođe, utvrđeno je da se moguće pripremiti kontinualne zeinske filmove iz disperzija nanočestica, sušenjem na vazduhu. U poređenju sa filmovima dobijenim iz rastvora zeina, filmovi dobijeni iz disperzija su bili hrapaviji i krtiji. Takođe, hrapavost površine ZDNČ180 filmova bila je veća nego kod ZDNČ90 filmova. Dodatkom propilen–glikola kao plastifikatora smanjuje se krtost i hrapavost ZDNČ filmova. Svi ispitivani filmovi su, u ispitivanim uslovima, apsorbovali manje od 8% vlage, dok je rastvorljivost i Zr i Zd filmova u vodi bila je ispod 5%. Propustljivost vodene pare se nije značajno razlikovala (p < 0,05) za ZR, ZD i ZDPG filmove, nezavisno od veličinečestica. Optička zamućenost ZD filmova bila je veća nego kod ZR filmova, dok je najmanja bila kod ZDPG filmova, s obzirom da je dodatak plastifikatora uticao na smanjenje optičke zamućenosti. Pokazano je da udeo bele u boji filmova raste po redosledu ZR < ZRPG < ZDPG < ZD. Takođe je utvrđeno da žuta boja preovlađuje kod svih ispitivanih filmova. Statistička analiza pokazala je da ne postoji značajna razlika u mehaničkim svojstvima između filmova izlivenih iz disperzija nanočestica i filmova izlivenih iz etanolnog rastvora zeina., Plant proteins, i.e. proteins isolated from various plant materials, have excellent potential for use in food production, but also in food packaging. They possess various functional properties, such as emulsifying, foam stabilizing, gelling, coating, and film-forming properties, which allow them to be used in the food and pharmaceutical industries. Zein is a plant protein, which can be found in cereals, and the main source of this protein is corn (Zea mays). Zein is not soluble in water, and dilute ethanol is most often used to dissolve it. By reducing the concentration of ethanol in the zein solution, whether this is achieved by adding non–solvents or removing ethanol (evaporation), zein can form various colloidal structures, which show great potential for use in the food industry. The properties of these structures depend on the method of preparation, but they can also be influenced by the addition of other substances during the preparation process. Therefore, the main goal of the research within this dissertation was to examine the possibility and conditions of formation of zein nanoparticles and zein/natural resin composite nanoparticles, as well as the possibility of using such nanoparticles for encapsulation of lipophilic activesubstance, as well as for zein film formation.Zein (Z) nanoparticles and zein/shellac (Z/Š) and zein/rosin (Z/K) composite nanoparticles were prepared by the antisolvent (co)precipitation method, where ethanolic solutions of macromolecules were mixed with water as a non-solvent. The influence of the zein nanoparticles' preparation parameters on their colloidal properties was examined. Prepared nanoparticles were characterized by the application of different methods (dynamic light scattering, electrophoretic mobility, scanning electron microscopy). Also, interactions of gum arabic (GA) with Z and Z/K nanoparticles were investigated, using various techniques, such as dynamic light scattering and isothermal microcalorimetry. The possibility of encapsulation of lipophilic active substance in Z and Z/K nanoparticles was investigated, using the method of antisolvent coprecipitation in the same way as the nanoparticles themselves were prepared. Zein films were prepared by casting dispersions of zein nanoparticles and air drying. Films were prepared from dispersions with nanoparticles of different average diameters ZDNČ90 and ZDNČ180 without plasticizers, as well as with the addition of plasticizers ZDPGNČ90 and ZDPGNČ180. In order to compare their properties, films were also prepared from a solution of zein without a plasticizer, ZR, and with the addition of a plasticizer, ZRPG films. The influence of zein particle size, as well as the influence of plasticizers on morphology, barrier properties, and optical properties of films (solubility, water vapor permeability, color, etc.), were examined.It has been found that zein and composite zein/resin nanoparticles can be obtained by the antisolvent precipitation method. Nanoparticle size can be affected by the concentration of ethanol biopolymer solution. Also, the pH value of the dispersion of nanoparticles affects their zeta potential, surface charge density, size, and stability. The addition of GA to the dispersion of NP affects the zeta potential and size of nanoparticles, i.e. the formed agglomerates of nanoparticles. Microcalorimetric measurements showed that the interactions of Z and Z/K nanoparticles with GA are exothermic and that they are most intense at pH = 4. Measurements showed that surface saturation of Z/K NP occurs at a GA/NP mass ratio of 0.7. For Z NP, the change in enthalpy becomes constant after the mass ratio GA / NC 1. Also, it was found that it is possible to prepare continuous zein films from nanoparticle dispersions, by air drying. Compared with films obtained from zein solution, films obtained from dispersions were rougher and more brittle. Also, the surface roughness of ZDNČ180 films was higher than that of ZDNČ90 films. The addition of propylene–glycol as a plasticizer reduces the brittleness and roughness of ZDNČ films. All tested films, absorbed less than 8% of moisture, under the tested conditions, while the solubility of both Zr and Zd films in water was below 5%. Water vapor permeability did not differ significantly (p

Seme tikve (Cucurbita pepo) obiluje kako uljem tako i proteinima. Nakon izdvajanja ulja, proteini se koncentrišu u uljanoj pogači, sekundarnom proizvodu procesa proizvodnje ulja, gde njihov sadrţaj dostiţe do 65%. Proteini semena tikve su primamljiv sastojak za prehrambenu, farmaceutsku i kozmetičku industriju zbog svoje farmakološke aktivnosti i visoke biološke vrednosti. Pored toga, budući da su mnogi proizvodi ovih industrija po svojoj koloidnoj prirodi emulzije, proteini semena tikve bi se u njima mogli naći i kao prirodne površinski aktivne materije. Međutim, koloidna funkcionalnost proteina semena tikve se još uvek potcenjuje zbog globularne strukture za koju se vezuju slabija funkcionalna svojstva u odnosu na proteine sa fleksibilnijom strukturom. Prema tome, cilj ove disertacije je ispitivanje funkcionalnih osobina proteinskog izolata semena tikve, pre svega njegovih adsorpcionih i emulgujućih svojstava, kao i ispitivanje uticaja promene proteinske strukture putem enzimske hidrolize na ispitivana svojstva. Pripremljeni su izolat proteina semena tikve (IPST) i dva enzimska hidrolizata, H1 i H2. IPST, H1 i H2 su okarakterisani određivanjem sadržaja vlage, proteina i pepela, zatim, određivanjem prinosa, molekulske mase i zeta potencijala. Ispitan je uticaj koncentracije proteina/peptida (0,0001–1 g/100 cm3), pH (3–8) i jonske jačine (0–1 mol/dm3 NaCl) na rastvorljivost i adsorpciona svojstva: dinamički međupovršinski pritisak (ulje/voda), statički površinski (vazduh/voda) i međupovršinski (ulje/voda) pritisak, kinetiku adsorpcije i dilatacionu reologiju proteinskih adsorpcionih filmova. Nakon toga, ispitan je i uticaj pomenutih parametara na emulziona svojstva IPST, H1 i H2. Emulgujuća svojstva IPST, H1 i H2 su okarakterisana na osnovu prosečnog prečnika kapljica emulzija, raspodele veličina kapljica i stabilnosti emulzija. Utvrđeno je da je prinos IPST veći od prinosa oba hidrolizata za oko 65 %. IPST ima najniţu rastvorljivost na pH=5, što ujedno predstavlja i njegovu izoelektričnu tačku. Enzimskom hidrolizom IPST značajno se povećava rastvorljivost, posebno na pI=5. Povećanje jonske jačine je izazvalo salting–in ili salting–out efekat rastvorljivosti kod svih uzoraka u zavisnosti od pH. IPST, H1 i H2 poseduju površinsku aktivnost pri čemu je površinski/međupovršinski pritisak H1 i H2 manje zavistan od promene pH i jonske jačine u poređenju sa površinskim/međupovršinskim pritiskom IPST. Adsorpcijom na granicu faza IPST i oba hidrolizata obrazuju adsorpcione filmove sa dominantnom elastičnom komponentom. Emulgujuća svojstva IPST, H1 i H2 zavise od koncentracije uzorka, pH vrednosti i jonske jačine kontinualne faze. Pri koncentraciji od 1 g/100 cm3 i Ic=0 mol/dm3 pripremljene emulzije su stabilne na svim pH osim emulzije IPST na pH 5. Sve emulzije podležu gravitacionoj nestabilnosti. Pumpkin (Cucurbita pepo) seed is rich source of both, oil and proteins. Once the oil has been extracted, proteins concentrate in oil cake, a by–product of the oil extraction process, where their content can reach up to 65%. Pumpkin seed proteins are desirable ingredient in food, pharmaceutical and cosmetic industry due to their pharmacological activities and high biological value. Moreover, since many of products of these industries are, in colloidal terms, emulsions, pumpkin seed proteins could serve as surface active materies. However, colloidal functionality of pumpkin seed proteins is still underestimated for their globular structure which entails inferior functional properties to functional properties of proteins with more flexible structure. Based on that, the aim of this dissertation is to investigate functional properties of pumpkin seed protein isolate, adsorption and emulsifying properties, in the first place, and then to investigate the influence of modification of the protein structure, by means of enzymatic hydrolysis, on the aforementioned properties. Pumpkin seed protein isolate, IPST, and two enzymatic hydrolysates, H1 and H2, were prepared. IPST, H1 and H2 were characterized by determination of moisture, ash and protein content, then, by determination of protein recovery, molecular mass and zeta potential. Influence of the protein/peptide concentration (0.0001–1 g/100 cm3), pH (3–8) i ionic strength (0–1 mol/dm3 NaCl) on the solubility and adsorption properties: dynamic interfacial (oil/water) pressure, static surface (air/water) and interfacial (oil/water) pressure, adsorption kinetics and interfacial dilatational properties, was investigated next. In the end, influence of the aforementioned pharameters on the emulsifying properties of IPST, H1 and H2 was investigated. Emulsifying properties of IPST, H1 and H2 were discussed in terms of mean droplet diameter, droplet size distribution and emulsion stability. Protein recovery of IPST was determined to be 65 % higher than recovery of H1 and H2. Solubility of IPST was the lowest at pH 5, what presents the isoelectric point. The enzymatic hydrolysis of IPST significantly increased solubility, especialy at the isoelectric point. Increase in the ionic strenght led to salting–in or salting–out effect depending on pH of the sample. Three investigated samples, IPST, H1 and H2 exhibited surface activity, however, sufrace/interfacial pressure of H1 and H2 were found to be less influenced by change in pH or ionic strenght of the solution in comparison to the IPST. Once adsorbed to the interface IPST and both hydrolysates form interfacial film with dominant elastic component. Emulsifying properties of IPST, H1 and H2 depend on the concentration, pH and ionic strength of the continuous phase. Stabile emulsions were formed at concentration of 1 g/100 cm3 and Ic=0 mol/dm3 regardless of pH, with the exception of the IPST at pH 5. All emulsions were susceptibile to gravitational separation.

Mikrokapsulacija je tehnika kojom se nestabilne, međusobno inkompatibilne i biološki aktivne supstance prevode u stabilniji oblik, ili se omogućuje njihovo kontrolisano i ciljano oslobađanje. Osobine formiranih mikrokapsula, kinetika i mesto otpuštanja inkapsuliranih materija zavise, pre svega, od njihovog omotača. Savremene tendencije razvoja prehrambenih proizvoda i proizvoda farmaceutske i kozmetičke industrije, su sve više usmerene ka upotrebi prirodnih i biorazgradivih polimernih materija za formiranje omotača mikrokapsula. Cilj ove disertacije je mogućnost primene hitozana, netoksičnog, biorazgradivog derivata hitina, kao materije omotača mikrokapsula sa uljnim sadržajem. S obzirom na njegovu slabu površinsku aktivnost, istraživanja su usmerena na primenu interakcija hitozana sa suprotno naelektrisanim jonskim površinski aktivnim materijama (PAM) u vodenim rastvorima, kao mehanizmu za njegovo deponovanje na graničnoj površini ulje/voda. Primenom različitih metoda (tenziometrija, viskozimetrija, turbidimetrija, merenje elektroforetske pokretljivosti) interakcije hitozana sa natrijum-dodecil-sulfatom (SDS) i natrijum-lauriletar-sulfatom (SLES) su detaljno ispitane. Definisane su promene kako na granici faza, tako i unutar rastvora, a mehanizam formiranja kompleksa hitozan/PAM različitih osobina je u potpunosti razjašnjen. Utvrđeno je da do formiranja stabilnog koacervata dolazi pri masenom odnosu hitozan:SLES 1:2 i hitozan:SDS 1:2. Ispitivanje uticaja interakcije hitozan-PAM na osobine emulzionih sistema tipa ulje u vodi (veličina i raspodela veličina kapi, stabilnost) omogućilo je odabir hitozan-SLES sistema kao omotača pogodnog za dobijanje mikrokapsula uljnog sadržaja. Na osnovu ovih rezulatata kao uljna faza odabrani su trigliceridi srednje dužine ugljovodoničnih lanca (TSDL). Sušenjem emulzija primenom spray drying postupka dobijene se mikrokapsule uljnog sadržaja sa vitaminom E i ispitan je uticaj umreživača na njihove osobine. Karakterizacijom dobijenih mikrokapsula (određivanje sadržaja vlage, ispitivanje morfologije površine, efiksanost inkapsulacije vitamina E, kinetika otpuštanja vitamina E u in vitro uslovima) zaključeno je da na osobine mikrokapsula utiče vrsta i koncentracija umreživača. Mikrokapsule čiji omotač nije umrežen pokazale su najbolje karakteristike. Microencapsulation is a technique that unstable, incompatible and biologically active substances converted to a more stable form, or allow their controlled and targeted release. The properties of formed microcapsules, kinetics and the place of release of encapsulated substances, primarly depend on their shell characteristic. Modern trends in the development of food products and products of the pharmaceutical and cosmetic industries are increasingly focused on the use of natural and biodegradable polymeric materials for coatings. The aim of this dissertation is to investigate the possibility of using chitosan, non-toxic and biodegradable chitin derivative, as a shell material of microcapsules with oil content. Due to its low surface activity, the research is focused on the utilization of chitosan interactions with opositly charged ionic surfactants (sodium dodecyl sulfate (SDS) and sodium lauryl ether sulfate (SLES)) in aqueous solutions as mechanisms for its depositing at the oil/water interface. Based on detailed investigation of interactions in the chitosan-ionic surfactant systems using different methods (tensiometry, viscometry, turbidimetry, measurement of electrophoretic mobility), changes have been defined both at the interface and within the bulk, as well as the mechanism of formation of the coacervate phase. It has been determined that at chitosan:SLES and chitosan:SDS mass ratio of 1:2 stabile coacervate were formed. An investigation of the influence of interaction on the properties of oil-in-water emulsion systems (size and distribution of droplet size, stability) enabled the chitosan-SLES system to be selected as a shell suitable for obtaining microcapsules of the oil content. Also, based on these results, medium-chain triglycerides were selected as the oil phase of the emulsion. Microcapsules with vitamin E were obtained by spray drying of emulsions stabilized with chitosan/SLES complex. The influence of the crosslinker on the properties of microcapsules was investigated. Characterization of obtained microcapsules (moisture content determination, investigation of the surface morphology, efficiency of the vitamin E encapsulation, release in vitro kinetics of vitamin E) showed that type and concentration of crosslinking agents had influences the properties of microcapsules. Microcapsules without crosslinking agents have the most suitable characteristics.

Mikrokapsule, kao nosači aktivnih supstanci, imaju sve veću primenu u različitim granama industrije, naročito prehrambene i farmaceutske. Inkorporiranje biološki aktivnih supstanci unutar mikrokapsula omogućava maskiranje neprijatnih mirisa i ukusa, zaštitu osetljivih i lako isparljivih komponenata. Cilj ove doktorske disertacije je dobijanje mikrokapsula za istovremeno inkorporiranje hidrosolubilnih i liposolubilnih aktivnih materija, radi njihove zaštite i kontrolisanog otpuštanja. Mikrokapsule su formirane iz duplih emulzija tipa voda-ulje-voda (V/U/V) metodom koacervacije, odnosno deponovanjem koacervata, koji nastaje u sistemu dva suprotno naelektrisana proteina, želatina i natrijum kazeinata (NaKN), na granicu faza ulje/voda. Kao model supstance za hidrosolubilne i liposolubilne biološki aktivne materije, korišćeni su vitamini C i E. Najpre su detaljno ispitane interakcije u sistemu želatin/NaKN primenom različitih metoda (merenje zeta potencijala, tenziometrija, viskozimetrija, reološka ispitivanja). Na osnovu ovih rezultata definisane su promene, kako na granici faza, tako i unutar rastvora, kao i mehanizama formiranja koacervata između ova dva suprotno naelektrisana proteina. Utvrđeno je da se pri masenom odnosu želatin:NaKN od 2:1 dolazi do formiranja nerastvornog koacervata. Ispitan je uticaj interakcija u ovom sistemu na osobine duplih, V/U/V emulzija dobijenih emulgovanjem primarnih voda/ulje (V/U) emulzija u smeši želatin/NaKN, pri njihovim odabranim masenim odnosima i zaključeno je da interakcija između proteina u kontinualnoj fazi utiče na osobine emulzija. S obzirom da je prvi korak ka dobijanju stabilne V/U/V emulzije, dobijanje stabilne primarne V/U emulzije, ispitana je mogućnost primene lipofilnih emulgatora, poliglicerol poliricinoleata (PGPR) i poliglicerol estra jestivih masnih kiselina i njihovih smeša, za dobijanje 20% V/U emulzija. Ispitivanjem uticaja sastava smeše emulgatora i njegove koncentracije na formiranje adsorpcionog sloja na graničnoj površini ulje/voda i osobine formiranih V/U emulzija odabran je najpogodniji sistem za stabilizaciju primarnih emulzija. Nakon formulisanja stabilnih duplih V/U/V emulzija sa inkorporiranim vitaminima C i E, optimizovani su uslovi za dobijanje mikrokapsula umrežavanjem kompleksa proteina na kapima ulja pomoću genipina, a njihovo izdvajanje iz rastvora ostvareno je primenom Spray drying postupka. Karakterizacijom dobijenih mikrokapsula (ispitivanjem morfologije površine, efikasnosti inkapsulacije vitamina C i E, kinetike otpuštanja vitamina C u in vitro uslovima) zaključeno je da na osobine mikrokapsula utiče koncentracija umreživača, kao i interakcija između želatina i NaKN u kontinualnoj fazi emulzija V/U/V. Microcapsules, as active substance carriers, have increasing application in different industries, especially in food and pharmaceutical industry. Incorporation of the biologically active substances inside the microcapsules allows masking of unpleasant taste and smell, protection od sensitive and volatile components. The aim of this thesis is preparation of microcapsules for parallel incorporation of water and oil soluble active substances for their protection and controlled release. Microcapsules were formed from double water-oil-water emulsions (W/O/W) by coacervation method, depositing the coacervate formed in the system of two oppositely charged proteins, gelatin and sodium caseinate (NaCN), at the water/oil interface. As a model for water and oil soluble biological active substances, vitamins C and E were used. First of all, interactions in the gelatin/NaCN system were investigated in detail, by using different methods (measuring of zeta potential, tensiometry, vicometry, rheological investigations). Based on these results, changes at the interface and in the bulk of the system, as well as mechanisms of coacervate formation were defined. It has been determined that at gelatin:NaCN mass ratio of 2:1 non soluble coacervate were formed. Influence of the interactions in this system on properties of the W/O/W double emulsions, made by emulsification of primary water/oil (W/O) emulsions in gelatin/NaCN mixtures, at desired mass ratios of proteins, was investigated. It was concluded that interactions between proteins in continuous phase of emulsions have influence on their properties. As the first step in formation of stable W/O/W emulsions is obtaining stable primary W/O emulsion, possibility of using lipophilic emulsifiers, polyglycerol polyricinoleate (PGPR) and polyglycerol esters of edible fatty acids and their mixtures, for 20% W/O emulsions formation were investigated. Results of these investigations showed that composition of emulsifiers mixtures and their concentrations have an influence on adsorption layer, at the water/oil interface, formation, as well as on stability of W/O emulsion, and based on these results the most suitable system of emulsifiers were chosen. After formulation of stable double W/O/W emulsions with incorporated vitamins C and E, conditions for microcapsules formation, by crosslinking of proteins complex at oil droplets with genipin, were optimized, and for their separation from dispersion spray drying method was applied. Characterization of obtained microcapsules (investigation of the surface morphology, efficiency of the vitamins C and E encapsulation, release kinetics of vitamin C under in vitro conditions) showed that concentration of crosslinking agent, as well as interaction between gelatin and NaCN, have an influence on microcapsules properties.