Neki problemi proizvodnje i prerade ovčjeg mlijeka

Brdsko planinski tereni predstavljaju oko 65 % ukupne površine Jugoslavije, a znatan dio naročito planinskih predjela, može se potpunije iskoristiti jedino odgajanjem ovaca

Preservation of meat and meat products using nanoencapsulated thyme and oregano essential oils

Among other plants, thyme and oregano are commonly used in Mediterranean cuisine, especially in meat dishes. Although the essential oils of these two plants possess great antimicrobial and antioxidative properties, their application as natural meat preservatives are limited due to hydrophobicity, sensitivity to external factors and interaction with food components. Furthermore, essential oils can have adverse impacts on meats organoleptic properties. A possible way to overcome these barriers is by incorporating essential oils into nanometric delivery systems. Nano-sizing essential oils increases their stability, protects them, and allows their controlled release. This enhances the bioavailability of the essential oils and reduces their possible adverse impact on meat products organoleptic properties by preventing their unwanted interactions with food components. The antibacterial and antioxidative effect of nanoencapsulated essential oils is confirmed in numerous studies, and some of them show that in this form, essential oils were potent in food models e.g. beef burgers, pate and rainbow trout. However, a more promising way to introduce nano forms of essential oils into foods is incorporating them in packaging systems

Some Types of Introductory Formulas in Greek Klephtic (Heroic) Epic

Certain types of introductory formulas typical of klephtic epic songs are synoptically demonstrated and analyzed. The introduction outlines the historical development of this category of folk songs, based on occasionally opposing views of literary historians and scholars concerned with the study of Greek folklore. The analysis, performed on a selected corpus of Greek klephtic epic songs, reveals basic structural principles that the anonymous folk singer abided by whilst composing these songs

Effect of dietary supplementation with medium chain fatty acids on growth performance, intestinal histomorphology, lipid profile and intestinal microflora of broiler chickens

The aim of the present study was to assess the effects of medium-chain fatty acid (MCFA) diet supplementation on growth performance, intestinal histomorphology, serum biochemistry and intestinal microflora of broiler chickens. The study was performed on 180 one-day-old broilers of the same origin (Cobb 500 hybrid), over a 42-day period. They were fed diets supplemented with three treatments: control group (basal diet without supplementation); group with MCFA supplementation; and group with MCFA and coccidiostat supplementation. Broiler chickens fed diets supplemented with MCFAs had a significantly greater final bodyweight. The weights of carcass cuts (breast, drumsticks with thighs and wings) were greater in broilers receiving MCFAs than in control broilers. The addition of MCFAs to broiler diet significantly increased villus length and crypt depth in the duodenum and caecum, and significantly decreased villus width in the duodenum and ileum. Additionally, serum HDL-cholesterol and triglyceride concentrations were increased significantly in broilers with MCFA dietary supplementation. The results indicated that the MCFA diet supplementation had a beneficial effect on the performance of broiler chickens, their intestinal histomorphology and microflora.Keywords: Carcass characteristics, coccidiostat supplementation, nutrition, poultry, serum biochemistr

Potreba i efekti dinamičkih sustava za detekciju defekata točkova željezničkih vozila

State of railway vehicles highly influences transport safety due to vehicle derailments and in the same time worsens the quality of freight and passenger transportation. One of important elements that influence the state of railway vehicles is the wheel state. Wheel defects are common in railway transport. Therefore, timely defect detection is very important. This paper presents ways and effects of timely detection of wheel defects.Stanje željezničkih vozila bitno utječe na sigurnost prometa zbog rizika iskliznuća i istovremeno smanjuje kvalitet prevoza robe i putnika. Jedan od bitnijih čimbenika koji utječu na stanje željezničkih vozila jeste stanje točkova. Defekti točkova su česta pojava u željezničkom prometu. Iz tog razloga, veoma bitno je pravovremeno otkrivanje defekata. U ovom radu su prezentirani načini i učinci pravovremenog detektiranja defekata točkova

Improving the packaging performance of low-density polyethylene with modified nanocellulose barrier layers

U okviru ove doktorske disertacije izvršeno je formiranje polietilenskih/polikaprolaktonskih (PE/PCL) hibridnih materijala na bazi nanoceluloze i metalnih oksida. Rad je podeljen na četiri celine. U prvoj je sintetisana i okarakterisana nanoceluloza NC i modifikovana nanoceluloza NCMA i formirani su kompoziti na bazi gvožđe oksida NC-Fe3O4 i NCMA-Fe3O4. U drugom delu su formirani i ispitani dvoslojni hibridni filmovi PE/PCL sa kompozitima NC-Fe3O4 i NCMA-Fe3O4 u polikaprolaktonskom sloju. U trećem delu je sintetisana i okarakterisana nanoceluloza NC i modifikovana nanoceluloza NCMA i formirani su kompoziti na bazi bakar (II) oksida NC-CuO i NCMA-CuO i u četvrtom su formirani i ispitani dvoslojni hibridni filmovi PE/PCL sa kompozitima NC-CuO i NCMA-CuO u polikaprolaktonskom sloju. U prvom delu disertacije su sintetisani kompoziti nanoceluloza-magnetit (NC-Fe3O4) i maleinskom kiselinom funkcionalizovana nanoceluloza/magnetit (NCMA-Fe3O4), a zatim upotrebljeni kao punioci u polikaprolaktonskom sloju (PLC) pri različitim koncentracijama (5, 10 i 15 mas%). Kompozitnim materijalima nanoceluloza-magnetit su najpre proučavane strukturne, morfološke i termalne karakteristike, a nakon toga su inkorporirani u PCL sloj. Strukturna analiza izvršena je na osnovu rezultata dobijenih primenom rendgenske difrakcione analize (XRD) i infracrvene spektroskopije sa Furijeovom transformacijom (FTIR). Morfološka svojstva su proučavana skenirajućom elektronskom mikroskopijom (SEM). Termička svojstva su ispitana primenom termogravimetrijske analize. U drugom delu disertacije, polikaprolaktonski sloj sa puniocima je nanet na površinu polietilenske folije i ispitana su barijerna svojstva dobijenih hibridnih dvoslojnih filmova. Dodatak filera (punilaca) ne narušava prvobitna svojstva polimernog sloja, naročito u pogledu njegovih barijernih svojstava...Synthesis and characterization of polyethylene/polycaprolactone-modified nanocellulose hybrid materials containing different metal oxides was performed. The work is divided into four parts, and the first is a synthesized and characterized NC nanocellulose and modified NCMA nanocellulose, and composites based on iron oxide NC-Fe3O4 and NCMA- Fe3O4 are formed. In the second part, two-layer hybrid PE/PCL films were formed and tested with NC- Fe3O4 and NCMA- Fe3O4 composites in a polycaprolactone layer. In the third part, NC nanocellulose NC and modified NCMA nanocellulose were synthesized and characterized by copper (II) oxide NC-CuO and NCMA-CuO composites, and in the fourth, two-layer hybrid PE/PCL films were formed with NC-CuO and NCMA-CuO in a polycrystalline layer. Nanonocelulose/magnetite (NC-Fe3O4) nanocomposite and maleic acid functionalized NC/magnetite (NCMA-Fe3O4) nanocomposite were prepared and used as filler at various concentrations (5, 10 and 15 wt. %) in polycaprolactone (PCL) layer. The structural, morphological and thermal properties were investigated, upon composite materials were incorporated in PCL layer. Structural properties of composites were investigated by using FT–IR (Fourier transform infrared spectroscopy) and XRD analysis. The morphological properties were investigated by SEM (scanning electron microscopy). The second part of the thesis was focused on characterization of hybrid multicomponent films containing Fe3O4 nanoparticles. Polycaprolactone filled with nanocellulose/magnetite composites were coated on LDPE layer and barrier properties of low-density polyethylene/polycaprolactone-modified nanocellulose hybrid materials were investigated..

Necessity and effects of dynamic systems for railway wheel defect detection

State of railway vehicles highly influences transport safety due to vehicle derailments and in the same time worsens the quality of freight and passenger transportation. One of important elements that influence the state of railway vehicles is the wheel state. Wheel defects are common in railway transport. Therefore, timely defect detection is very important. This paper presents ways and effects of timely detection of wheel defects

CHEMICAL EVALUATION OF AUTOCHTHONOUS VARIETY 'PROKUPAC' RED WINE WITH THE ADDITION OF SELECTED AROMATIC HERBS

The quality parameters and chemical composition (total phenolics, total flavonoids and total anthocyanins) of the red wine obtained from the autochthonous variety 'Prokupac' (Vitis vinifera L.) with the addition of the selected aromatic herbs (Pimpinella anisum L., Cinnamomum zeylanicum, Artemisia absinthium and Glycyrrhiza glabra) were examined in two consequtive vintages (2013-2014). The differences in contents of total extract, reducing sugars and ash between the studied samples were observed, but with no statistical significance between both examined years and analyzed wines. 'Prokupac' red wines with the addition of aromatic herbs stood out with significantly higher contents of total phenolics (371.4-594.3 mg GAE L-1) and total flavonoids (136.2-243.2 mg CTE L-1) while lower total anthocyanins content was noticed, when compared to 'Prokupac' red wine used as control (p<0.05). The unfavourable weather conditions in the vintages 2013 and 2014, reflected notably on the quality of the obtained wine. To analyze the correlations between wine quality parameters and the similarity of individual wine samples, Principal Component Analysis (PCA) was used

Unapređenje vijabilnosti i stabilnosti probiotskog proizvoda sa Saccharomyces boulardii DBVPG

In recent decades, probiotic products have been increasingly used to prevent certain gastrointestinal and urogenital disorders, to improve the general condition of the body and as a supplement to pharmacological therapy. They are most often registered as dietary supplements, and less often as drugs in the form of capsules, powders, and solutions. Optimization of technological processes of production and packaging of these products aims to maintain probiotic characteristics while adhering to all criteria during production that ensure quality, bioavailability and optimal therapeutic effects. In this paper, the importance of choosing primary and secondary packaging materials was explored with the aim of preserving the viability of probiotic cells in capsules for two years, i.e. during the shelf life. By comparing the applications of polyvinyl chloride (PVC) and PVC/polyvinylidene chloride/polyethylene blister foils, better protection of probiotic cells was observed by applying the multilayer foil. In addition, in this research, further improvements of probiotic cell protection were achieved by applying a secondary packing-flow pack bag with inert gas for storing multilayered blisters.Probiotski proizvodi se poslednjih decenija sve više koriste za prevenciju određenih gastrointestinalnih i urogenitalnih poremećaja, za poboljšanje opšteg stanja organi-zma i kao dopuna farmakološke terapije. Najčešće su registrovani kao dijetetski suple-menti, a ređe kao lekovi u obliku kapsula, praškova i rastvora. Optimizacija tehnoloških procesa proizvodnje i pakovanje ovih proizvoda ima za cilj održavanje probiotskih karakteristika uz istovremeno pridržavanje svih kriterijuma u toku proizvodnje koji osiguravaju kvalitet, biološku raspoloživost i optimalno terapijsko dejstvo U ovom radu razmatran je značaj izbora primarnog i sekundarnog materijala za pakovanje sa ciljem očuvanja vijabilnost probiotskih ćelija u kapsulama tokom dve godine tj. tokom roka upotrebe. Poređenjem primene PVC (polivinil hlorid) i PVC/poliviniliden hlorid/poli-etilen (PVC/PVdC/PE) blister folija uočena je bolja zaštita probotskih ćelija od kiseonika i vlage primenom višeslojene folije. Dodatne efekte zaštite probiotskih ćelija u ovom radu potvrdjene su primenom dodatne zaštite blistera upotrebom sekundarnog pakovanja (engl. flow pack) kesice sa inertni gasom

Multielement determination using inductively coupled plasma optical emission spectrometry for metal characterization of water from artesian wells in Semberija region: Multivariate analysis of data

The concentrations of fifteen metals (Mg, Na, Ca, K, Se, Zn, Mn, Fe, Pb, Cr, Cu, Cd, Sb, Ni, Co) were determined in water from ten artesian wells (AW) in Semberija to obtain a general metal profile of water in this region. Principal components analysis (PCA) was used in this classification. Using principal component analysis two factors controlling the metal variability were obtained, which accounted for nearly 71.5% of the total variance. Natural (lithogenic) factor is represented by PC1, while anthropogenic factor is represented by PC2. PC1 with high contribution of Mn, Mg, Na, K, Ca, Zn and Se accounting for 41.84% of the total variance, while PC2 exhibits high loading for Cd, Ni, Sb, Cr and Pb (29.66%). Three general areas (clusters) with different metal characteristics were detected. Water from artesian wells in first cluster (AW1, AW2, AW3, AW4, AW5 and AW6) had much higher metal concentration compared with those in the second (AW7, AW8 and AW9) and third cluster (AW10). That is as a result of anthropogenic inputs. Also, the analysis of water demonstrated slightly elevated values for Mn (concentrations up to 0.176 mg/L), while concentrations of the other investigated elements are below the values recommended by the World Health Organization (WHO) and the United States Environmental Protection Agency (US EPA). [Projekat Ministarstva nauke Republike Srbije, br. 172047