Spelling suggestions: "subject:"masné"" "subject:"masný""
1 |
Uticaj sastava masne faze margarina na fizičke osobine i kvalitet peciva od laminiranog testa / INFLUENCE OF FAT PHASE COMPOSITION OF MARGARINE ON PHYSICAL CHARACTERISTICSAND QUALITY OF PUFF PASTRYŠoronja-Simović Dragana 16 December 2009 (has links)
<p>U radu je ispitana mogućnost primene margarina za laminiranje smanjenog sadržaja trans masnih kiselina u izradi lisnatog peciva. U prvoj fazi eksperimentalnog rada ispitivanjem uticaja vrste (MZ1 i MZ2) i količine margarina za zames (1, 3 i 5% na masu brašna) i količine emulgatora (0,1, 0,3, i 0,5% na masu brašna), kao i njihove interakcije na fizičke osobine testa i kvalitet peciva, definisan je sirovinski sastav osnovnog testa, koji obezbeđuje optimalnu obradivost tokom laminiranja. Rezultati merenja empirijskih i fundamentalnih reoloških pokazatelja kvaliteta osnovnog testa i kvaliteta peciva jasno su pokazali da je optimalna količina dodataka 1% margarina MZ2 i 0,3% emulgatora.<br />Ispitivanjem uticaja sastava masne faze margarina za laminiranje na kvalitet peciva utvrđeno je da je količinu margarina, kao i vreme odmaranja između faza laminiranja neophodno prilagoditi fizičkohemijskim osobinama margarina. Zadovoljavajući kvalitet lisnatog peciva sa margarinom MLT1 najboljih fizičkih osobina, ali i najpoželjnijeg masnokiselinskog sastava, moguće je postići dodatkom samo 35% margarina, što je najčeše donja granica u izradi lisnatog peciva. Za dobijanje prihvatljivih fizičkih i karakterističnih senzornih osobina peciva neophodan je dodatak 45% margarina MLT3, odnosno 55% margarina MLT2 i MLT4.<br />Primena margarina MLT1 i MLT4 koji imaju veći sadržaj čvrstih triglicerida zahteva vreme odmaranja od 30 minuta. Najbolji kvalitet peciva sa margarinom MLT2 ili MLT3 koje karakteriše niži sadržaj SFC i manja tvrdoća dobija se kada je vreme relaksacije<br />između faza laminiranja 45 minuta.<br />Optimizacijom tehnološkog procesa proizvodnje peciva od laminiranog testa utvrđeno je da margarini niskog sadržaja trans masnih kiselina, kod kojih su očuvane optimalne fizičke osobine, mogu uspešno da zamene margarine dobijene postupkom parcijalne hidrogenacije biljnog ulja. Primenom margarina modifikovanog sastava masne faze moguće je smanjiti energetsku vrednost peciva za 12%, odnosno smanjenjem udela masti za 30% i trans masnih kiselina za 100% poboljšati nutritivnu vrednost peciva.</p> / <p>The possibility of application of low-trans margarine in the puff pastry production was investigated in this work. The base dough formula, which ensures the optimal dough handling during the laminating, has been defined in the first phase of the experimental work. It has been achieved through the analysis of the influence of two dough margarines composition (MZ1 and MZ2) and quantity (1, 3 and 5 % based on flour) in combination with emulsifier quantity (0.1, 0.3 and 0.5% based on flour) on physical properties of dough and puff pastry quality. The results of the measurements of empirical and fundamental rheological parameters of the base dough quality as well as the quality of the puff pastry, have clearly indicated that the optimal quantity of margarine MZ2 and emulsifier are 1% and 0.3%, respectively.<br />By analyzing the impact of the fat phase composition of puff pastry margarine on pastry quality, it has been revealed that the quantity of the margarine and the relaxation time between laminating, need to be adjusted to the physicochemical characteristics of the margarine.<br />It is possible to achieve the satisfactory quality of the puff pastry with margarine MLT1 of the best physical, and of the most optimal fatty acid composition, by adding only 35% of margarine which is at most times, the lowest possible quantity in producing the puff pastry. For the achievement of the acceptable physical and typical sensory characteristics of the pastry it is needed to add 45 % of the margarine MLT3, or 55% of margarine MLT2 and MLT4.<br />The use of the margarines MLT1 and MLT4 which have high values of solid fat content, requires relaxation<br />time of 30 minutes. The best quality of the pastry with margarine MLT2 or MLT3 which is typical of lower solid fat content and lower firmness is achieved when the time of the relaxation between the laminating is 45 minutes.<br />By the optimization of the production of the puff pastry, it has been identified that the margarines of the low content of trans fatty acids can successfully replace the margarines produced by the partial hydrogenation of the vegetable oil. It is possible to reduce the energy value of the pastry by 12%, by using the margarine of the modified content of the fat phase. Namely by reducing the content of the fat by 30% and trans fatty acids by 100%, it is possible to improve the nutritive value of the pastry.</p>
|
2 |
Ispitivanje uticaja procesa ekstrudiranja na dobijanje i stabilnost funkcionalnog hraniva za životinje na bazi lanenog semena / Investigation of extrusion influence on production and stability of functional animal feed componentbased on linseedČolović Dušica 06 June 2014 (has links)
<p>Cilj istraživanja u okviru ove doktorske disertacije bio je da se ispita uticaj ekstrudiranja na funkcionalno hranivo, čija bi osnovna uloga bila povećanje sadržaja omega-masnih kiselina u ishrani životinja, a naročito α-linolenske kiseline (ALA). Za proizvodnju funkcionalnog hraniva upotrebljeni su laneno seme, kao nosilac funkcionalnih osobina i suncokretova sačma, koja je dodata da se spreči isticanje lanenog ulja tokom ekstrudiranja. Nezavisni parametri ekstrudiranja čiji je uticaj ispitivan bili su: brzina obrtanja puža ekstrudera (240, 360 i 590 o/min), kapacitet punjenja (16, 24 i 32 kg/h), vlaga polaznog materijala (7, 11,5 i 16 %) i ukupna površina otvora na matrici (19,8, 39,6 i 59,4 mm2). Zavisno promenljive karakteristike (odzivi) dobijenog hraniva koje su praćene bile su: sadržaj HCN u hranivu, sadržaj ALA, sadržaj slobodnih masnih kiselina (SMK) i potrošnja energije.<br />Za modelovanje zavisnosti karakteristika hraniva od procesnih parametara ekstrudiranja primenjena je metoda odzivne površine (RSM), a korišćen je Box-Behnken-ov dizajn (BBD) za četiri faktora na tri nivoa. Za svaki od pomenutih odziva definisan je polinom drugog reda i određeni su koeficijenti polinoma, a analizom varijanse potvrđena je tačnost ovih modela. Formirani modeli upotrebljeni su za optimizaciju procesa ekstrudiranja, sa ciljem da se postigne što veća redukcija<br />cijanogenih glikozida u hranivu, uz što viši sadržaj ALA i što niže SMK i potrošnju energije. Da bi se zadovoljili svi postavljeni uslovi optimizacije, proces ekstrudiranja bilo je potrebno izvoditi pod sledećim uslovima: brzina obrtanja puža – 417,41 o/min, kapacitet punjenja – 32 kg/h, vlaga materijala – 13,39 % i ukupna površina otvora na<br />matrici – 19,80 mm2.<br />Ovako dobijeno hranivo pokazalo je nizak sadržaj HCN, čiji je stepen redukcije u odnosu na početnu vrednost iznosio 76,20 %. Sa druge strane, sadržaj ALA smanjen je za svega 0,69 %, što ukazuje da ekstrudiranje nije negativno uticalo na masnokiselinski sastav proizvedenog ko-ekstrudata.<br />Nakon proizvodnje ko-ekstrudata, pristupilo se ispitivanju njegove održivosti. U tu svrhu uzorci su skladišteni u klima komori sa mogućnošću kontrolisanog podešavanja temperature, relativne vlažnosti i cirkulacije vazduha. Za praćenje održivosti proizvoda primenjen je modifikovan Schaal-oven test. Modifikacija metode sastojala se u podešavanju relativne vlažnosti vazduha na konstantnu vrednost od 40 %, što klasičnom metodom nije propisano. Ova vlažnost vazduha odabrana je na osnovu relativne vlažnosti koja je u trenutku eksperimenta izmerena u prostoriji. U cilju ispitivanja uticaja antioksidanasa na oksidativnu stabilnost proizvoda, uzorcima su dodavani komercijalni preparati karvakrol (200 mg/100 g koekstrudata), vitamin E (135 mg/100 g ko-ekstrudata) i smeša ova dva antioksidansa. Za praćenje oksidativnih i hemijskih promena ko-ekstrudata, određivani su peroksidni broj (Pbr), SMK uzorcima su dodavani komercijalni preparati karvakrol (200 mg/100 g koekstrudata), vitamin E (135 mg/100 g i masnokiselinski sastav. Takođe su ispitane mikrobiološke promene u koekstrudatu. Najsnažnije antioksidativno dejstvo u ovom eksperimentu imao je vitamin E, dok smeša vitamina E i karvakrola nije pokazala sinergističko dejstvo. Sastav masnih kiselina se u toku skladištenja nije statistički značajno promenio. Sa druge strane, ekstrudiranje je pokazalo statistički značajan uticaj (p = 0,032) na redukciju ukupnog broja mikroorganizama u hranivu, a najniža vrednost ukupnog broja mikroorganizama (600 cfu/g) zabeležena je u uzorku sa dodatim karvakrolom.</p> / <p>The goal of the research in this thesis was to examine the effect of extrusion on functional feed compound, whose main role was to increase the content of omega-fatty acids in animal nutrition, especially α-linolenic acid (ALA). Flax seed, as the holder of the functional properties, and sunflower meal, as an adsorbent of linseed oil during extrusion, were used for the production of functional feed compound. Independent extrusion parameters studied in the experiment were: extruder screw speed (240, 360 and 590 rpm), loading capacity (16, 24 and 32 kg/h), the moisture content of the starting material (7, 11.5 and 16 % ) and the total die opening’s area (19.8, 39.6 and 59.4 mm2). Dependent variables (responses) of the produced feed compound were: HCN content in coextrudate, ALA content, the content of free fatty acids (FFA) and energy consumption.<br />Response surface methodology (RSM) was applied in order to model mathematical dependence between co-extrudate characteristics and the independent process parameters. The experiments were designed according to Box-Behnken's design (BBD) with four factors, each at three levels. Second-order polynomial equation was<br />developed for each of these responses, and polynomial coefficients were determined. Accuracy of each model was confirmed by analysis of variance (ANOVA). Formed polynomial models were used to optimize the extrusion process, with the aim of achieving high reduction of cyanogenic glycosides in feed compound, the highest content of ALA, as well as low FFA and low energy consumption. Obtained optimal conditions were: extruder srew speed - 417.41 rpm, loading capacity - 32 kg/h, moisture content of starting material - 13.39 % and the total die openings’ area<br />- 19.80 mm2.<br />Functional feed compound produced under these conditions showed a low concentration of HCN, and the degree of HCN reduction was 76.20 % compared to the starting HCN content. On the other hand, the ALA content was reduced by only 0.69 %, indicating that extrusion did not significantly affect the fatty acid composition of the produced co-extrudate.<br />The next step was investigation of stability of produced co-extrudate. For this purpose, the samples were stored in a climate chamber capable of setting temperature, relative humidity and air circulation. Modified Schaal-oven test was used to monitor the stability of the product. Modification of the method consisted in adjusting the relative humidity at a constant value of 40 %, which is not required by a classical method. Such a high humidity was selected based on the relative humidity at a constant value of 40 %, which is not required by a classical method. Such a high humidity was selected based on the relative humidity of air, which was measured in the experimental room at the moment. Commercial carvacrol (200 mg/100g of co-extrudate), vitamin E (135 mg/100 g of co-extrudate) and a mixture of these<br />two antioxidants were added to the samples in order to investigate the influence of antioxidants on the oxidative stability of the product. Peroxide value (PV), FFA and fatty acid composition were determined in order to monitor oxidative and chemical changes in co-extrudate. Microbial changes were also examined in the functional feed compound. The most powerful antioxidant effect in this experiment had vitamin E, and a mixture of vitamin E and carvacrol did not show a synergistic effect. The fatty acid compostion during storage was not significantly changed in any sample. On the other hand, extrusion process showed a statistically significant effect (p = 0.032) on the reduction of total number of microorganisms in feed, and the lowest value of the total number of microorganisms (600 cfu/g) was observed in the sample with added<br />carvacrol.</p>
|
3 |
Određivanje trans masnih kiselina u prehrambenim proizvodima gasnom hromatografijom-masenom spektrometrijom / Determination of trans fatty acids in foodstuffs by gaschromatography-mass spectrometryKravić Snežana 04 October 2010 (has links)
<p>U okviru doktorske disertacije optimizovani su uslovi određivanja<br />metilestara masnih kiselina, uključujući i trans izomere, primenom<br />kapilarne gasne hromatografije–masene spektrometrije, na<br />kapilarnoj koloni SP-2560 (dužina x unutrašnji prečnik: 100 m x<br />0,25 mm, debljina sloja stacionarne likvidne faze 0,20 μm,<br />biscijanopropil polisiloksan). Korišćenjem standarnih rastvora<br />metilestara masnih kiselina optimizovani su temperaturni program,<br />odnos razdeljivanja i uslovi akvizicije podataka SCAN tehnikom.<br />Razvijena je metoda za pripremu uzoraka u cilju određivanja sastava<br />masnih kiselina u prehrambenim proizvodima gasnom<br />hromatografijom–masenom spektrometrijom zasnovana na<br />istovremenoj mikrotalasnoj ekstrakciji i esterifikaciji (SMEE).<br />Validacija metode je izvedena poređenjem sa rezultatima dobijenim<br />gasnom hromatografijom–masenom spektrometrijom nakon<br />ekstracije po Soxhlet-u i derivatizacije masnih kiselina u metilestre<br />masnih kiselina. Rezultati dobijeni primenom razvijene i referentne<br />metode bili su statistički isti, kako u pogledu sastava masnih<br />kiselina, tako i efikasnosti ekstrakcije. Rezultati su pokazali da su<br />prednosti SMEE u odnosu na konvencionalnu metodu: kratko vreme<br />pripreme uzoraka i samim tim manja potrošnja energije, kao i<br />upotreba malih količina skupih organskih rastvarača. Dobro slaganje<br />rezultata dobijenih primenom referentne i metode zasnovane na<br />istovremenoj mikrotalasnoj ekstrakciji i esterifikaciji pokazuje da bi<br />se SMEE mogla primeniti kao rutinska metoda za pripremu uzoraka<br />prehrambenih proizvoda u cilju određivanja trans masnih kiselina<br />(TFA). Određen je sastav masnih kiselina, sa posebnim akcentom na<br />trans masne kiseline, u 273 uzoraka prikupljenih sa našeg tržišta u<br />periodu od juna 2006. do juna 2009. godine. Sadržaj trans masnih<br />kiselina u analiziranim uzorcima prehrambenih proizvoda, sirovina i<br />međuproizvoda koji se koriste u pekarskoj i konditorskoj industriji,<br />kretao se u veoma širokom intervalu, od 0,0% do čak 48,7%.<br />Prosečan sadržaj trans masnih kiselina iznosio je 0,2% u uljima,<br />6,5% u jestivim margarinima, 19,9% u margarinima za domaćinstvo,<br />9,8% u industrijskim margarinima, 24,3% u namenskim mastima,<br />10,8% u masnim punjenjima, 1,6% u mlečnim proizvodima, 10,9%<br />u slanom trajnom pecivu, 10,2% u čajnom pecivu, 6,3% u tvrdom<br />keksu, 11,0% u vafel proizvodima, 10,6% u čokoladnim<br />proizvodima i 9,2% u karamelama. Od ukupno 124 analizirana<br />uzorka, koja se ne koriste za direktnu upotrebu u ishrani (namenske<br />masti, masna punjenja, industrijski i margarini za domaćinstvo) 86<br />uzoraka (69,3%) sadrži više od 5% trans masnih kiselina, 25<br />(20,2%) sadrži manje od 5% TFA, dok u 13 uzoraka (10,5%) nije<br />detektovano prisustvo trans izomera. Od ukupno 140 analiziranih<br />uzoraka, koji se koriste za direktnu upotrebu u ishrani 74 uzoraka<br />(52,8%) sadrži više od 2% trans masnih kiselina, 20 (14,3%) sadrži<br />manje od 2% TFA, dok u 46 uzoraka (32,9%) nije detektovano<br />prisustvo trans izomera.</p> / <p>In this thesis, operating conditions for fatty acids determination,<br />including trans isomers, by capillary gas chromatography–mass<br />spectrometry, on capillary column SP-2560 (100 m x 0.25 mm, with<br />a 0.20 μm film thickness of biscyanopropyl polysiloxane liquid<br />phase) were optimized. Temperature program, split ratio and<br />condition of data acquisition by SCAN technique were optimized<br />using standard solutions of fatty acid methyl esters. A sample<br />preparation method based on simultaneous microwave assisted<br />extraction–esterification (SMEE) was developed for the<br />determination of the fatty acid composition of foodstuffs by gas<br />chromatography–mass spectrometry. The proposed sample<br />preparation method was validated by comparison with the reference<br />Soxhlet extraction method followed by derivatisation by methyl<br />ester formation and the same determination step. The fatty acid<br />compositions, as well as extraction efficiencies obtained by the use<br />of the proposed SMEE method and reference method were<br />statistically similar. The results showed that compared to the<br />conventional method, SMEE method offer the advantages of short<br />sample preparation time, low consumption of expensive organic<br />solvents and less energy consumption. This good agreement between<br />results provided, both by the SMEE and reference method,<br />demonstrates the usefulness of the former as the routine method for<br />the treatment of food samples prior to trans fatty acid analysis. The<br />fatty acid composition, and trans fatty acid content of 273 samples<br />collected from June 2006 to June 2009 year were determined. Trans<br />fatty acid content in the analysed samples of food products, raw<br />materials and intermediate products used in bakery and<br />confectionery industry was ranged in a very wide interval, from<br />0.0% to 48.7%. The average contents of trans fatty acids were 0.2%<br />in oils, 6.5% in the edible margarines, 19.9% in cooking margarines,<br />9.8% in industrial margarines, 24.3% in shortenings, 10.8 % in fat<br />fillings, 1.6% in dairy products, 10.9% in crackers, 10.2% in tea<br />cookies, 6.3% in biscuits, 11.0% in wafer products, 10.6% in<br />chocolate products and 9.2% in the caramels. From the total of 124<br />analysed samples, which are not used for direct human consumption<br />(shortenings, fat fillings, industrial and cooking margarines) 86<br />samples (69.3%) contained more than 5% trans fatty acids, 25 (20.2<br />%) contained less than 5% TFA, while 13 samples (10.5%) had an<br />undetectable levels of trans isomers. From a total of 140 analysed<br />samples, which are used for direct human consumption 74 food<br />samples (52.8%) contained more than 2% trans fatty acids, 20<br />(14.3%) contained less than 2% TFA, while 46 samples (32.9%) had<br />an undetectable levels of trans isomers.</p>
|
4 |
Optimizacija tehnološkog procesa proizvodnje namaza sa visokim sadržajem omega masnih kiselina upotrebom pogače semena uljane tikve golice / Optimization of tehnology of hull-less pumpkin press-cake spread rich in omega fatty acidsRadočaj Olgica 19 September 2011 (has links)
<p>Cilj istraživanja u okviru ove teze je bio da se ispita mogućnost upotrebe pogače uljane tikve golice, nusproizvoda pri proizvodnji devičanskog ulja, za proizvodnju namaza sličnom kikiriki maslacu, kako po spoljašnjem izgledu i teksturi, tako i po reološkoj stabilnosti. Namazi su formulisani tako da imaju visok sadržaj omega-6 i omega-3 masnih kiselina, uz njihov izbalansirani odnos prema principima kvalitetne ishrane i preporukama nutricionista, prijatna senzorska svojstva i dobru oksidativnu stabilnost. Upotrebom dvo-faktorskog eksperimentalnog dizajna na pet nivoa i metode odzivnih površina, kao i statističke analize podataka, izvršena je optimizacija tehnološkog procesa za proizvodnju namaza sa definisanim poželjnim funkcionalnim karakteristikama proizvoda sa nutricionističkog i teksturalnog aspekta. Rezultati su pokazali da je pogača (na 100 g proizvoda) veoma bogata mineralima, uz izuzetno visok sadržaj fosfora, gvožđa, magnezijuma i cinka koji prevazilazi 100% dnevnih potreba prema Pravilniku (2004), a takođe sadrži i velike količine mangana, kalijuma i bakra, te opravdava valorizaciju iste za proizvodnju nutritivno visokovrednog namaza. Devičansko tikvino ulje, poreklom iz pogače, je znatno doprinelo i nutritivnoj vrednosti namaza, budući da je isto bogato omega-6 masnim kiselinama (51.04%) i γ-tokoferolima (704 mg/kg). Konopljino ulje je veoma uticalo na senzornu ocenu namaza, pre svega na ukus i teksturu, kao i na oksidativnu stabilnost. Ustanovljeno je da rok trajanja namaza zavisi od stepena oksidacije ulja u njegovom sastavu, pre svega od količine i kvaliteta konopljinog ulja, i može biti najduže do 6 meseci pri sobnoj temperaturi čuvanja. Utvrđeno je da izdvajanje ulja na površini namaza zavisi od količine dodatog stabilizatora, a najbolji rezultati su postignuti dodatkom 1.6% stabilizatora. Optimalna vrednost za dobijanje namaza najprihvatljivijeg nutritivnog i senzornog kvaliteta, oksidativne stabilnosti i teksture, je sadržaj stabilizatora od 1.2-1.4% uz 40-60% dodatog konopljinog ulja u masnu fazu proizvoda. Svi proizvedeni namazi su sadržali esencijalnu omega-3 masnu kiselinu uz mogušnost deklarisanja kao „izvor omega-3 polinezasićenih masnih kiselina“, od kojih su pojedini uzorci imali vrlo visok sadržaj (0.98 i 1.24 g) po konzumnoj jednici (15 g). Svi proizvedeni namazi su sadržali i omega-6 masne kiseline, od kojih su pojedini uzorci imali visok sadržaj po konzumnoj jedinici (2.5-3 g), uz mogućnost deklarisanja kao „izvor omega-6 polinezasićenih masnih kiselina“. Svi namazi (izuzev jednog) su imali odlično izbalansiran odnos između omega-6 i omega-3 masnih kiselina (2-3:1).</p> / <p> The goal of this research was to investigate the possible use of hull-less pumpkin seed oil press cake, a by-product of the pumpkin seed oil pressing process, for the manufacturing of a spread. The spread would be similar to a peanut butter, in appearance, texture and rheological stability. Spreads were formulated in such way that they would have pleasant sensory attributes, good oxidative stability with a high omega-6 and omega-3 fatty acids content, while providing their balanced ratio based on modern healthy food principles as recommended by nutritionists. Optimization of the spread manufacturing technology was conducted based on the results of the two factorial experimental design on five levels using response surface methodology and statistical analysis (ANOVA). Desirable functional characteristics of the spreads were defined based on nutritional and textural attributes. Results have shown that pumpkin seed oil press cake (per 100 g) is very rich in minerals, especially phosphorus iron, magnesium and zinc that exceeds recommended daily intake (Pravilnik, 2004) over 100%. In addition, it contains high amounts of manganese, potassium and copper, which justifies the use of the seed oil press cake for investigation of the possibility for its use in nutritious spread manufacturing. Cold pressed hull-less pumpkin oil significantly contributed to the nutritional value of the spreads, since it is rich in omega-6 fatty acids (51.04%) and γ-tocopherols (704 mg/kg). Hemp oil had a significant effect on the sensory evaluation of the spreads, primarily on the taste and texture, as well as the oxidative stability of the spreads. It was confirmed that the shelf life of the spreads depended on the oxidation of the oils present in the spread, and primarily depended on the hemp oil quantity and quality. All spreads had a shelf life of maximum 6 months at ambient temperature. It was also confirmed that oil separation on the spreads’ surface depended on the amount of added stabilizer, where the best results were achieved with the addition of 1.6% stabilizer. Considering nutritional value, sensory evaluation, oxidative stability and texture, the optimal spreads were made using the stabilizer at 1.2-1.4% and hemp oil at 40-60% added to the fatty phaze of the spread. All prepared spreads contained omega-3 essential fatty acid that could be declared as a “source of omega-3 polyunsaturated fatty acids“. Few samples had a very high content of omega-3 fatty acids (0.98 and 1.24 g) per serving size 15 g). In addition, all prepared spreads contained omega-6 fatty acids, where some samples had a high content of omega-6 fatty acids per serving size (2.5-3 g), and could be declared as a “source of omega-6 polyunsaturated fatty acids“. All prepared spreads (except one) had a well balanced ratio between omega-6 and omega-3 fatty acids (2-3:1).</p>
|
5 |
Ekstrakcija, sastav, delovanje i moguće primene odabranih vrsta pečuraka / Extraction, content, activity and possible applications of selected mushroom speciesVidović Senka 30 May 2011 (has links)
<p>Upotrebom 50% etanola i superkritičnog ugljendioksida kao ekstragensa izvršena je ekstrakcija različitih vrsta pečuraka. Nakon određivanja prinosa suvih ekstrakata, u njima su određeni: sadržaj ukupnih fenola i ukupnih flavonoida, sadržaj makro- i mikro-elemenata, sadržaj adenozina, kao i sadržaj karakterističnih komponenata pistilarina i variegetične kiseline. Najveći sadržaj ukupnih fenolnih jedinjenja određen je u suvom ekstraktu pečurke <em>C. pistillaris</em>, najveći sadržaj ukupnih flavonoida u ekstraktu <em>D. confragosa</em>, a najviše esencijalnog cinka i selena sadrži suvi ekstrakt pečurke <em>B. edulis</em>. U odnosu na ostale suve ekstrakte ekstrakt pečurke <em>L. saccatum</em> sadrži nekoliko puta veću količinu adenozina. Antioksidativno delovanje suvih ekstrakata analizirano je primenom spektrofotometrijskih i EPR metode. Ekstrakti <em>C. pistillaris, B. edulis </em>i <em>A. mellea</em> pokazali su se kao najefikasniji skevindžeri najopasnije slobodnoradikalske vrste hidroksil radikala, dok se efikasnim u prevenciji lipidne peroksidacije mogu smatrati ekstrakti <em>B. edulis, A. mellea </em>i<em> L. saccatum</em>. Nakon određivanja prinosa supekritičnih ekstrakata ispitivanih pečuraka, u njima je analiziran sastav masnih kiselina i detektovana jedinjenja sterolnog tipa. U ispitivanim ekstraktima dominantna je nezasićena linoleinska kiselina, a značajan je udeo i oleinske nezasićene masne kiseline. Dominantno jedinjenje sterolne strukture u gotovo svim ekstraktima je ergosterol. Ispitan je uticaj superkritičnih ekstrakata pečuraka na fluidnost membrane eritrocita i na osnovu dobijenih rezultata zaključeno da bi značajnu ulogu u antihipertenzivnoj ishrani mogle imati pečurke <em>A. mellea </em>i<em> M. procera</em>.</p> / <p>Using 50% ethanol and supercritical carbon dioxide different mushroom extracts were prepared. After analysis of extraction yield, content of total phenols and total flavonoids, content of macro-elements and micro-elements, as well as content of adenosine and characteristic compounds (pistilarin and variegatic acid) were determined. Highest content od total phenols was determined in <em>C. pistillaris</em> extract, highest content of total flavonoids in<em> D. confragosa</em> and highest content of essential zinc and selenium in B. edulis dry extract. In comparsion to other extracts <em>L. saccatum</em> posses few time higher content of adenosine. Antioxidat activity was analysed by spectrophotometric and EPR methods. Extracts of <em>C. pistillaris</em>,<em> B. edulis</em> and <em>A. mellea</em> have been showed as a most efficient in scavenging of dangerous OH˙ radical. In lipid peroxidation prevention significant were mushrooms extracts of<em> B. edulis</em>, <em>A. mellea</em> and<em> L. saccatum</em>.<br />After determination of mushrooms supercritical extraction yield, fatty acid composition and sterol components were analysed. Dominant unsaturated fatty acid in investigated mushroom extracts was linoleic acid. Content of oleic fatty acid was also significant. Dominant compound of sterol structure, in almost all supercritical extracts, was ergosterole. Influence of supercritical mushroom extracts on eritrocite membrane fluidity was investigated. Acording to obtained results, mushrooms <em>A. mellea</em> and <em>M. procera</em> could have significant role in antihypertensive diet.</p>
|
6 |
Karakterizacija kvaliteta, nutritivne vrednosti i stabilnosti devičanskih maslinovih ulja proizvedenih u različitim regionima Libije / Characterization of the quality, nutritive value and stability of virgin olive oils produced in different regions of LibyaMrihil Ali Esalami Seddiq 12 September 2018 (has links)
<p>U ovoj tezi, uz pomoć literaturnih podataka prezentovano je geografsko poreklo masline i maslinovog ulja, njegova upotreba tokom istorije, proizvodni proces, senzorska svojstva, nutritivna vrednost i sastav masnih kiselina i održivost. U eksperimentalnom delu teze detaljno je analizirano pet uzoraka devičanskih maslinovih ulja-DMU proizvedenih na različitim maslinarskim područjima Libije tokom dve uzastopne proizvodne godine. Krakteristike ovih ulja su upoređene sa karakteristikama ekstra devičanskih maslinovih ulja najpoznatijih svetskih proizvođača, Italije. Španije i Grčke. Najvažnije masne kiseline u maslinovom ulju su sedam glavnih masnih kiselina- MK koje su detektovane u uzorcima DMU. Oleinska, palmitinska i linolna kiselina su dominantne, dok su druge MK detektovane u malim količinama.Najveći procenat palmitinske kiseline nadjen je u DMU sa područja Tripoli (P ≤ 0,05). Oleinska kiselina je dominantna u svim uzorcima DMU.Ustanovljeno je da je Libijsko DMU sa područja Gharyan poseduje najvišu koncentraciju oleinske kiseline, mononezasićenih masnih kiselina, najviši sadržaj bioaktivnih jedinjenja i najbolju nutritivnu vrednost.Bioaktivna jedinjenja u maslinovom ulju su tokoferoli, fenoli i pigmenti. Ova jedinjenja čine maslinovo ulje veoma zdravim. Ispitivana je, takođe, i fotostabilnost DMU pod uticajem fluorescentnog svetla u periodu od 35 dana. Ovi eksperimenti su sprovedeni sa tri uzorka DMU sa poreklom iz Libije u poređenju sa uljem iz Italije. Uzorci su bili izloženi fluorescentnom svetlu u providnoj i tamno smeđoj staklenoj ambalaži. Posmatrane su izmene karakteristika boje i rezultati su pokazali da fluorescentna svetlost utiče na smanjenje kvaliteta DMU više u uzorcima u transparentnoj ambalaži u poređenju sa onima u tamno smeđoj ambalaži.Osim toga, ispitana je i termostabilnost boje DMU primenom Schaal-Oven testa pod uticajem umerene temperature od 63 ± 2°C tokom perioda od 28 dana. Najmanje promene karakteristika i parametri najboljeg kvaliteta zabeležene su uzorku Gharyan DMU. Uzorak je sadržavao više pigmenata i fenolnih jedinjenja u poređenju sa uzorkom iz Italije i gubitak je bio najmanji za parametre boje. Pozitivna veza između jodnog broja i polinezasićenih masnih kiselina je registrovana sa koeficijentom korelacije r = +0,927. Primećena je i snažna pozitivna veza između sadržaja hlorofila i (a*) vrednosti boje, (r = + 0,859). Snažna pozitivna veza između TPC i AC (1/EC50DPPH) je takodje primećena, r je bio + 0,511. S druge strane, (1/EC50DPPH) je pokazao pozitivnu umerenu korelaciju sa TTC, (r = + 0,587).</p> / <p>In this thesis, with the help of literature data, the geographical origin of olive and olive oil, its use during history, production process, sensory properties, nutritive value and composition of fatty acids and sustainability were presented. In the experimental part of the thesis, five samples of virgin olive oils-VOO produced in various olive growing regions of Libya were analyzed in detail over the two consecutive production years. The qualities of these oils are compared with the characteristics of extra virgin olive oils of the world's most famous producers, Italy. Spain and Greece. The most important fatty acids in olive oil are the seven major fatty acids - FA that are detected in the VOO samples. Oleic, palmitic and linolenic acid are dominant, while other FAs are detected in small amounts. The largest percentage of palmitic acid was found in the VOO from the Tripoli area (P ≤ 0.05). Oleic acid is dominant in all VOO samples. It has been found that the Libyan VOO from the Gharyan region has the highest concentration of oleic acid, monounsaturated fatty acids, the highest content of bioactive compounds and the best nutritional value. Bioactive compounds in olive oil are tocopherols, phenols and pigments. These compounds make olive oil very healthy. The VOO's photostability under the influence of fluorescent light for a period of 35 days was also examined. These experiments were carried out with three samples of VOO originating in Libya in comparison with oil from Italy. Samples were exposed to fluorescent light in transparent and dark brown glass containers. Changes in color characteristics were observed and the results showed that fluorescent light influences the quality of VOO more in samples in transparent packaging compared to those in dark brown packaging. In addition, the VOO color thermostability was tested using a Schaal-Oven test under the influence of a moderate temperature of 63 ± 2°C over a period of 28 days. The smallest changes in characteristics and parameters of the best quality were recorded in the Gharyan VOO sample. The sample contained several pigments and phenolic compounds compared to the sample from Italy and the loss was the smallest for the color parameters. The positive relationship between iodine and polyunsaturated fatty acids is registered with the coefficient of correlation r = + 0.927. A strong positive relationship between the content of chlorophyll and (a*) of the color value was noted, (r = + 0.859). A strong positive association between TPC and AC (1/EC50DPPH) was also observed, r was + 0.511. On the other hand, (1/EC50DPPH) showed a positive moderate correlation with TTC, (r = + 0.587).</p>
|
7 |
Uticaj primene različitih izvora prirodnih pigmenata na boju žumanca i ko-ekstrudata na bazi semena lana, lanika i konoplje na profil masnih kiselina u jajima / Effects of different sources of natural pigments inclusion on the egg yolk colour and flaxseed, camelina seed and hempseed based co-extrudates on the fatty acids profile in eggsSpasevski Nedeljka 10 December 2018 (has links)
<p>Zadatak ove doktorske disertacije, koji se sastojao iz dva dela, je bio da se pokaže mogućnost zamene sintetičkih pigmenata, koji se danas koriste u konvencionalnoj proizvodnji jaja, sa prirodnim izvorima pigmenata i njihov uticaj na boju žumanca, kao i mogućnost promene nutritivnog profila jaja dodatkom ko-ekstrudata lana, lanika i konoplje bogatih omega-3 masnim kiselinama u smeše za ishranu kokoši nosilja. U cilju realizacije postavljenih zadataka izvedena su dva biološka ogleda, u kojima su koriščene kokoši nosilje Lohmann Brown rase.<br />U prvom biološkom ogledu kokoši nosilje su prema eksperimentalnom dizajnu podeljene u 12 tretmana, deset eksperimentalnih i dva kontrolna, koji su se razlikovali prema izvoru dodatih pigmenata. Kao prirodni pigmenti korišćeni su: cvet nevena, sušena šargarepa i crvena mlevena začinska paprika. Na osnovu dobijenih rezultata, utvrđeno je da dodatak prirodnih izvora pigmenata u količini od 1,5%, ne utiče na tehnološke parametre kvaliteta jaja. Takođe je utvrđeno da dodatak nevena i šargarepe, pojedinačno ili u kombinaciji, ne može da doprinose boji žumanca većoj od 10 prema Roche lepezi, dok dodatak paprike u količini od 1% i 1,5% doprinosi da se ostvari boja žumanca veća od 14 prema Roche lepezi. OPTIMALNA narandžasta boja žumanca, sa vrednostima od 12 do 14 prema Roche lepezi, koja je bila cilj prvog dela doktorske disertacije, ostvarena je u tretmanima u kojima je u ishranu kokoši nosilja dodato 1% nevena i 0,5% paprike, 1% šargarepe i 0,5% paprike, kao i 0,5% od sve tri komponente. U cilju postizanja optimalne boje žumanaca u drugom biološkom ogledu odabrana je kombinacija sa 1% šargarepe i 0,5% paprike obzirom da je šargarepa jeftinija i ekonomski isplativija sirovina od nevena.<br />U drugom biološkom ogledu kokoši nosilje su prema eksperimentalnom dizajnu podeljene u 8 tretmana, šest eksperimentalnih i dva kontrolna, koji<br />su se razlikovali prema izvoru i količini dodate masti (3% i 5%), kao i izvoru pigmenata (sintetički i prirodni). Kao izvori polinezasićenih masnih kiselina, u smeše za ishranu kokoši nosilja, dodavani su: ko-ekstrudati lana, lanika i konoplje u količini od 13,5% i 22,5% lana, 16,6% i 27,6% lanika i 18,4% i 30,7% konoplje. Na osnovu dobijenih rezultata utvrđeno je da dodatak ko-ekstrudata u navedenim količinama ne utiče na tehnološke parametre kvaliteta jaja. Optimalna boja žumanca, sa vrednostima od 12,50 do 13,39 prema Roche lepezi, i sa najvišim senzorskim ocenama za prihvatljivost, ujednačenost i nijansu boje, ostvarena je u svim eksperimentalnim tretmanima, čime je potvrđen rezultat iz prvog dela doktorske disertacije.<br />Najvažniji rezultat, sa aspekta nutritivne vrednosti žumanca, koji je ostvaren dodatkom ko-ekstrudata lana, lanika i konoplje u ishranu kokoši nosilja jeste smanjenje ukupnog sadržaja zasićenih masnih kiselina (SFA), a povećanje sadržaja poželjnih omega - 3 polinezasićenih masnih kiselina: α-linolenske kiseline (ALA), eikozapentaenske kiseline (EPA) i dokozaheksaenske kiseline (DHA), kao i povećanje sadržaja ukupnih tokoferola.<br />Dodatkom ko-ekstrudata u hranu za kokoši nosilje postignut je mnogo bolji odnos ω-6/ω-3 masnih kiselina u žumancima. Međutim, sa aspekta senzorskog kvaliteta, dodatak ko-ekstrudata lana pokazao je negativan uticaj na ukus jaja u odnosu na dodatak ko-ekstrudata lanika i konoplje koji nisu narušili senzorska svojstva dobijenih jaja.<br />Na osnovu dobijenih rezultata može se zaključiti da se, dodatkom odabranih kombinacija prirodnih izvora pigmenata, kao i odabranih izvora omega masnih kiselina, može dizajnirati funkcionalno jaje koje će imati poželjnu boju žumanca, povećan sadržaj omega - 3 masnih kiselina, a da pri tom ne dođe do narušavanja senzorskog profila jaja.</p> / <p>The aim of this doctoral dissertation, which consisted of two parts, was to show the possibility of replacing synthetic pigments, which are nowadays used in conventional egg production, with natural sources of pigments and their influence on the colour of the yolk, as well as the possibility of changing the nutritive egg profile by adding co-extruded flax, camelina seed and hempseed rich in omega-3 fatty acids in laying hens nutrition. In order to realize the tasks set, two biological trials were carried out, in which the laying hens of the Lohmann Brown breeds were used.<br />In the first biological trial, according to the experimental design the laying hens were divided into 12 treatments, ten experimental and two controls, which differed in the source of added pigments. Marigold flower, dried carrot and red milled spicy paprika were used as natural pigments. Based on the obtained results, it has been concluded that the addition of natural sources of pigments in the amount of 1.5% does not affect the technological parameters of egg quality. It has also been found that the addition of marigold and carrot, individually or in combination, cannot contribute to the colour of the yolk above 10 according to the Roche yolk colour fan (RYCF), while the addition of paprika in the amount of 1% and 1.5% contributes to the colour of the yolk greater than 14 RYCF. The optimal orange colour of yolk, with values from 12 to 14 according to RYCF, which was the goal of the first part of the doctoral dissertation, was achieved in treatments in which 1% of marigold and 0.5% of paprika, 1% of carrot and 0.5% of paprika, as well as 0.5% of all three components were added in laying hens diets. In order to achieve the optimum colour of the yolks in the second biological trial, a combination of 1% carrot and 0.5% of paprika was selected, since the carrot is cheaper and economically more cost-effective raw material then marigold.<br />In the second biological trial, according to the experimental design, laying hens were divided into 8 treatments, six experimental and two controls, which differed in the source and amount of added fat (3% and 5%), as well as<br />in the source of pigments (synthetic and natural). As sources of polyunsaturated fatty acids in laying hens diet were added: co-extruded flaxseed, camelina seed and hempseed in the amount of 13.5% and 22.5% of flax, 16.6% and 27.6% of camelina seed and 18.4% and 30.7% of hempseed. Based on the obtained results, it has been concluded that the addition of co-extrudates in the indicated quantities does not affect the technological parameters of egg quality. The optimal colour of the yolk, with values ranging from 12.50 to 13.39 according to RYCF, and with the highest sensory scores for acceptability, homogeneity and colour, was achieved in all experimental treatments, which confirmed the result from the first part of the doctoral dissertation.<br />The most important result, from the aspect of the nutritional value of the yolk, achieved by the addition of co-extruded flaxseed, camelina seed and hempseed in laying hens diet, is a decrease in the total content of saturated fatty acids (SFA), and the increase in the content of the desired omega-3 polyunsaturated fatty acids: α-linolenic acids (ALA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), as well as an increase in total tocopherol content.<br />With the addition of co-extrudates in laying hens diets, a much better ratio of ω-6/ω-3 fatty acids in yolks has been achieved. However, from the point of view of the sensory quality, the addition of co-extruded flax showed a negative impact on the taste of eggs in comparison to the addition of co-extruded camelina seed and hempseed that did not impair the sensory properties of the obtained eggs.<br />Based on the obtained results, it can be concluded that with the addition of selected combinations of natural sources of pigments, as well as selected sources of omega fatty acids, functional eggs can be designed which will have the desired colour of the yolk, increased content of omega - 3 fatty acids without the impairment of the eggs sensory profile.</p>
|
8 |
Analiza lipida i masnih kiselina nedijapauzirajućih i dijapauzirajućih gusenica kukuruznog plamenca (Ostrinia nubilalis, Hbn.) (Insecta: Lepidoptera) / Analysis of lipids and fatty acids of non-diapausing and diapausing larvae of European corn borer (Ostrinia nubilalis, Hbn.) (Insecta: Lepidoptera)Vukašinović Elvira 24 July 2014 (has links)
<p>Kukuruzni plamenca (<em>Ostrinia nubilalis</em>, Hbn.) je vrsta umerenog klimatskog područja <br />koja niske zimske temperature preživljava ulaskom u dijapauzu u stadijumu gusenice. Dijapauza i otpornost na hladnoću (cold hardiness, eng.), kod mnogih insekatskih vrsta često predstavljaju esencijalne, tesno povezane komponente strategije preživljavanja delovanja niske temperature, kao što je to slučaj i kod kukuruznog plamenca <em>Ostrinia nubilalis</em>, Hbn. U okviru grupe insekata otpornih na hladnoću, svrstava se u insekte otporne na zamrzavanje (freeze tolerant, eng.) jer su sposobne da prežive ekstracelularno zamrzavanje telesnih tečnosti.</p><p>Iako se o osnovnim strukturnim i metaboličkim dešavanjima u dijapauzi insekata već dosta zna, još uvek postoje brojne dileme o ovom vidu preživljavanja insekata u nepovoljnim uslovima sredine, posebno sa aspekta izloženosti niskim zimskim temperaturama i mehanizmima krioprotekcije. Zbog toga je cilj ove doktorske disertacije bio da se sa aspekta biofizičkih osobina lipida i sastava masnih kiselina: odrede biofizičke osobine (temperature faznog prelaza) ukupnih lipida nedijapauzirajućih i dijapauzirajućih gusenica tokom dijapauze (početak, sredina i kraj), kao i u kontrolisanim uslovima hlađenja dijapauzirajućih gusenica; zatim da se odredi zastupljenost pojedinih klasa lipida u hemolimfi i masnom telu nedijapauzirajućih i dijapauzirajućih gusenica; da se utvrde promene sastava masnih kiselina strukturne (polarne) i rezervne (nepolarne) frakcije lipida celih gusenica tokom dijapauze i pod uticajem različitih temperatura u eksperimentalnim uslovima; kao i da se odredi tkivna specifičnost, hemolimfe i masnog tela, masnih kiselina ukupnih lipida i biofizičke osobine ukupnih lipida masnog tela nedijapauzirajućih i dijapauzirajućih gusenica tokom dijapauze, kao i u kontrolisanim uslovima hlađenja dijapauzirajućih gusenica. </p><p>U analizi lipida kukuruznog plamenca <em>Ostrinia nubilalis</em>, Hbn. korišćene su sledeće tehnike: tankoslojna hromatografija (TLC) sa skenirajućom denzitometrijom, za razdvajanje i analizu klasa lipida; zatim gasno-masena hromatografija (GC-MS), za analizu masnih kiselina kao i diferencijalna skenirajuća kalorimetrija (DSC – differential scanning calorimetry, eng.), za termalnu analizu ekstrahovanih lipida.</p><p>Kod gusenica <em>Ostrinia nubilalis</em> sastav masnih kiselina ukupnih lipida analiziranih tkiva i lipidnih frakcija značajno se razlikuje između ova dva fiziološka stanja, stanja dijapauze i nedijapauze. Dijapauza indukuje značajno povećanje sadržaja mononezasićenih masnih kiselina, pre svega palmitoleinske (16:1n-7) i oleinske masne kiseline (18:1n-9) uz istovremeno smanjenje sadržaja zasićenih i polinezasićenih masnih kiselina, pre svega palmitinske (16:0) i linolne masne kiseline (18:2n-6). Temperature faznog prelaza ukupnih lipida celih gusenica i masnog tela značajno su niže kod dijapauzirajućih gusenica <em>O. nubilalis</em>, usled značajnog povećanja stepena nezasićenosti masnih kiselina u njihovom sastavu. Značajno niže temperature faznog prelaza lipida dijapauzirajućih gusenica <em>O.<br />nubilalis</em> rezultat su povećanja stepena nezasićenosti njihovih masnih kiselina. Možemo zaključiti da su promene u sastavu masnih kiselina lipida indukovane dijapauzom važna komponenta preživljavanja niskih temperatura kod <em>O. nubilalis</em> Hbn. jer se veliki deo lipida održava u tečnom stanju čak i na temperaturama daleko ispod 0°C, što je neophodno za održavanje njihove fluidnosti odnosno funkcionalnosti.</p> / <p>European corn borer (<em>Ostrinia nubilalis</em>, Hbn.) inhabiting temperate regions that survive low winter temperatures as a diapausing fifth instar larva. Diapausing larvae are cold hardy and freeze tolerant as they are able to survive the extracellular formation of ice crystals. Winter survival for many insect species living in seasonally cold environments includes a radical remodeling of metabolism. This implies entry into a developmentally arrested, hypometabolic state of winter diapause, which in <em>O. nubilalis</em> and many other insect species of these habitats is closely related to their cold hardiness.</p><p>Although the basic structural and metabolic events consider insect diapause is already known, there are still many doubts about the survival of insects in an unfavorable environment, particularly in terms of exposure to low winter temperatures and mechanisms of cryoprotection. Therefore, the aim of this thesis in terms of biophysical properties of lipids and fatty acid compositions, was to: i) to determine the biophysical properties (phase transition temperatures) of the total lipids of non-diapausing larvae and diapausing larvae during diapause (early diapause, mid diapause and termination of diapause), as well as under controlled cooling conditions during different phases of diapause; ii) to determine the fatty acid compositions of structural (polar) and storage (non-polar) total lipid fractions of non-diapausing larvae and diapausing larvae, as well as under the influence of different <br />temperatures during diapause in the controled experimental conditions; iii) to determine the lipid classes composition of total lipids extracted from the haemolymph and fat body of non-diapausing and diapausing larvae; iiii) to determine the haemolymph and fat body total lipid fatty acid compositions as well as the biophysical properties of the fat body total lipids of non-diapausing larvae and diapausing larvae during diapause as well as in terms of controlled cooling conditions. Thus, our research was focused on the non-diapausing (ND) as well as the diapausing larvae (D) that were exposed to low temperatures during different phases of diapause.</p><p>During analysis of European corn borer <em>O. nubilalis</em> lipids, the following techniques was used: thin layer chromatography (TLC) with scanning densitometry, for the separation and quantification of lipid classes; gas-mass chromatography (GC-MS ) for the analysis of the fatty acid composition of lipids and the differential scanning calorimetry (DSC), for the thermal analysis of the extracted lipids.</p><p>The fatty acid compositions and biophysical properties of lipids differed markedly between non-diapausing and diapausing larvae of <em>O. nubilalis</em>. Diapause was associated with a dramatic increase mainly the proportions of palmitoleic acid (16:1n-7) and oleic acid (18:1n-9), with concurrent reductions in palmitic acid (16:0) and linoleic acid (18:2n-6). The increase in the level of unsaturation of lipids, which caused a marked shift in their phase transitions to lower temperatures, was triggered by diapause rather than low temperatures. Adjustments of fatty acid compositions are likely to be an important component of winter diapause mechaisms, possibly maintaining the fluidity of cell membranes, and the functionality of the organism during lower winter temperatures. We conclude that <em>O. nubilalis </em>undergoes remodeling of fatty acid profiles of lipids as an element of its overwintering physiology which may improve the ability to harden during diapause.</p>
|
9 |
Fizičko-hemijska i reološka karakterizacija mikrokapsula ribljeg ulja inkorporiranih u čokoladni matriks / Physico-chemical and rheological characterization of fish oil microcapsules incorporated in a chocolate matrixKalić Marina 31 July 2020 (has links)
<p>Omega-3 masne kiseline su uslovne za zdravlje ljudi i imaju značajne fiziološke uloge. Dijetetski proizvodi na bazi omega-3 masnih kiselina predstavljaju značajan izvor omega-3 masnih kiselina. Riblje ulje je dobar izvor polinezasićenih masnih kiselina (PUFA). Dnevni unos omega-3 polinezasićenih masnih kiselina je u većini delova sveta ispod preporučenog, uglavnom usled nedovoljne zastupljenosti ribe u ishrani. Zbog toga se danas riblje ulje nalazi u obliku različitih dijetetskih proizvoda i ponuda ovih preparata na tržištu je veoma široka. Problem sa unosom ribljeg ulja kao dodatka ishrani je njegov intenzivan i neprijatan ukus i miris, što može da dovede do neadekvatne suplementacije. Sušenje raspršivanjem (engl. spray drying) predstavlja tehniku koja omogućava trenutno sušenje rastvora, suspenzija ili emulzija. U pitanju je metoda koja ima široku primenu u farmaceutskoj industriji, a između ostalog se primenjuje i u cilju maskiranja neprijatnog ukusa lekova. Kao omotač mikrokapsula dobijenih sušenjem raspršivanjem je moguće koristiti proteine, ali je neophodno dobro ispitati i poznavati njihove fizičko-hemijske osobine i funkcionalnost. Inkorporiranjem mikrokapsula ribljeg ulja u čokoladu bi se dobila funkcionalna ili obogaćena hrana, što predstavlja i finalnu formulaciju u ovom radu. Obogaćivanjem čokolade sa visokim sadržajem kakao delova mikrokapsulama ribljeg ulja kreirao bi se višestruko funkcionalan proizvod. Odabir čokolade kao matriksa za obogaćivanje uslovljen je činjenicom da je ona široko konzumiran proizvod. Ciljevi ovog rada bili su da se ispita uticaj metode sušenja raspršivanjem na stabilnost preformulacije ribljeg ulja, da se utvrde karakteristike mikrokapsula dobijenih sušenjem raspršivanjem (prinos i efikasnost mikrokapsulacije, oksidativnu stabilnost ulja, morfološke osobine i veličinu mikrokapsula), zatim da se utvrdi uticaj veličine čestica na kristalizaciju u masnoj fazi suspenzije koja se koristi za izradu konditorskih proizvoda i da se utvrde fizičko-hemijske karakteristike (teksturu, boju, reološke osobine) čokolade koja sadrži inkorporirane mikrokapsule ribljeg ulja u odnosu na čokoladu bez dodatka mikrokapsula. Metode su obuhvatale karakterizaciju proteina dobijenih iz soje, graška, krompira, pirinča i surutke, njihovih rastvora, kao i emulzija ribljeg ulja u vodenim rastvorima tih proteina, određivanje prinosa i efikasnosti mikrokapsulacije i karakterizaciju dobijenih mikrokapsula. Prilikom ispitivanja uticaja veličine čestica na kristalizaciju u masnoj fazi suspenzije koja se koristi za izradu konditorskih proizvoda i fizičko-hemijskih osobina čokolade koja sadrži inkorporirane mikrokapsule ribljeg ulja primenjivane su metode za određivanje teksture, reoloških karakteristika, sadržaja čvrstih masti i boje dobijenih formulacija. Dobijeni rezultati su pokazali da se proteini ponašaju kao dobri emulgatori i da sušenje raspršivanjem predstavlja efikasan način za dobijanje mikrokapsula ribljeg ulja sa proteinima kao omotačima mikrokapsula. Kristalizacija masne faze u suspenziji koja predstavlja model čokolade zavisi od veličine čvrstih čestica. Kada je u pitanju proizvodnja čokolade sa inkorporiranim mikrokapsulama ribljeg ulja kod kojih su kao omotači korišćeni proteini soje, surutke i krompira, dodatak tih mikrokapsula ne utiče na karakteristike čokolade u meri dovoljnoj da bi se narušio proizvodni proces izrade. Sve navedeno upućuje na zaključak da bi proizvodnja čokolade sa inkorporiranim mikrokapsulama ribljeg ulja, tehnološki bila moguća.</p> / <p>Omega-3 fatty acids are essential for human health and have significant physiological roles. Dietary products based on omega-3 fatty acids are a significant source of omega-3 fatty acids. Fish oil is a good source of polyunsaturated fatty acids (PUFA). The daily intake of omega-3 polyunsaturated fatty acids is below the recommended level in most parts of the world, mainly due to the lack of fish in the diet. This is why fish oil is now found as various dietary products which are widely present in the world’s market. The problem with fish oil intake as a dietary supplement is its intense and unpleasant taste and odor, which can lead to inadequate supplementation. Spray drying is a technique that allows instantaneous drying of solutions, suspensions or emulsions. It is a widely used method in the pharmaceutical industry and is used, among other things, to mask the unpleasant taste of medicines. It is possible to use proteins as a coating of spray-dried microcapsules, but it is necessary to test and know their physicochemical properties and functionality. Incorporating fish oil microcapsules into chocolate would make functional or enriched foods, which is consider as a final formulation in this work. Enriching the high cocoa content chocolate with fish oil microcapsules would create a multi-functional product. The choice of chocolate as a base is conditioned by the fact that it is a widely consumed product. The aim of this study was to investigate the effect of spray drying method on the stability of fish oil pre-formulation, to determine the characteristics of microcapsules obtained by spray drying (yield and efficiency of microencapsulation, oxidative stability of oil, morphological properties and size of microcapsules), to determine the effect of particle size crystallization in the oil phase of the suspension used for confectionery products and to determine the physicochemical characteristics (texture, color, rheological properties) of chocolate containing fish oil microcapsules in comparison with chocolate without the addition of microcapsules. Methods included characterization of proteins obtained from soybeans, peas, potatoes, rice and whey, their solutions, as well as fish oil emulsions in aqueous solutions of these proteins, determination of the yield and efficiency of microencapsulation, and characterization of the microcapsules obtained. In the examination of the effect of particle size on crystallization in the oil phase of the suspension used for the manufacture of confectionery and physicochemical properties of chocolate containing fish oil microcapsules, methods were used to determine the texture, rheological characteristics, solid fat content and color of the formulations obtained. The results show that proteins act as good emulsifiers and that spray drying is an effective way to obtain fish oil microcapsules with proteins as microcapsule shells. The crystallization of the oil phase in the suspension representing the chocolate model depends on the size of the solid particles. In the case of production of chocolate with incorporated fish oil microcapsules using soybean, whey and potato proteins as coating material, the addition of these microcapsules does not affect the chocolate characteristics to a degree sufficient to impair the manufacturing process. All of the above points to the conclusion that the production of chocolate with incorporated fish oil microcapsules would be technologically possible.</p>
|
10 |
Odnos između pojedinih markera aterosklerotske bolesti i debljine intima-medija kompleksa karotidne arterije kod bolesnika sa metaboličkim sindromom / Relationship between individual markers of atherosclerotic disease and carotid intima-media thickness of carotid artery in the patients with metabolic syndromeEremić Kojić Nevena 09 July 2019 (has links)
<p>S obzirom na visoku prevalencu metaboličkog sindroma (10-40% u svetskoj populaciji) i na činjenicu da prisustvo metaboličkog sindroma duplira rizik od nastanka aterosklerotske bolesti kardiovaskularnog sistema jasna je potreba za identifikacijom indivudualnih parametara koji doprinose njenom razvoju. Metabolički sindrom je klaster faktora rizika metaboličkog porekla koji je udružen sa povećanim rizikom za nastanak aterosklerotske bolesti kardiovaskularnog sistema i dijabetes melitusa tipa 2. Insulinska rezistencija, abdominalna gojaznost, aterogena dislipidemija, hipertenzija, proinflamatorno i protrombotično stanje su faktori koji su u osnovi metaboličkog sindroma a često su i praćeni nagomilavanjem masti u jetri. Cilj rada je bio da se utvrdi odnos između markera disfunkcije hepatocita (AST, ALT, GGT), serumskog nivoa inflamatornih biomarkera (broj leukocita, elektroforeza serumskih proteina, CRP, fibrinogen, TNF-α), biomarkera endotelne disfunkcije (ADMA i homocistein), kao i nivoa serumskih adipokina (leptin i adiponektin) i debljine intima-medija kompleksa (IMT) karotidne arterije kao pokazatelja prisustva aterosklerotskog procesa. Ispitivanje je dizajnirano kao studija preseka. U ispitivanje je uključeno 58 ispitanika oba pola sa karakteristikama metaboličkom sindroma (NCEP:ATP III kriterijumi). Odabir ispitanika je vršen u Odeljenju za pravilnu ishranu i zdravstvenu bezbednost hrane, Instituta za javno zdravlje Vojvodine. Kontrolnu grupu su sačinjavale 30 klinički i biohemijski zdravih ispitanika nepušača koji su prema polnoj i dobnoj strukturi odgovarali ispitivanim grupama bolesnika. Iz ispitivanja su isključene osobe koje konzumiraju više od 20g/dan alkohola, pušači, koji imaju dijagnostikovan virusni hepatitis B ili C ili pozitivan Hbs antigen, anti-Hbs antitela i anti-HCV antitela, osobe koje imaju verifikovana oboljenja kardiovaskularnog sistema, bubrega, CNS-a, infektivna, maligna i autoimuna oboljenja kao i druga oboljenja jetre i žučnih puteva, osobe koje su pod medikamentoznom terapijom koja može uticati na nivo serumskih biomarkera endotelne disfunckije, lipidni i lipoproteinski status, glikoregulaciju kao i menstruacioni ciklus. Sve laboratorijske analize su urađene u Centru za laboratorijsku medicinu, Kliničkog centra Vojvodine. Doppler ultrasonografski pregled karotidnih arterija i ultrazvuk abdomena i jetre je urađen u Centru za radiologiju Kliničkog centra Vojvodine. Signifikantna pozitivna korelacija niskog stepena je utvrđena između IMT zajedničke karotidne arterije i serumskih koncentracija GGT, hsCRP i leptina kao i odnosa neutrofili/limfociti. Prema prvom konstruisanom regresionom modelu u kojem je zavisna varijabla bila IMT preko 0,09 cm statistički značajan uticaj na predviđanje debljine IMT zajedničke karotidne arterije imaju hsCRP (Exp (B) 1,112 i glikemija (Exp (B) 1,973). Prema modelu neuronske mreže sa istom zavisnom varijablom najveću mogućnost predviđanja IMT imaju glikemija, AST i fibrinogen. Prema drugom konstruisanom regresionom modelu gde su zavisne varijable bile IMT zajedničke karotidne arterije preko 0,09 cm i prisutnost hepatične steatoze najveću mogućnost predviđanja imaju leptin Exp (B) 1,1022 i ALT Exp (B) 1,053. Prema modelu neuronske mreže sa istom zavisnom varijablom najveću mogućnost predviđanja IMT imaju ALT, ADMA i leptin.</p> / <p>Given the high prevalence of metabolic syndrome (10-40% in the world population) and the fact that the presence of metabolic syndrome doubles the risk of atherosclerotic disease of the cardiovascular system, there is a clear need to identify individual parameters that contribute to its development. Metabolic syndrome is a cluster of the risk factors of metabolic origin that is associated with an increased risk for the onset of atherosclerotic disease of the cardiovascular system and type 2 diabetes mellitus. Insulin resistance, abdominal obesity, atherogenic dyslipidemia, hypertension, proinflammatory and prothrombotic conditions are the factors at the base of the metabolic syndrome and are often accompanied by fat accumulation in the liver. The aim of this work was to determine the relation between markers of hepatic dysfunction (AST, ALT and GGT), serum levels of inflammatory biomarkers (white blood cell count, electrophoresis of serum proteins, CRP, fibrinogen, TNF-α), biomarkers of endothelial dysfunction (ADMA and homocysteine) as well as levels of serum adipokines (leptin and adiponectin) and intima-media thickness of carotid artery as indicators of atherosclerotic process in the patients with metabolic syndrome. Study was cross-sectional. It included 58 participants with metabolic syndrome (NCEP:ATP III criteria) as well as 30 clinically and biochemically healthy nonsmokers, age and gender matched controls. Participants were selected in the Department for Nutrition and Food Safety, Center of Hygiene and Human Ecology Institute of Public Health of Vojvodina. Patients that consumed alcohol more than 20g/day were excluded. Participants with positive HBsAg, anti-HBs-antibodies or anti- HCV antibodies were excluded also. Smokers were also excluded. Patients with cardiovascular diseases, renal diseases, infective, hepatic, malignant and autoimmune diseases were excluded from this study. Subjects which used drugs that could affect biomarker levels of endothelial dysfunction, lipid metabolism, glucose metabolism and menstrual cycle were also excluded. All laboratory analyzes were done in Centre for Laboratory Medicine, Clinical Centre of Vojvodina. Doppler ultrasonography of carotid arteries and ultrasound of abdomen and liver were done in Centre for Radiology, Clinical Centre of Vojvodina. Significant positive correlation of low degree was determined between IMT of common carotid artery and serum concentrations between GGT, hsCRP and leptin and relationship neutrophils/lymphocytes. According to the first constructed regression model where dependent variable was IMT of common carotid artery above 0.09 cm statistically significant influence on foreseeing IMT of common carotid artery have hsCRP (Exp (B) 1.112 and glycaemia (Exp (B) 1.973). According to the neuronal network with the same dependent variable greatest probability for foreseeing IMT have glycaemia, AST and fibrinogen. According to the second constructed regression model where dependent variable was IMT above 0.09 cm and present hepatic steatosis greatest probability for foreseeing IMT have leptin Exp (B) 1.1022 and ALT Exp (B) 1.053. According to the neuronal network with the same dependent variable greatest probability for foreseeing IMT have ALT, ADMA and leptin.</p>
|
Page generated in 0.0433 seconds