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1

Olga, Govedarica. "Određivanje optimalnih uslova izvođenja procesa epoksidovanja biljnih ulja persirćetnom kiselinom". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2017. http://www.cris.uns.ac.rs/record.jsf?recordId=104159&source=NDLTD&language=en.

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Abstract (sommario):
Hemijskim transformacijama se iz biljnih ulja dobijaju vredni                                         derivati, poput epoksidovanih biljnih ulja, koji sekoriste u hemijskoj i polimernoj industriji. Kvalitet, patime i primena epoksidovanih biljnih ulja, zavise odsadržaja epoksidnih grupa u derivatizovanom ulju, koji bitrebalo da je što veći. Kako epoksidne grupe nastajuoksidacijom dvostrukih veza u trigliceridima kaodominantnoj grupi jedinjenja u biljnim uljima, pogodnasirovina za epoksidovanje su visoko nezasićena ulja,kakvo je laneno.Proizvodnja epoksidovanih biljnih ulja zahteva izbortakvih procesnih uslova pri kojima bi se postigli štopotpunija konverzija dvostrukih veza i što većaselektivnost procesa u odnosu na epoksidnu grupu. Zato jekao cilj ove doktorske disertacije postavljeno određivanjeoptimalnih vrednosti procesnih uslova epoksidovanjalanenog ulja persirćetnom kiselinom formiranom in situ izsirćetne kiseline i 30% vodenog rastvora vodonikperoksida u prisustvu jonoizmenjivačke smole kaokatalizatora. Određivanje je izvedeno primenommetodologije odzivne površine, kao i korišćenjem u ovojdisertaciji predloženih kinetičkih modela ispitivanogreakcionog sistema, u oba slučaja sa maksimumomrelativnog prinosa epoksida kao funkcijom cilja.Ispitivanje uticaja procesnih uslova, i to temperature,molskog odnosa reaktanata, količine katalizatora i brzinemešanja, na tok procesa epoksidovanja je bilo osnov zadefinisanje graničnih vrednosti procesnih uslova unutarkojih je tražen maksimum prinosa epoksida. Oblast dugihvremena reagovanja, koja nije od interesa za industriju, jeizbegnuta adekvatnim izborom temperature.Pri optimalnim vrednostima procesnih uslovaepoksidovanja lanenog ulja, određenim primenommetodologije odzivne površine, postignuto je dobroslaganje očekivane i eksperimentalno određene vrednostimaksimalnog relativnog prinosa epoksida, sa odstupanjemod 3,28%.Za potrebe određivanja optimalnih uslova izvođenjaprocesa epoksidovanja biljnih ulja korišćenjem kinetičkihmodela, razvijena su tri pseudohomogena modelaispitivanog trofaznog multireakcionog sistema. Poredkinetike osnovnih reakcija formiranja persirćetne kiseline i                                     reakcije epoksidovanja dvostrukih veza triglicerida biljnog ulja,                                       kao i kinetike sporedne reakcije otvaranja epoksidnegrupe sa sirćetnom kiselinom, u predloženim modelima jeuzeta u obzir i raspodela sirćetne i persirćetne kiselineizmeđu uljne i vodene faze sistema. Opisan je i uticajmasno-kiselinskog sastava ulja, odnosno broja dvostrukihveza u masno-kiselinskim lancima triglicerida, na kinetikureakcija. Za koeficijent raspodele sirćetne kiseline izmeđutečnih faza reakcionog sistema predložena je empirijskakorelacija koja je dala dobro slaganje izračunatihvrednosti sa eksperimentalnim podacima. Kinetičkiparametri modela su određeni fitovanjemeksperimentalnih podataka o promenama količinadvostruke veze i epoksidne grupe sa vremenom izvođenjaprocesa epoksidovanja. Na osnovu statističkih pokazateljauspešnosti fitovanja eksperimentalnih podataka, potvrđenaje prepostavka da je pseudohomogeni model publikovan uliteraturi unapređen uzimanjem u obzir pomenutihfenomena raspodele komponenata reakcione smeše imasno-kiselinskog sastava sirovine pri modelovanjureakcionog sistema epoksidovanja biljnih uljapersirćetnom kiselinom.Korišćenjem predloženih pseudohomogenih modelareakcionog sistema za određivanje optimalnih uslovaizvođenja procesa epoksidovanja lanenog ulja in situformiranom persirćetnom kiselinom u prisustvujonoizmenjivačke smole, dobijeno je odstupanje od 5,51%očekivane od eksperimentalno određene vrednostirelativnog prinosa epoksida.Bolje slaganje predviđene sa eksperimentalno određenomvrednošću relativnog prinosa epoksida u kontrolnomeksperimentu je dobijeno primenom metodologije odzivnepovršine u poređenju sa korišćenjem kinetičkih modela priodređivanju optimalnih vrednosti procesnih uslova. To je iočekivano, s obzirom da regresiona jednačina korišćena uokviru metodologije odzivne površine bolje fituje relativniprinos epoksida. Standardna devijacija relativnog prinosepoksida za regresionu jednačinu je 8,9 puta niža od oneizračunate za kinetički model koji najbolje predviđaoptimalne procesne uslove epoksidovanja lanenog uljapersirćetnom kiselinom.
Vegetable oils can be transformed into added valueproducts by various chemical modifications, such asepoxidation. The epoxidized vegetable oils have awide range of applications in the chemical andpolymer industry. The quality, and consequently theapplication, of epoxidized vegetable oil is influencedby the epoxy group content. Since the epoxy groupsare formed by the oxidation of double bonds intriglycerides, the main constituent of vegetable oils,highly unsaturated vegetable oils, such as linseedoil, are desirable raw materials.The manufacturing of epoxidized vegetable oilsrequires the optimization of the process conditionsin order to achieve complete conversion of doublebonds and high selectivity of the process in respectto the epoxy groups. Therefore, the aim of thisdoctoral thesis is to determine the optimal processconditions for the epoxidation of linseed oil withperacetic acid, formed in situ from acetic acid and30% hydrogen peroxide in the presence of an ionexchange resin as the catalyst. The optimal processconditions were determined by response surfacemethodology, as well as by using developed pseudohomogeneouskinetic models that describe theinvestigated reaction system. For both optimizationmethods, the relative epoxy yield was selected as anobjective function to be maximized.The effects of process conditions, such astemperature, molar ratio of reactants, catalystamount and steering speed, on the kinetics of theepoxidation were studied in order to defineconstraints for the optimization. To avoid longreaction times, which are not of interest inmanufacturing, an adequate temperature range wasselected. Under the optimized process conditions for theepoxidation of linseed oil, which were determinedby response surface methodology, good agreementbetween the calculated and experimentallydetermined relative epoxy yields was achievedwithin 3.28%.Three models describing the three-phase multireactionsystem of vegetable oil epoxidation withperacetic acid were developed and further used forthe optimization. The models are pseudohomogeneouswith respect to the catalyst. Besidesthe kinetics of the main reactions of peracetic acidand epoxy group formation, the models take intoaccount the side reaction of the epoxy group openingwith acetic acid. The partitioning of the acetic acidand peracetic acid between the oil and aqueousphases is considered. In two proposed models, theeffect of fatty acid composition on the kinetics of theprocess is also described by considering the numberof double bonds in the fatty acid chains. Thedeveloped empirical correlation for the partitioncoefficient for acetic acid between the liquid phasesshows good agreement between the calculated andexperimental data. The kinetic parameters of theproposed pseudo-homogeneous models weredetermined by fitting the experimentally determinedchanges of the double bond and epoxy groupamounts with reaction time of the epoxidation.Statistical values of the models` parametersdetermination confirmed the hypothesis that thepseudo-homogeneous model proposed in theliterature can be improved by considering thepartitioning phenomena and the effect of the oil fattyacid composition on the kinetics of the vegetableoils epoxidation with peracetic acid.Under the optimized process conditions for theepoxidation of linseed oil with peracetic acid formedin situ in the presence of the ion exchange resin,which were determined by using proposed pseudohomogeneousmodels, the experimentallydetermined relative epoxy yield was 5.51% lowerthan the calculated.Better agreement between the calculated andexperimentally determined values for the relativeepoxy yield, achieved under the optimal processconditions, is obtained when the response surfacemethodology (RSM) was applied as opposed towhen the kinetic models were used for thedetermination of the optimal process conditions.This is in accordance with better fitting of therelative epoxy yield by RSM regression equationthan by kinetics models. Standard deviation of therelative epoxy yield for RSM regression equation is 8.9 times lower than the standard deviation for themost successful kinetic model used for prediction ofthe optimal process conditions for the epoxidation ofthe linseed oil by peracetic acid.
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2

Dragiša, Đorđić. "Revitalizacija i sagorevanje otpadnih transformatorskih i motornih ulja u funkciji zaštite životne sredine". Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2020. https://www.cris.uns.ac.rs/record.jsf?recordId=112424&source=NDLTD&language=en.

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Abstract (sommario):
U doktorskoj disertaciji je realizovano ispitivanje revitalizacije, parametara sagorevanja i emisije otpadnih transformatorskih i motornih ulja, kao i njihovih dizel mešavina. Dobijeni eksperimentalni rezultati ukazuju da se nakon revitalizacionog tretmana značajno poboljšavaju izolaciona svojstva transformatorskog ulja, što je veoma važno za bezbedan rad transformatora, zaštitu životne i radne sredine. Pored toga, rezultati eksperimentalnog ispitivanja procesa sagorevanja ukazuju da se otpadna transformatorska i motorna ulja i njihove mešavine sa dizelom mogu koristiti kao gorivo u generatorima toplote male snage i u raznim granama procesne industrije, te mogu smanjiti probleme u vezi sa zaštitom životne sredine.
The doctoral thesis cover the testing of revitalization, combustion parameters and emissions of waste transformer and motor oils, as well as their diesel mixtures. The experimental results obtained indicate that after the revitalization treatment, the insulating properties of the transformer oil are significantly improved, which is very important for the safe operation of transformer, environmental protection and work environment. In addition, the results of an experimental test of the combustion process indicate that waste transformer and motor oils and their mixtures with diesel can be used as fuel in low power heat generators and in various branches of the process industry, and can reduce environmental issues.
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3

Zoran, Zeković. "Ekstrakcija timijana (Thymus vulgaris L.) superkritičnim ugljendioksidom". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 1999. https://www.cris.uns.ac.rs/record.jsf?recordId=71448&source=NDLTD&language=en.

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Abstract (sommario):
Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).Ispitana je ekstrakcija timijana (Thymus vulgaris L.) primenom ugljendioksida u superkritičnom stanju kao ekstragensa. Razrađen je postupak tečne hromatografije pod visokim pritiskom (HPLC) za određivanje farmakološki aktivnih fenolnih jedinjenja, timola i karvakrola, koji obezbeđuje visok stepen reproduktivnosti određivanja (za timol Kw = 1,29%). Za kvalitativnu i kvantitativnu analizu proizvoda na bazi timijana, etarskog ulja i ekstrakata, primenjen je metod gasne hromatografije (GC) sa masenom spektrometrijom (MS). Sadržaj etarskog ulja određen oficinalnim postupkom koji propisuje jugoslovenska farmakopeja iznosi 1,75% (V/m). Dominantna komponenta etarskog ulja timijana je timol čiji je sadržaj 50,06% (m/m), dok je karvakrol prisutan, praktično, u tragovima (1,15%). Od prisutnih parafina u etarskom ulju, največi sadržaj ima n-tetradekan (16,11%). U totalnom ekstraktu timijana dobijenom metilen- hloridom primenom ekstrakcije sa povremenim ispuštanjem ekstrakta (Ekstrakcija po Soxhlet-u), koji je dobijen u prinosu 4,95% (m/m), dominantna komponenta je n-tetradekan (47,18%), dok je sadržaj timola 16,11%.Kinetika ekstrakcije timola se može uspešno predstaviti analogno izrazu za kinetiku reakcije prvog reda, primenom koje se dobija največa vrednost konstante brzine ekstrakcije (k) 0,2209 h-1 za selektovani protok superkritičnog ugijendioksida 97,725 dm3/h.Primenom timijana stepena usitnjenosti d2 srednjeg prečnika 0,35 mm za ekstrakciju superkritičnim ugijendioksidom (100 bar; 40°C; 2,5 sata) postiže se kvantitativna ekstrakcije prisutnog etarskog ulja. Po svom sastavu ovaj ekstrakt je najsličniji etarskom ulju timijana dobijenom destliacijom pomoću vodene pare. Produžavanje vremena ekstrakcije iznad 2,5 sata ima za posledicu povećani prinos, pre svega, parafina.Primenom ugljendioksida male moći rastvaranja (80 bar; 400C;  d=0,1918 g/cm3) ne postiže se kvantitativna ekstrakcija etarskog ulja. Povećavanjem radnog pritiska od 100 do 400 bar, usled povećanja moći rastvaranja, dobijaju se ekstrakti koji su po svom sastavu sve sličniji totalnom ekstraktu dobijenom ekstrakcijom metilenhloridom.Za modelovanje ekstrakcionog sistema timijan - superkritični ugljendioksid je primenjena jednačina Reverchon-a i Sesti Osseo-a:                                         Y = 100 [1-exp(-t/ti)]gde je: Y - normalizovani ekstrakcioni prinos (%); t - vreme ekstrakcije (s) i ti -       vreme unutrašnje difuzije (s)odnosno njen modifikovani oblik:                                        Y = 100 [1 - ehr (at + b)]Izračunate vrednosti standardne greške regresije (SY,X) ukazuju da u osnovi modifikovana jednačina bolje fituje normalizovane prinose kako totalnog ekstrakta, tako i timola, u odnosu na polaznu jednačinu.Jednačine:   log S = a mrel + bi   log S = a dC02 + bgde je: S - rastvorljivost totalnog ekstrakta (g/dm3), odnosno timola (mg/dm ) u ugljendioksidu; mrel - relativna masa ugljendioksida (g CO2/g timijana) i dCO2 zapreminska masa ugljendioksida (g/cm3)se mogu, takođe, uspešno primeniti za modelovanje ekstrakcije ispitivanog sistema.Primenom ugljendioksida u tečnom stanju (65 bar; 23°C) se dobija ekstrakt timijana sličan po svom sastavu ekstraktu dobijenom ekstrakcijom superkritičnim ekstragensom na pritisku 100 bar.U cilju dobijanja ekstrakta timijana koji je po svom kvalitativnom i kvantitativnom sastavu najsličniji etarskom ulju dobijenom oficinalnim postupkom destilacije pomoću vodene pare, neophodno je za ekstrakciju koristiti ugljendioksid zapreminske mase 0,6302 g/cm3( 100 bar;40°C), biljni materijal stepena usitnjenosti d2, vreme ekstrakcije 2,5 sata i protok ekstragensa 97,725 dm3/h.
Abstract was processed by technology for Optical character recognition (OCR).The extraction of thyme (Thymus vulgaris L.) by supercritical carbon dioxide as an extragent was investigated. The developed HPLC (High Pressure Liquid Chromatography) method for determination of pharmacologically active phenolic compounds, thymol and carvacrol, showed a high reproducibility (Kw for thymol 1.29%). Qualitative and quantitative analyses of thyme products, essential oil and extracts, were carried out by gas chromatography - mass spectrometry (GC-MS). The content of essential oil determined by an official procedure given by Yugoslav pharmacopoeia was 1.75% (V/w). The predominant compound of the essential oil is thymol (50.06%; w/w), while carvacrol is present, practically, in traces (1.15%; w/w). The content of n-tetradecane in the thyme essential oil (16.11%; w/w) is higher than that of other paraffins. In the total thyme extract obtained by methylene chloride using extraction with periodical exchange of the extract (Soxhlet extraction) in a yield of 4.95%(w/w), the predominant compound was n-tetradecane (47.18%), while the content of thymol was 16.11%.The extraction kinetic of thymol can be successfully expressed by analogy to first order reaction kinetic, and a highest value of extraction rate constant (k) of 0.2209 h-1 for the selected flow rate of supercritical carbon dioxide of 97.725 dm3/h.A quantitative extraction of thyme essential oil by supercritical carbon dioxide (100 bar; 40°C; 2.5hours) was obtained using thyme of the grinding degree d2 (mean particle diameter 0.35 mm). The composition of this extract is very similar to that of the essential oil obtained by steam distillation. A higher yield of extraction, primarily of paraffins, was obtained by prolonging the extraction time over 2.5 hours. The use of carbon dioxide of low solubility power (80 bar; 400C; d =0.1918 g/cm3) did not yield a quantitative extraction of thyme essential oil.Ву increasing extraction pressure from 100 to 400 bar, i.e. solubility power, the extract composition was more and more similar to the composition of total extract obtained by methylene chloride.То model extraction of the system thyme - supercritical carbon dioxide use was made of the Reverchon - Sesti Osseo equation:                  Y = 100 [1-exp(-t/ti)]where: Y - normalized extraction yield (%); t - extraction time (s) and ti - internal diffusion time (s)i.e. of its modified form:                 Y = 100 [1 - ехр (at + b)]The calculated values of standard error of regression (SY,X) show that the modified equation is generally a better fit for the normalized yields of total extract and thymol compared to the original equation.Equations:        log S = a mrel + band         log S = a dC02 + bwhere: S - solubility of total extract (g/dm3), i.e. of thymol (mg/dm3) in carbon dioxide; mrel - relative mass of carbon dioxide (g CO2/g thyme) and dCO2 carbon dioxide density (g/cm3)could be successfully used for modelling of the investigated extraction system.The composition of thyme extract obtained by liquid carbon dioxide (65 bar; 23°C ) is very similar to that obtained by supercritical extragent at a pressure of 100 bar.То obtain a thyme extract whose qualitative and quantitative characteristics are most similar to those of the essential oil obtained using official procedure by steam distillation, it is necessary to use a carbon dioxide density of 0.6302 g/cm3 (100 bar; 400C), grinding degree of thyme d2, extraction time of 2.5 hours and extragent flow rate of 97.725 dm3/h.
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4

Branislava, Nikolovski. "Kinetika i modelovanje ekstrakcije ulja iz bobica kleke (Juniperus communis L.) i semenki tikve (Cucurbita pepo L.) natkritičnim ugljendioksidom". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2009. https://www.cris.uns.ac.rs/record.jsf?recordId=71281&source=NDLTD&language=en.

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Abstract (sommario):
U radu su prikazani eksperimentalni rezultati natkritične ekstrakcije etarskog ulja bobicakleke (Juniperus communis L.) i ulja iz semena uljane tikve golice (Cucurbita pepo L.). Ispitan je uticaj pritiska, temperature, stepena usitnjenosti čestica i protoka natkritičnogugljendioksida na promenu prinosa ulja sa vremenom. U cilju poređenja, usitnjeno seme uljane tikve ekstrahovano je i u ekstraktoru većih dimenzija, NOVA-SWISS, Highpressure extraction plant, kao i heksanom i petroletrom u ekstraktoru tipa Sokslet.Praćena je i promena kvaliteta ekstrakata sa vremenom: u etarskom ulju kleke, GC-FID i GC-MS metodama, određen je relativni sadržaj 50 terpenskih jedinjenja i sve komponente ulja su svrstane u 5 osnovnih grupa (monoterpene, seskviterpene, oksidovane monoterpene, oksidovane seskviterpene i ostale komponente). U tikvinom ulju ekstrahovanom natkritičnim ugljendioksidom određen je masnokiselinski sastav GC-MS analizom, sadržaj tokoferola HPLC analizom, sterola i skvalena GC-MS metodom. Određeni su uslovi koji favorizuju ekstrakciju ispitanih jedinjenja za obe sirovine. Dat je dateljan prikaz matematičkih modela koji se koriste za opisivanje natkritične ekstrakcije etarskih ulja i masnih ulja, počevši od najopštijeg modela koji uključuje diferencijalne bilanse mase za rastvorak u masi natkritičnog fluida, u fluidu unutar pora čestica usitnjenog matrijala i u čvrstoj fazi, koji se uvođenjem određenih pretpostavki pojednostavljuje i svodi na modele koji su izabrani da budu ispitani u okviru ovoga rada. Ispitani su modeli kreireni po analogiji sa hlađenjem vrele kugle u masi fluida, tj. modeli tipa jedne sfere i to: Model jedne sfere-1 (MJS-1), koji pored uticaja koeficijenta efektivne difuzije ulja u materijalu na brzinu prenosa mase uzima u obzir uticaj koeficijenta prenosa mase kroz film natkritičnog fluida oko čestice, pri čemu je njegova vrednost procenjena preko postojećih korelacija; MJS-1 (2 par), u kome je spoljašnji koeficijent prenosa mase uzet kao drugi prilagodljiv parametar modela; MJS-2, gde je koeficijent efektivne difuzije jedini prilagođeni parametar, Model karakterističnog vremena i prošireni model klipnog toka koji je predložila Sovová. Za modelovanje natkritične ekstrakcije ulja semena tikve korišćen je i kombinovani model Honga i sar. Softverskim paketima Mathcad 2001 Professional i Solver dodatka unutar Microsoft Excel 2003, određeni su parametri ispitanih modela u cilju najboljeg slaganja modela sa ekperimentalnim podacima. Za obe ispitane sirovine, među ispitanim modelima, izabrani su modeli koji najbolje opisuju njihovu ekstrakciju natkritičnim ugljendioksidom. Prošireni model klipnog toka koji je predložila Sovová pokazao se podjednako dobrim za modelovanje natkritične ekstrakcije obe sirovine i nešto bolji od ostalih primenjenih modela.
This study provides results of supercritical carbon dioxide (SCCO2) extraction of juniper berries (Juniperus communis L.) and pumpkin seeds (Cucurbita pepo L. convar. citrullina) in a laboratorysupercritical fluid extraction apparatus. The influenceof pressure, temperature, particle size and carbon dioxide flow on the extraction kinetics of pumpkin seed oil and juniper berry essential oil was studied. Ground pumpkin seeds were also extracted with supercritical carbon dioxide in NOVA-SWISS, High Pressure Extraction Plant, and with hexane and petroleum ether in a laboratory Soxhlet extractor. This work was also aimed to investigate the evolution of the composition of juniper fruit supercritical CO2 extracts with time, at different extraction pressures and to emphasize the most favorable condition for the extraction of different terpene hydrocarbon groups, reporting the qualitative differences among extracts collected during successive extraction time periods. Juniper berry extracts were analyzed by capillary gas chromatography, using flame ionization (GC-FID) and mass spectrometric detection (GC-MS). More than 200 constituents were detected in the extracts and the contents of 50 compounds were reported in the work. Dependence of the percentage yields of monoterpene, sesquiterpene, oxygenated monoterpene and oxygenated sesquiterpene hydrocarbon groups on extraction time was investigated and conditions that favored the yielding of each terpene groups were emphasized. GC-MS analysis of FAME, prepared by transesterification of pumpkin seed oil with KOH in methanol, was performed. Fatty acid compositions of supercritical CO2 pumpkin seed extract fractions collected in successive time intervals over the course of the extraction were determined. The same fractions were analyzed by high pressure liquid chromatography (HPLC), using diode-array detector (DAD) in order to determine a- and g-tocopherol contents. Sterol and squalene contents were determined by GC-MS analysis, as well. Conditions that favored the yielding of tocopherols, squalene and sterols were emphasized. A general mass transfer model and its simlifications were analysed. Extraction curves were evaluated by “hot sphere” mathematical models SSM-1 (Single Sphere Model 1 – in which the external mass transfer coefficient also influences the extraction profile and film mass transfer coefficients were estimated by the correlations), SSM-1 (2 par) (film mass transfer coefficient is used as the second adjustable parameter), SSM-2 (only effective diffusivity influence is considered), Characteristic time model and by the extended Lack’s plug-flow model given by Sovová. A combined model of Hong et al. was also fitted to the experimental data for pumpkin seed oil SCCOextractions. Relative merits of the models are demonstrated. Good agreement between the extended Lack’s plug-flow model and the experimental measurements was obtained.
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5

Whybrew, Linda Christine. "The Relationship between Horace's Sermones and Epistulae Book 1: "Are the Letters of Horace Satires?"". Thesis, University of Canterbury. Classics and Linguistics, 2006. http://hdl.handle.net/10092/945.

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Abstract (sommario):
"Are the Letters of Horace Satires?" (Hendrickson 1897: 313). In response to this question, this thesis investigates whether Horace's Sermones and Epistulae 1 all belong to the genre of satura. Ancient and modern evidence from the use of the terms Sermones, Epistulae, and satura, is surveyed, and is found to be inconclusive, but not to preclude Epist. 1 as satura. The nature of specifically Horatian satura is ascertained from the text of Serm. 1, especially Serm. 1.1 and the explicitly literary Serm. 1.4 and 1.10. The redefinition of Lucilian satura, and its political implications are also considered. To confirm Epist. 1 as satura a sequential reading of the three libelli is undertaken, tracing the evolution of the theme of locus: place, both as geographical location, and as status, place in the social hierarchy, in the context of the socio-political environment of the time of composition. Serm. 1.1 as a programmatic poem is shown to establish Epicurean moderation as a prerequisite for a vita beata. In Serm. 1 Horace's status as client-poet of Maecenas and Octavian initially permits this ideal lifestyle in the Urbs. The misperceptions of outsiders lead to a preference for a life of Epicurean quietude in the rus in Serm. 2, although Horace's aequanimitas is disturbed by urban officia, and abuse of libertas dicendi associated particularly with Stoicism. The ideal of rural withdrawal is reinforced in Epist. 1 through an exploration of appropriate behaviour in relationships with potentes amici. Horace's addressees cover the entire range of the social hierarchy, and in his letters he utilizes the arguments of moral philosophy, thus reconciling poetry and philosophy. He achieves a pragmatic compromise whereby he can enjoy libertas in his role as a poet, while acknowledging that personal libertas and true aequanimitas are still to be attained.
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6

Milovan, Janković. "Matematički model reakcionog sistema za in situ epoksidovanje sojinog ulja persirćetnom kiselinom". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2013. https://www.cris.uns.ac.rs/record.jsf?recordId=83242&source=NDLTD&language=en.

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Abstract (sommario):
Cilj ove doktorske disertacije je postavljanjematematičkog modela složenog trofaznog reakcionogsistem za epoksidovanje sojinog ulja in situ formiranompersirćetnom kiselinom iz sirćetne kiseline i vodonikperoksida u prisustvu jonoizmenjivačke smole kaokatalizatora. Model uzima u obzir koncentracijereaktanata i produkata u vodenoj i uljnoj fazi. Poredosnovnih reakcija stvaranja persirćetne kiseline iepoksida, model obuhvata i sporednu reakciju otvaranjaepoksi prstena sa sirćetnom kiselinom. Za modelovanjereakcije formiranja persirćetne kiseline na površinikatalizatora primenjeni su Langmuir-Hinshelwood-Hougen-Watson i Rideal-Eley postulati. Postavljenitrofazni model predstavlja sistem običnih diferencijalnihjednačina prvog reda koji opisuje promenu broja molovakomponenata i funkcionalnih grupa sa vremenomizvođenja procesa epoksidovanja, i sadrži više parametararazvrstanih na kinetičke, termodinamičke i parametre kojise odnose na prenos mase. Parametri modela zavise oduslova izvođenja epoksidovanja i to svi od temperature, aneki i od sastava i inteziteta mešanja.Za konstantu hemijske ravnoteže reakcije nastajanjapersirćetne kiseline je izvedena semiteorijska zavisnostod temperature koja daje vrednosti istog reda veličine iistog smera promene sa temperaturom kao i većinapodataka objavljenih u literaturi.Za izračunavanje koeficijenta raspodele sirćetne kiselineizmeđu uljne i vodene faze potrebno je odrediti zavisnostkonstante fazne ravnoteže tečno-tečno sirćetne kiseline odsastava i temperature. Utvrđeno je da je UNIFAC modelgrupnih doprinosa za koeficijente aktivnosti nepogodanza predskazivanje ravnoteže tečno-tečno. Eksperimentalnipodaci za ovu konstantu ravnoteže su uspešno korelisaniUNIQUAC modelom za koeficijente aktivnosti.Parametri reparametrizovane Arrheniusove zavisnostikonstanti brzina reakcija i konstanti sorpcije učesnikareakcije stvaranja persirćetne kiseline od temperatureodređeni su simultano sa parametrima koji se odnose naprenos mase i sa odnosom koeficijenata raspodelepersirćetne i sirćetne kiseline između uljne i vodene faze,fitovanjem eksperimentalnih podataka epoksidovanjasojinog ulja, tj. minimizacijom sume kvadrata odstupanjaračunskih od eksperimentalno određenih vrednosti jodnogbroja i sadržaja epoksi kiseonika tokom epoksidovanja.Fitovanje je uspešno izvedeno primenom metodeMarquardta, dok su pomenute računske vrednostidobijene numeričkom integracijom sistemadiferencijalnih jednačina modela primenom Runge-Kuttametode IV reda.
The objective of this doctoral thesis was development ofmathematical model for complex three-phase reactionsystem for soybean oil epoxidation with peracetic acidformed in situ from acetic acid and hydrogen peroxide in apresence of an ion exchange resin as catalyst. The localconcentrations of components in water and oil phases wereintroduced into the model. In addition to reactions of theperacetic acid and epoxy compound formation, modelconsiders the side reaction of epoxy ring cleavage withacetic acid. Approximate modeling of peracetic acidformation was based on Langmuir-Hinshelwood-Hougen-Watson and Rideal-Eley postulates. Established threephasemodel is a system of ordinary first order differentialequations which describes change of components andfunctional groups amounts with reaction time. Besideskinetic parameters, model comprises the thermodynamicones as well as parameters of mass transfer between the oiland water phase. All model parameters are dependent ontemperature and some additionally on composition andintensity of stirring.A semitheoretical temperature dependency of chemicalequilibrium constant for peracetic acid formation wasestablished. The order of magnitude and temperature trendof the calculated chemical equilibrium constant are inagreement with the most data given in a literature.For calculation of partition coefficient for acetic acidbetween oil and water phase, temperature and compositiondependency of liquid-liquid equilibrium constant for aceticacid is necessary. It was found that UNIFAC model ofgroup contribution was non-applicable for the predictionof the equilibrium constant. The experimental data for theequilibrium constant were, however, successfully fitted byUNIQUAC model.Temperature dependencies of the reaction rate constantsand sorption constants of reactants and products inperacetic acid formation reaction are expressed byreparameterized Arrhenius equation. The parameters ofsuch equation were determined simultaneously with masstransfer parameters and ratio of peracetic acid and aceticacid partition coefficients between oil and water phase byfitting the experimental data i.e. by minimization of leastsum of squares of deviation between the calculated andexperimentally determined iodine value and epoxy oxygencontent . Marquardt method was successfully used to fitthe experimental data. A fourth-ordered Runge-Kuttamethod was applied for integrating the system ofdifferential equations of the model.
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7

Predrag, Kukić. "Uticaj ekstrudiranja na promene odabranih fizičko-hemijskih svojstava soje". Phd thesis, Univerzitet u Novom Sadu, Poljoprivredni fakultet u Novom Sadu, 2018. https://www.cris.uns.ac.rs/record.jsf?recordId=104284&source=NDLTD&language=en.

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Abstract (sommario):
Cilj istraživanja je da se utvrde promene hemijskog sastava proizvoda na izlazu iz ekstrudera i prese (sojine pogače i ulja), tj. njihovog kvaliteta sa aspekta njihove dalje primene u proizvodnji stočne hrane, primene u prehrambenoj industriji ili daljoj primeni sojinog ulja u proizvodnji biodizela, a sve u funkcionalnoj zavisnosti od promenljivih karakteristika ulazne sirovine i parametara rada ekstrudera. Ekstrudiranje sojinog zrna vršilo se na ekstruderu tip E751, proizvođača „SREM PRODUKT“ DOO iz Laćarka, a presovanje na presi tip PM-5S proizvođača „BRONTO“ iz Ukrajine. Istraživanja koja su sprovedena u ovoj doktorskoj disertaciji rađena su kao doprinos proširenju znanja vezanih za proces proizvodnje sojine pogače i sojinog ulja, a pored toga  kako bi dobili praktične smernice za optimalnu kontrolu i modelovanje procesa estruzije i ceđenja soje kao i projektovanja ekstrudera. U cilju dobijanja i analiziranja podataka koji bi mogli da utvrde promene hemijskog sastava proizvoda na izlazu iz ekstrudera i prese (sojine pogače i ulja), tj. njihovog kvaliteta sa aspekta njihove dalje primene u proizvodnji stočne hrane, primene u prehrambenoj industriji ili daljoj primeni sojinog ulja u proizvodnji biodizela, a sve u funkcionalnoj zavisnosti od promenljivih karakteristika ulazne sirovine i parametara rada ekstrudera, sprovedena su eksperimentalna i laboratorijska ispitivanja. Eksperimentalna istraživanja su namenjena praktičnoj primeni kojom bi se proces proizvodnje sojine pogače i sojinog ulja mogao usavršiti i optimatizovati. Rezultati koji su dobijeni ovim istraživanjima mogu biti korisni svima koji se bave proizvodnjom sojine pogače i sojinog ulja. Eksperimentalna istraživanja obavljana su na ekstruderu tip E-751 i presi tip PM-5S, ali su rezultati primenjivi i na drugim ekstruderima i presama drugih proizvođača koji koriste soju kao sirovinu i proizvode  sojinu pogaču i sojino ulje. Na osnovu izvršenih istraživanja, obrađenih i prodis___________________Doktorska disertacija,  autor:Kukić Predrag____________________________________________________________________________________IV od 34kutovanih rezultata došlo se do funkcionalnih zavisnosti između pojedinih parametara ekstruzije i od promenljivih karakteristika ulazne sirovine sa jedne strane i karakteristika ekstrudata i sojinog ulja sa druge strane i na osnovu toga došlo se do određenih zaključaka. Na osnovu eksperimentralnih ispitivanja ocenjen je uticaj promene odabranih fizičkohemijskih svojstava soje pri ekstrudiranju zrna soje. U disertaciji se krenulo od analize polazne sirovine tj. soje i njenog sadržaja proteina, ulja, slobodnih masnih kiselina i vlage, a zatim variranjem režima rada ekstrudera tj. doziranja ulaznog materijala praćeno preko opterćenja pogonskog elektromotora ekstrudera izraženog preko jačine struje [A], površine otvora mlaznice i vlažnosti soje, praćen je sadržaj slobodnih masnih kiselina, fosfora i vlage u sojinom ulju posle presovanja ekstrudata, kao i sadržaj proteina, vlage, ulja, aktivnost ureaze i PDI u sojinoj pogači. Na osnovu sprovedenih istraživanja došlo se do funkcionalnih zavisnosti između zadatih režima rada ekstrudera, ulazne sirovine i odabranih fizičko-hemijskih svojstava soje pri ekstrudiranju zrna soje. Tako da se sa porastom površine otvora mlaznice i doziranja mase povećava se produkcija sojine pogače. Produkcija sojine pogače se povećava i kada se vlažnost ulazne sirovine povećava. Sa povećanjem vlažnosti ulazne sirovine i interakcije doziranja mase i površine otvora mlaznice sadržaj vlage u sojinoj pogači se povećava. Na osnovu izvedenih istraživanja može se tđ. zaključiti da sa povećanjem površine otvora mlaznice ekstrudera raste sadržaj ulja u sojinoj pogači za svaku od tri vlažnosti soje kao ulazne sirovine, dok sa povećanjem doziranja ulazne sirovine smanjuje se sadržaj  ulja u sojinoj pogači za svaku od tri mlaznice. Povećanjem površine otvora mlaznice ekstrudera, dolazi do smanjenja sadržaja proteina u sojinoj pogači, dok je obrnuto kod povećanja doziranja ulazne sirovine, tj. sa povećanjem doziranja sirovine u ekstruder povećava se sadržaj proteina u sojinoj pogači. Pozitivan efekat aktivnosti ureaze (∆pH) u___________________Doktorska disertacija,  autor:Kukić Predrag____________________________________________________________________________________V od 34sojinoj pogači je za veće vrednosti kako površine otvora mlaznice, tako i interakcije promenljivih W (vlažnosti soje) i D (doziranje mase soje određeno preko opterećenja elektromotora). U sojinoj pogači PDI se povećava sa povećanjem vlažnosti ulazne sirovine, površine otvora mlaznice ekstrudera i doziranja zrna soje kao ulazne sirovine. Razmatrajući dobijene podatke za sojino ulje dobijeno ceđenjem produkta ekstruzije dobijenog ekstruzijom soje sa predviđenim vlažnostima ulazne sirovine došlo se do zaključka da se produkcija ulja smanjuje sa povećanjem površine otvora mlaznice ekstrudera, a da pri povećanju doziranja ulazne sirovine povećava se produkcija sojinog ulja. Sadržaj vlage u sojinom ulju smanjuje se sa povećanjem površine mlaznice ekstrudera, kao i sa povećanjem doziranja ulazne sirovine. Na osnovu ocenjenog modela najveće vrednosti sadržaja SMK se postižu pri najmanjim razmatranim vrednostima vlažnosti ulazne sirovine, pri čemu sadržaj SMK se povećava sa povećanjem doziranja mase.           Sadržaj fosfora u ulju se smanjuje sa povećanjem doziranja ulazne sirovine u ekstruder. Veća temperatura eksturzije [oC] postiže se pri manjim vrednostima vlage i površine otvora mlaznice. Sa povećanjem doziranja mase i pri fiksnim vrednostima vlage i površine otvora mlaznice očekivana vrednost temperature eksturzije opada. Sa povećanjem doziranja sirovine u ekstruder maksimalna očekivana vrednost potrošene energija po kilogramu produkcije (sojina pogača + sojino ulje) se smanjuje. Sa povećanjem doziranja sirovine u ekstruder maksimalna očekivana vrednost potrošene energije po kilogramu produkcije sojine pogače se smanjuje. Sa povećanjem doziranja sirovine u ekstruder minimalna očekivana vrednost potrošene energije po kilogramu produkcije sojinog ulja se povećava
AB The aim of this research is to determine the changes in chemical composition of the products at the outlet of the extruder and press (soya meal and oil), i.e. their quality in terms of their further use in animal feed production, food industry or the further use of soybean oil in bio-diesel production, with the functional correlation between the variable characteristics of feedstock and operating parameters of the extruder. Extrusion of soybeans was carried out on the extruder, type E-751, manufactured by "SREM PRODUKT" DOO from Lacarak, and pressing of oil on the press, type PM-5S, manufactured by "BRONTO" from Ukraine. Studies that were conducted in this PhD Thesis were done as a contribution to the expansion of knowledge related to the production process of soya cake and soya oil, and to provide practical guidelines for the optimal control and modeling of the extrusion process and squeezing soybeans, as well as for the designing of the extruder. Some experimental and laboratory tests were conducted in order to obtain and to analyze data that could determine changes in chemical composition of the products at the outlet of the extruder and press (soya cake and oil), i.e. their quality in terms of their further use in animal feed production, food industry or the further use of soybean oil in bio-diesel production, all with the functional correlation between variable characteristics of feedstock and operating parameters of the extruder. Experimental researches are intended for practical application, by which the production process of soya cake and soybean oil could be enhanced and optimized. The results obtained in these researches can be useful to everyone involved in the production of soya cake and soya oil. Experimental studies were carried out on the extruder, type E-751 and the press, type PM5S, but the results are also applicable to other extruders and presses from other manufacturers, that use soybean as a raw material and produce soybean cake and soybean oil. The conducted researches, processed and discussed results have led to the functional correlations between different extrusion parameters and variable characteristics of the incoming raw___________________Doktorska disertacija,  autor:Kukić Predrag____________________________________________________________________________________IX od 34materials on the one hand, and the characteristics of the extrudate and soybean oil on the other hand, and further on to the certain conclusions. Based on the experimental researches, the impact of changes in selected physical and chemical properties of soybeans was evaluated in the extrusion of soybeans. The PhD Thesis started with the analysis of raw material i.e. soybean and its composition: protein, oil, free fatty acids (FFA) and moisture, and then, the content of free fatty acids, phosphorus and moisture in soybean oil after pressing the extrudate were monitored, as well as protein, moisture, oil, urease activity and PDI (Protein Dispersibility Index) in soya cake by varying the operating mode of the extruder, i.e. feeding of raw material, monitored via load of the main drive motor of the extruder expressed through amperage [A], the die openings surface and moisture of soybeans. The conducted researches have led to the functional correlations between the preset operating modes of the extruder, incoming raw material and selected physical and chemical properties of soybeans in the extrusion process. Thus, with increasing the die openings surface and feeding mass, the production of soya cake is being increased as well. Production of soya cake is also increased with the increase of moisture in the incoming raw material. Moisture content in soya cake is being increased with the increase of moisture content in a feedstock and interactions of feeding mass and the die openings surface. Based on the conducted researches, it can be concluded that the oil content in soybean cake is being increased with the increase of the extruder die openings surface for each of the three moisture content in soybean as a feedstock, while the oil content in soybean cake is being decreased with increased dosage of feedstock for each of the three extruder dies. By increasing the surface area of the extruder die openings, there is a decrease of the protein content in soya expeller cake, while vice versa, with an increase in the dosing of input raw material, i.e. with increasing dosage of raw material to the extruder, the protein content in soya expeller cake is increased. The positive effect of urease activity (ΔpH) in soya cake is for larger values of the surface of extruder die___________________Doktorska disertacija,  autor:Kukić Predrag____________________________________________________________________________________X od 34openings as well as for the interaction of variables W (moisture in soybean) and D (soybean mass dosage determined via the load of the main electric motor). PDI in soybean cake increases with the increase in moisture content of raw material, the surface of the extruder die openings and the dosing of soybeans as a feedstock. Considering the data obtained for soybean oil, manufactured by squeezing the extruded soy product with the predicted moisture content in the feedstock, it has been concluded that the oil production decreases with increasing the surface of the extruder die openings, while by increasing the dosage of incoming raw material, the production of soybean oil is increased. Moisture content in soybean oil is reduced with the increase of the surface of the extruder die openings, as well as with an increase in dosage of feedstock. Based on the evaluated model, the largest values of FFA content were achieved with the smallest considered values for the moisture content in the incoming feedstock, wherein the content of FFA increases with increasing the feeding mass. The phosphorus content in the oil decreases with increasing the feeding of raw material into extruder. Higher extrusion temperatures [oC] are achieved at the lower values of moisture and surface of extruder die openings. With increasing the feeding mass and fixed values of moisture content and die openings surface, the expected value of the extrusion temperature decreases. With increasing the dosage of raw materials into the extruder, the largest expected value for the energy, spent per kilogram of production (soybean cake + soybean oil), decreases. By increasing the dosage of raw materials in the extruder, the largest expected value for the energy, spent per kilogram of soya cake production, is reduced. With increasing the dosage of raw materials in the extruder, the lowest expected value of energy, spent per kilogram of soybean oil production, increases
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8

Vesna, Vujasinović. "Uticaj termičke obrade na nutritivnu vrednost i oksidativnu stabilnost ulja semena uljane tikve golice Cucurbita pepoL". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2011. http://dx.doi.org/10.2298/NS20110927VUJASINOVIC.

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Abstract (sommario):
Jedno od specijalnih jestivih ulja koje se proizvodi isključivo mehaničkim postupkom i koje se može uvrstiti u grupu funkcionalnih prehrambenih proizvoda je ulje semena tikve. Ovo ulje je veoma atraktivno za potrošace, pre svega zbog svoje karakteristične arome, visoke nutritivne vrednosti i dokazanog blagotvornog delovanja na zdravlje. Cilj istraživanja u okviru ove teze je bio da se izvrši karakterizacija senzorsko nutritivnog kvaliteta i oksidativne stabilnosti hladno presovanih i devičanskih ulja tikve sa tržišta, ispita uticaj termičke obrade semena na kvalitet, nutritivnu vrednost i održivost devičanskog tikvinog ulja i da se definišu senzorska svojstva i održivost hladno presovanog ulja semena tikve. U cilju karakterizacije ulja ispitivanja su sprovedena na većem broju uzoraka hladno presovanih i devičanskih ulja semenatikve nabavljenih neposredno, slučajnim izborom sa domaćeg i inostranog tržišta. Definisana su osnovna svojstva i najbitnije kvalitativne razlike između ove dve kategorije ulja proizvedenih različitom tehnologijom. Iako se proizvode iz iste sirovine tikvina ulja se međusobno bitno razlikuju po brojnim kvalitativnim, a naročito senzorskim svojstvima (ukus, miris, aroma i boja) što može da stvori zabune kodpotrošaca. Ispitivanjima uticaja različite termičke obrade semena utvrđeno je da proces pečenja mlevenog materijala neposredno pre presovanja bitno utiče na kvalitativna svojstva i održivost devičanskog ulja. Termička obrada mlevenog semena pri temperaturi u interval od 90 do 130 oC i vremenu od 30 do 70 min pokazala je različit uticaj na senzorski kvalitet, sadržaj bioaktivnih komponenata i oksidativnu stabilnost ulja ispoljavajući kako negativan, tako i pozitivan efekat. U delu istraživanja vezanih za definisanje senzorskih svojstava i određivanje održivosti ulja izdvojenog postupkom hladnog presovanja osušenog semena tikve na pužnoj presi, ustanovljeno je da se najkvalitetnije ulje dobije pri prvom presovanju, buduci da je aroma ulja najbolja, pri tom su kiselinski i peroksidni broj najmanji, a indukcioni period najduži. Ovo se potvrdilo, kako pri presovanju samo semena golice, tako i pri presovanju golice sa dodatkom semena sa ljuskom. Promene najbitnijih pokazatelja u cilju odredivanja održivosti ulja praćene su periodično u trajanju od 2 godine. Utom periodu došlo je do izvesnog pogoršanja senzorskog kvaliteta ulja, određenog porasta kiselinskog i peroksidnog broja, kao i do smanjenja indukcionog perioda. Medutim, bez obzira na intenzitet nastalih promena, ulja su odgovarala svim zakonskim normama kvaliteta i nakon dve godine čuvanja. Ipak, radi obezbeđenja vrhunskog kvaliteta za rok trajanja hladno presovanih ulja semena tikve golice može se preporuciti period najviše do godinu dana.
Pumpkin seed oil is one of the specialty oils produced only by mechanical procedure and can be classified in the group of functional food products. This oil is very attractive (interesting) for the consumers first of all for its characteristic flavour, high nutritive value and proved beneficial effect on health. The aim of the investigations in the scope of this thesis was to characterize the sensoric-nutritive quality and oxidative stability of cold pressed and virgin pumpkin seed oils from the market, to investigate the effect (influence) of heat treatment of seed on quality, nutritive value and stability of virgin pumpkin seed oil and to define the sensory characteristics and stability of cold pressed pumpkin seed oil. Aiming to characterize the oil, a number of cold pressed and virgin pumpkin seed oil samples, randomly taken from the domestic and foreign market, were investigated (analyzed). The basic characteristics and most important qualitative differences between these two categories of oils produced applying different technologies were defined. Both types of pumpkin seed oils are produced from the same raw material, however, they differ significantly regarding a number of quality, and expecially sensory proterties (taste, odour, flavour and colour), so the consumers may become embarrassed. Investigating the influence of different heat treatment of seed, it was found that the roasting of ground material before the pressing affects significantly the quality characteristics and stability of virgin oil. The heat treatment of ground seed at temperatures 90 to 130 °C, for 30 to 70 min, showed different influence on sensory quality, content of bioactive components and oxidative stability of oil, exhibiting both negative and positive effect. In the part dealing with the defining of sensory characteristics and stability determination of oil obtained by cold pressure of dried pumpkin seed on screw press, it was found that most quality oil was obtained by the first pressing process, the oil flavur is the best, with lowest acid and peroxide value, and the induction period is the longest. This was confirmed by pressing both hull-less pumpkin and hull-less with the addition of pumpkin seed with hull. The most important characteristics for oil stability were followed for two years. In this period a certain deterioration of sensory quality was found, the acid and peroxide value increased, and the induction period decreased. However, disregarding the intensity of changes, the oil samples are in accordance with all legal quality normatives even after two years from the production date. However, in order to maintain the high (first-class) quality of cold pressed oil of hull-less pumpkin seed, the recomended period for the shelf-life of oil is one year.
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9

Svetlana, Milošević. "Ekstrakcija ginka (Ginkgo biloba L.) ugljenik (IV)-oksidom pod pritiskom". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2011. https://www.cris.uns.ac.rs/record.jsf?recordId=76803&source=NDLTD&language=en.

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Abstract (sommario):
U okviru ove disertacije izvršeno je preparatvno izolovanje etarskog ulja lišća ginka (Ginkgo biloba L.) destilacijom pomoću vodene pare, u cilju određivanja pojedinih fizičko-hemijskih parametara. Oficinalnim postupkom određen je sadržaj etarskog ulja u lišću ginka i iznosi 0,0083%. Lišće ginka je ekstrahovano klasičnim rastvaračima tj. smešom alkohol-voda, pri čemu je koncentracija alkohola iznosila 40% (m/m). Primenom navedenog rastvarača, izvršena je višestupna protivstrujna ekstrakcija (u pet stupnjeva) pri čemu je dobijen tečni ekstrakt (Extracta fluida) sa relativno visokim sadržajem ekstraktivnih materija (17,06%). Tečni ekstrakt je direktno korišćen za dobijanje suvog ekstrakta lišća ginka (Extracta sicca)primenomvsušnie sa raspršivanjem (spray dryer). Kvalitativna i kvantitativna karakterzacija izvršena je primenom postupka tečne hromatografije na tankom sloju (HPTLC) i određen sadržaj ukupnih flavonoida sračunatih na rutin, a i na katehin, a određen je i sadržaj ukupnih fenola sračunatih na hlorogensku kiselinu. Glavni deo doktorske disertacije predstavlja ekstrakcija sistema lišće ginka-ugljenik (IV)-oksid pod pritiskom, pri čemu je ispitivan uticaj stepena usitnjenosti droge na prinos ekstrakcije, i korišćen koeficijent brze i spore ekstrakcije kao mera kinetičkog ponašanja ekstrakcije. Dobijeni rezultati ispitivanja su pokazali značajan uticaj stepena usitnjenosti droge na brzinu ekstrakcije, pogotovo, kod ekstrakcije natkritičnim ugljenik (IV) oksidom. Radi izbora optimalnog protoka ekstragensa ispitivani su sledeći protoci 0,095, 0,194 i 0,277 kg/h . Na osnovu prinosa ekstrakcije usvojeno je da je protok ekstragensa od 0,194 kg/h optimalan. Prinos ekstrakcije je ispitivan korišćenjem dva postupka ekstrakcije, i to: ekstrakcija tečnim ugljenik (IV) -oksidom (temperatura ispod kritične temperature Tc= 31,1oC, a pritisak nešto ispod ili iznad kritičnog pritiska pc=73,8 bar), i ekstrakcija natkritičnim ugljenik (IV)- oksidom (pritisak i temperatura iznad kritičnih vrednosti pritiska i temperature). U natkritičnoj oblasti promenom pritiska se značajno menjaju svojstva ekstragensa, povećava se sposobnost rastvaranja, dielektrična konstanta i dr. Ispitivan je uticaj temperature na prinos ekstrakcije (izotermni proces), pri čemu se dobijaju rezultati koji se ne mogu objasniti jednostavno, analizirajući samo uticaj gustine rastvarača na moć rastvaranja, već se za objašnjenje dobijenih rezultata uključuje i uticaj napona pare ekstrahovane komponente, tako da rastvorljivost komponente može da se poveća, smanji ili ostane ista sa povećanjem temperature na konstantnom pritisku, u zavisnosti koji uticaj je dominantniji. Kod izotermnih postupaka prinos ekstrakcije raste sa povećanjem pritiska ekstrakcije, što je u saglasnosti sa teoretskim principima. S druge strane, ekstrakti dobijeni pri višim pritiscima imaju manji sadržaj etarskog ulja što se objašnjava činjenicom da veći pritisci imaju veću moć rastvaranja glavnih komponenata kao i komponenata kao što su smole, voskovi i masna ulja. Kvalitativnom i kvantitativnom analizom selektovanih ekstrakata dobijenih tečnim (130 bar, 20oC, 3 h) i natkritičnim (100 bar, 40o C, 4 h) ugljenik (IV)-oksidom, kao i etarska ulja izolovana iz ovih ekstrakata nađeno je da ispitivani uzorci sadrže nalkane, račvaste alkane i jedinjenja sa kiseonikom, među kojima posebno mesto zauzimaju fenoli sa zasićenim i nezasićenim alkil ostacima.Izvršena je uporedna anliza etarskog ulja dobijenog destilacijom lišća ginka pomoću vodene pare i etarskih ulja dobijenih iz selektovanih ekstrakata. Interesantan je podatak koji se odnosi na sadržaj etarskog ulja u drogi određen direktnom destilacijom droge pomoću vodene pare i izdvajanjem etarskih ulja iz ekstrakata takođe destilacijom pomoću vodene pare. U ovom drugom slučaju dobija se, preračunavanjem, sadržaj etarskog ulja u drogi višestruko veći (4-10 puta) od sadržaja, određenog oficinalnim postupkom, u drogi. Ova pojava se objašnjava uvođenjem pojma „vezano“ etarsko ulje i „slobodno“ etarsko ulje. Ekstrakcijom ugljenik (IV)-oksidom pod pritiskom tzv. vezano etarsko ulje se oslobađa voskova i masnog ulja što se odražava na njegovu povećanu količinu u CO2-ekstraktima. Na kraju u ovoj disertaciji izvršeno je modelovanje ekstrakcionog sistema lišće Ginkgo biloba – ugljenik (IV)-oksid pod pritiskom korišćenjem model jednačine Naika i saradnika, modifikovane model jednačine Reverchon i Sesti-Osseo kao i model, češće korišćen, koji je predložila Sovová. Korišćeni modeli mogu relativno uspešno da se koriste za opisivanje ekstrakcionog sistema lišće Ginkgo biloba – ugljenik (IV)-oksid pod pritiskom. Radi iznalaženja najpovoljnijih uslova ekstrakcije primenjen je metod odzivne površine variranjem parametra ekstrakcije (pritisak, temperatura i vreme ekstrakcije). Na osnovu eksperimentalnih rezultata dobijen je polinom drugog reda za izračunavanje optimalnog prinosa ekstrakcije i određeni su najpovoljniji uslovi ekstrakcije kao i međusobni uticaji pojedinih parametra.
Within this thesis preparative isolation of essential oil from leaves of ginkgo (Ginkgo biloba L.) by steam distillation was carried out, in order to determine some physico-chemical parameters. The essential oil content in the leaves of ginkgo wass determined by an officinal procedure and its value is 0.0083%. Ginkgo leaves were extracted with conventional solvents, i.e. alcohol-water mixture, where the alcohol concentration was 40% (w/w). The forementioned solvent was used to carry out a multistage counter-current extraction (five stages) by which the liquid extract (Extracta fluida) with a relatively high content of extracts (17.06%) was obtained. The liquid extract was directly used to obtain a dry extract of ginkgo leaves (Extracta sicca) by spay drying. The qualitative and quantitative characterisation was based on the proceedings of liquid thin layer chromatography (HPTLC), the content of total flavonoids expressed as rutin, and as catechin, and the total phenol content expressed as chlorogenic acid was determined. The main part of the doctoral thesis is the extraction system of ginkgo leaves-carbon (IV) oxide under pressure, in which the effect of the drug particle size on the extraction yield was studied, and as a measure of the kinetic behavior of extraction the coefficient of fast and slow extraction was used. The obtained results showed a significant effect of the drug particle size on the speed of extraction, particularly, the extraction with supercritical carbon (IV) oxide. For the purpose of selecting the optimal flow of the solvent several flowrates were investigated 0.095, 0.194 and 0.277 kg/h. Based on the yield of extraction the solvent flowrate of 0.194 kg/h was assumed as optimal. The extraction yield was investigated using two extraction procedures: extraction with liquid carbon (IV) oxide (temperature below the critical temperature Tc = 31.1 0C and pressure slightly below or above the critical pressure pc = 73.8 bar), and extraction with supercritical carbon (IV) oxide (pressure and temperature above the critical values of pressure and temperature). In the supercritical area the change in pressure significantly the influences the properties of the solvent, increases the ability of dissolving, dielectric constant, etc. The effect of temperature on extraction yield was examined (isothermal process), where the obtained results can not be explained simply by analyzing only the effect of solvent density on the power of dissolution, but to explain these results the effect of vapor pressure of the extracted components must be included, so that the solubility of the component may increase, decrease or remain the same with increasing temperature at constant pressure, depending on which influence is dominant. In isothermal processes the extraction yield increases with increasing pressure of extraction, which is consistent with theoretical principles. On the other hand, extracts obtained at high pressures have a lower content of essential oils which can be explained by the fact that higher pressures have a greater power of dissolution of the main components as well as components such as resins, waxes and fatty oils. The qualitative and quantitative analysis of the selected extracts obtained with liquid (130 bar, 20 0C, 3 h) and supercritical (100 bar, 40 0C, 4 h) carbon (IV) oxide, and essential oils isolated from these extracts showed that the studied samples contain n-alkanes, branched alkanes and compounds with oxygen, including phenols with saturated and unsaturated alkyl residues. A comparative analysis of the essential oil obtained by distillation of ginkgo leaves by steam and essential oil obtained from selected extracts was carried out. An interesting fact concerning the essential oil content in the drug determined by direct distillation of drugs by steam and separating the essential oils from extracts also produced by steam distillation. In the other case, by calculation, the obtained essential oil content in the drug is several times higher (4-10 times) of content, determined by an fficinal procedure, in the drug. This phenomenon is explained by introducing the notion of "linked" essential oil and "free" essential oil. The extraction with carbon (IV) oxide under pressure the so called linked essential oil is released from waxes and fatty oils which is reflected in its increased amount in CO2-extracts. At the end of this dissertation the modeling of the extraction system leaves of Ginkgo biloba - carbon (IV) oxide under pressure was carried out using the model equation of Naik and associates, the modified model equation of Reverchon and Sesti Osseo and also like a frequently used model proposed Sovová. The mentioned models can be relatively used to describe the extraction system leaves of Ginkgo biloba - carbon (IV) oxide under pressure. In order to find the most favorable conditions of extraction, the response surface methodology varying extraction parameters was used (pressure, temperature and extraction time). Based on the experimental results a second order polynom for the calculation of the optimum yield of extraction was obtained and the extraction conditions and the mutual influence of some parameters were determined.
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10

Ranko, Romanić. "HEMOMETRIJSKI PRISTUP OPTIMIZACIJI TEHNOLOŠKIH PARAMETARA PROIZVODNJE HLADNO PRESOVANOG ULJA SEMENA VISOKOOLEINSKOG SUNCOKRETA". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2015. http://www.cris.uns.ac.rs/record.jsf?recordId=95781&source=NDLTD&language=en.

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Abstract (sommario):
U okviru ove doktorske disertacije ispitani su i utvrđeni optimalni uslovi za proces ljuštenja semena suncokreta visokooleinskog tipa, kao sirovine za proizvodnju ulja. Sprovedena istraživanja su dala podatke o optimalnim vrednostima sadržaja vlage u semenu i pritiska vazduha u ljuštilici na osnovu kojih je utvrđen model za ljuštenje semena. Sprovedenim istraživanjima obuhvaćeno je i ispitivanje uticaja promenljivih tehnoloških parametara, sadržaja ljuske u opsegu od 0 do 20% i sadržaja nečistoća u opsegu od 0 do 10% na sastav i kvalitet hladno presovanih ulja i pogače, prinos ulja, oksidativnu stabilnost, senzorski kvalitet i boju hladno presovanih ulja semena suncokreta visokooleinskog tipa.Dobijeni rezultati su obrađeni primenom savremenih klasifikacionih (klaster analiza i analiza glavnih kompomenata) i regresionih hemometrijskih metoda i postavljeni hemometrijski modeli čija bi primena doprinela proizvodnji hladno presovanog ulja vrhunskog kvaliteta i visoke oksidativne stabilnosti. Utvrđeno je da su definisani modeli statistički validni i da se mogu primeniti za optimizaciju tehnoloških parametara u proizvodnji hladno presovanog ulja semena suncokreta visokooleinskog tipa. Validnost postavljenih modela, odnosno kvalitet dobijenih korelacija su procenjeni na osnovu parametara unakrsne validacije.Maksimalna efektivnost ljuštenja semena suncokreta visokooleinskog tipa može se postići pri optimalnim uslovima tj. sadržaju vlage u semenu 6,0% i pritisku vazduha u ljuštilici 800 kPa. Hladno presovano ulje semena suncokreta visokooleinskog tipa se, u pogledu sastava i kvaliteta ulja i pogače, prinosa ulja, oksidativne stabilnosti, senzorskog kvaliteta i boje ulja, može proizvoditi od semena koje sadrži 10-20% ljuske i 0-5% nečistoća.
In this dissertation the optimal conditions for the dehulling process of high-oleic sunflower seeds, as raw material for oil production, were tested and determined. The conducted studies provided data for the optimal values of moisture content in the seed and the air pressure in the seed dehulling machine, what presented the base for determination of the dehulling model. Also, conducted studies examine the effect of variable technological parameters, such as content of hull (ranging from 0 to 20%) and the impurities content (ranging from 0 to 10%) on the composition and quality of oil and cake, oil yield, oxidative stability, sensory quality and colour of cold pressed high-oleic sunflower oil.The obtained results were analyzed by modern classification (cluster analysis and principal component analysis) and regression chemometrics methods, and chemometric models whose implementation could contribute to the production of cold pressed oil of high quality and high oxidative stability were set. It was found that the defined mathematical models are statistically valid and that they could be used to optimize the technological parameters of production of cold pressed high-oleic sunflower oil. The validity of the set models, that is the quality of obtained correlations, were estimated based on the parameters of cross-validation.The maximum effectiveness of high-oleic sunflower seeds dehulling can be achieved under optimal conditions, i.e. when the moisture content in seed is 6,0% and when the air pressure in seed dehulling machine is 800 kPa. Regarding composition and quality of the oil and cake, oil yield, oxidative stability, sensory quality and color, cold pressed high-oleic sunflower oil could be produced from seed containing 10-20% hull and 0-5% impurities.
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11

Branimir, Pavlić. "Valorizacija sporednog proizvoda žalfije (Salvia officinalis L.) u cilju dobijanja bioaktivnih jedinjenja savremenim tehnikama ekstrakcije". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2017. http://www.cris.uns.ac.rs/record.jsf?recordId=104416&source=NDLTD&language=en.

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Abstract (sommario):
Glavni cilj istraživanja ove doktorske disertacije je bio valorizacija sporednog proizvoda žalfije (Salvia officinalis L.) iz fabrike čaja za dobijanje visoko-vrednih ekstrakata željenih osobina koji bi imali primenu u gotovim proizvodima prehrambene, kozmetičke i farmaceutske industrije.U cilju ekstrakcije polifenolnih jedinjenja su primenjene konvencionalne (maceracija) i savremene (ultrazvučna ekstrakcija, mikrotalasna ekstrakcija i ekstrakcija subkritičnom vodom) ekstrakcione tehnike. U postupaku maceracije je optimizovana koncentracija etanola u ekstragensu, dok je za optimizaciju savremenih ekstrakcionih tehnika primenjen eksperimentalni dizajn i metoda odzivne površine. Prinos polifenola (ukupnih fenola i ukupnih flavonoida) i antioksidativna aktivnost određena različitim in vitro testovima su bili ispitivani odzivi. Za svaki od navedenih ekstrakcionih postupaka je ispitivan uticaj glavnih ekstrakcionih parametara: ultrazvučna ekstrakcija (temperatura, vreme ekstrakcije i snaga ultrazvuka), mikrotalasna ekstrakcija (koncentracija etanola, vreme ekstrakcije i odnos rastvarač-droga) i ekstrakcija subkritičnom vodom (temperatura, vreme ekstrakcije i koncentracija HCl u ekstragensu). Tečni ekstrakti dobijeni ultrazvučnom, mikrotalasnom i subkritičnom ekstrakcijom su pokazali izuzetno visoku antioksidativnu aktivnost određenu „hvatanjem“ DPPH i O2∙- radikala i kapacitetom redukcije Fe3+ jona i imali su znatno veći sadržaj polifenola u odnosu na ekstrakte dobijene maceracijom.U cilju ekstrakcije terpenoidnih jedinjenja su primenjeni postupci Soxhlet ekstrakcije, destilacije vodenom parom i ekstrakcije superkritičnim CO2. Postupak superkritične ekstrakcije je optimizovan metodom odzivne površine i optimalni uslovi ekstrakcije su bili pritisak 290 bar, temperatura 55˚C i protok CO2 od 0,4 kg/h, dok su predviđene i eksperimentalne vrednosti prinosa ekstrakcije bile 8,90 i 8,84%. Hemijskom analizom lipofilnih ekstrakata i etarskog ulja je utvrđeno da su oksidovani monoterpeni (α-tujon i kamfor), oksidovani seskviterpeni (viridiflorol) i polifenolni diterpeni (epirosmanol) dominantna jedinjenja prisutna u ovim uzorcima.Tečni ekstrakti žalfije dobijeni konvencionalnim i savremenim ekstrakcionim tehnikama su spray drying tehnikom osušeni u cilju prevođenja u stabilniju formu suvog ekstrakta. Suvim ekstraktima su određene fizičko-hemijske osobine (hemijski sastav, sadržaj vlage, higroskopnost, moć rehidratacije, WAI i WSI) i biološka aktivnost (antimikrobna i antioksidativna aktivnost) i procenjena je njihova mogućnost primene u prehrambenoj i farmaceutskoj industriji.
The main aim of this dissertation was valorization of sage (Salvia officinalis L.) by-product from filter-tea factory for recovery of high-value extracts with desirable properties for application in food, cosmetics and pharmaceutical products.Conventional (maceration) and novel (ultrasound-assisted, microwave-assisted and subcritical water extraction) extraction techniques were applied for polyphenols recovery. Ethanol concentration was optimized in maceration process, while experimental design and response surface methodology were applied for optimization of novel extraction techniques. Polyphenols yield (total phenols and total flavonoids) and antioxidant activity, determined by various in vitro assays, were investigated responses. Influence of main process parameters was determined for each technique: ultrasound-assisted extraction (temperature, extraction time and ultrasonic power), microwave-assisted extraction (ethanol concentration, extraction time and sample-solvent ratio) and subcritical water extraction (temperature, extraction time and HCl concentration in solvent). Liquid extracts obtained by novel extraction technique exhibited higher antioxidant activity determined by scavenging of DPPH and O2∙- radicals and reduction of Fe3+ and also provided higher polyphenols yield comparing to extracts obtained by maceration. Soxhlet extraction, hydrodistillation and supercritical fluid extraction were applied for terpenoids recovery. Supercritical fluid extraction process was optimized by response surface methodology and optimal conditions were pressure of 290 bar, temperature of 55˚C and CO2 flow rate of 0.4 kg/h, while predicted and experimentally obtained values of total extraction yield at these conditions were 8.90 i 8.84%, respectively. According to chemical analysis, the most abundant compounds in lipid extracts and essential oil were oxygenated monoterpenes (α-thujone and camphor), oxygenated sesquiterpenes (viridiflorol) and diterpene polyphenols (epirosmanol).Sage liquid extracts obtained by conventional and novel extraction techniques were spray dried in order to obtain dry extract form. Physico-chemical properties (chemical profile, moisture content, hygroscopicity, rehydratation time, WAI and WSI) and biological activity (antimicrobial and antioxidant activity) were determined in dry extracts and their potential application in food and pharmaceutical formulations was discussed.
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12

Mohamed, Elgndi Ahmed. "Farmakološko delovanje ekstrakata odabranih aromatičnih/lekovitih biljaka". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2018. https://www.cris.uns.ac.rs/record.jsf?recordId=106922&source=NDLTD&language=en.

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Abstract (sommario):
Glavni cilj ove disertacije koji obuhvata dobijanje i hemijsku karakterizaciju ekstrakata i etarskih ulja rtanjskog čaja (Satureja montana L.), bosiljka (Ocimum basilicum L.) i korijandera (Coriandrum sativum L.), kao i njihove smeše, je određivanje biološke aktivnosti dobijenih ekstrakata u in vitro uslovima pradenjem sposobnosti neutralizacije slobodnih radikala i antiproliferativne aktivnosti.Prvo je izvršena karakterizacija biljnih sirovina (rtanjski čaj, bosiljak i korijander), kao i njihove smeše jednakih masenih udela (CBS) u pogledu sadržaja vlage, srednjeg prečnika čestica i sadržaja etarskog ulja. U cilju dobijanja etarskih ulja i ekstrakata iz ispitivanih sirovina su primenjeni hidrodestilacija (konvencionalni postupak) i superkritična ekstrakcija (savremena tehnika). GC-MS analizom je određen kvalitativni sastav i relativni udeo pojedinačnih monoterpenskih ugljovodonika, oksidovanih monoterpena, seskviterpena i ostalih jedinjenja. Dalje je GC-FID analizom kvantitativno određen sadržaj i prinos pojedinačnih terpena (α-pinen, β-pinen, d-limonen, γ-terpinen, eukaliptol, linalool, kamfor, α-terpineol, geraniol, metil-havikol, karvakrol i eugenol) i izvršeno je poređenje uzoraka dobijenih tradicionalnim i savremenim postupcima.Etarskim uljima i lipofilnim ekstraktima je određena biološka aktivnost ispitivanjem antioksidativne i antiproliferativne aktivnosti. In vitro anti-oksidativna aktivnost superkritičnih ekstrakata i etarskih ulja je određena DPPH testom, dok je antiproliferativna aktivnost određena u in vitro uslovima na tri linije tumorskih delija (HeLa, MDA-MB-453, K562) i na normalne humane fibroblaste (MRC-5).U cilju boljeg određivanja sličnosti između etarskih ulja i lipofilnih ekstrakata rtanjskog čaja, bosiljka, korijandera i njihove smeše (CBS) su primenjene hemometrijska tehnike: analiza glavnih komponenata (Principal component analysis) i hijerarhijska klaster analiza (Hierarchical cluster analysis).
The main aim of this dissertation was recovery and chemical characterization of extracts and essential oils of winter savory (Satureja montana L.), basil (Ocimum basilicum L.) and coriander (Coriandrum sativum L.), as well as their mixture, and determination biological activity of extracts in in vitro conditions by capacity towards neutralization of free radicals and antiproliferative activity.Plant materials (winter savory, basil and coriander) and their mixture (CBS) were characterized in terms of moisture content, mean particle size and essential oil content. In order to obtain essential oil and extracts from investigated plants, hydrodistillation (conventional procedure) and supercritical fluid extraction (novel technique) were applied. GC-MS analysis was used for determination of qualitative content and relative abundance of monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpenes and other volatile compounds. Furthermore, GC-FID analysis was used for quantitative determination of content and yield of terpene compounds (α-pinene, β-pinene, d-limonene, γ-terpinene, eucalyptol, linalool, camphor, α-terpineol, geraniol, methyl-chavicol, carvacrol i eugenol) and samples obtained by traditional and novel techniques were compared. Biological potential of essential oil and lipophilic extracts was determined by antioxidant and antiproliferative activity. In vitro antioxidant activity of supercritical extracts and essential oils was determined by DPPH assay, while antiproliferative activity was determined in in vitro conditions on three cancer cell lines (HeLa, MDA-MB-453, K562) and on normal human fibroblasts (MRC-5).Chemometric techniques such as principal component analysis (PCA) i hierarchical cluster analysis (HCA) were applied for better understanding of similarities between essential oils and lipid extracts.
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13

Jelena, Bajac. "Dobijanje emulzionih nosača aktivnih materija primenom homogenizera i membranskim emulgovanjem u ćeliji sa mešanjem". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2018. https://www.cris.uns.ac.rs/record.jsf?recordId=107583&source=NDLTD&language=en.

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Abstract (sommario):
Cilj ove doktorske disertacije je dobijanje višestrukih V1/U/V2 emulzija kao nosača aktivnih materija u dvostepenom postupku, pri čemu se za drugi korak pripreme koristi tehnika membranskog emulgovanja (ME), na membrani od sinterovanog stakla implementiranoj u ćeliju sa mešanjem. Proces ME koristi se u svrhu unapređenja karakteristika formiranih emulzija, u smislu bolje kontrole veličine i raspodele veličina formiranih kapi, koje mogu da dovedu do razlika u stepenu inkapsulacije aktivnih materija u unutrašnjoj vodenoj fazi, u odnosu na proces u kome se za drugi korak pripreme emulzija koristi tehnika homogenizacije.Kompletna optimizacija sastava V1/U emulzija, koja obuhvata određivanje koncentracije hidrofobnog emulgatora (PGPR), lipofobne materije (NaCl) i tikvinog ulja kao sekundarne aktivne komponente, rezultirala je formiranjem stabilnih nanoemulzija sa poboljšanim nutritivnim svojstvima. Nutritivno unapređeni emulzioni sistemi optimizovanog sastava korišćeni su za inkapsulaciju primarnih aktivnih komponenata (vodenog i etanolnog ekstrakata belog luka) u cilju zaštite bioaktivnih sastojaka i maskiranja neprijatnog mirisa i ukusa. Nakon definisanja sastava svih faza višestrukih emulzija, koje ukljuĉuje određivanje tipa hidrofilnog emulgatora i njegove koncentracije, kao i ispitivanja uticaja dodavanja osmotskog regulatora (glukoze) u spoljašnju vodenu fazu na stabilnost sistema i difuziju lipofoba, formirane su višestruke emulzije sa unetim aktivnim komponentama membranskim emulgovanjem u ćeliji sa mešanjem. Sistematiĉna karakterizacija membrane od sinter stakla kao ekonomski opravdanog membranskog materijala, dala je mogućnost njegove primene u procesu. Detaljno ispitivanje uticaja procesnih parametara (transmembranskog pritiska i brzine mešanja) i višekriterijumska optimizacija procesa ME, dovela su do formiranja višestrukih emulzija sa užom raspodelom veličina kapi, koja je indirektno uticala i na poboljšanje zadržavanja inkapsuliranog materijala u unutrašnjosti emulzija tokom vremena, u odnosu na emulzije pripremljene u postupku homogenizacije.
The aim of this doctoral thesis was to prepare multiple W/O/W emulsions with encapsulated active substances in both phases, by a two-step process, where the stirred cell membrane emulsification (ME) process, with a sintered glass filter disk as a membrane, was used as the second step, instead of conventional process (homogenization). The ME process was employed in order to improve the characteristics of the formed emulsions, in terms of better control of the size and droplet size distribution, that can change the encapsulation degree of active ingredients in the internal aqueous phase.The complete optimization of W/O emulsion composition, which includes determination of optimal contents of a hydrophobic emulsifier (PGPR), a lipophobic substance (NaCl) and pumpkin seed oil as an active component of the oil phase, resulted in the formation of stable nanoemulsions with improved nutritional properties. This nutritionally enhanced emulsion was used to encapsulate primary active ingredients (aqueous and ethanol garlic extract), in order to protect instable bioactive compounds of the extracts and mask the unpleasant smell and taste. After defining the composition of all phases of multiple emulsions, which includes determination of a suitable hydrophilic emulsifier and its optimal content, as well as examining the effect of addition of an osmotic regulator (glucose) in the external aqueous phase on the emulsion stability and lipophobe diffusion, multiple emulsions with encapsulated active components were formed by membrane emulsification in the stirred cell. The complete characterization of the sintered glass as an economically favourable membrane material, gave the possibility of its application in the process. Investigation of the influence of process parameters (transmembrane pressure and impeller rotation speed) and multiobjective optimization of ME, led to the formation of the multiple emulsions with a narrow droplet size distribution, which had improved retention of encapsulated material in the internal water phase over time, relative to the emulsions prepared by the homogenization process.
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14

Marina, Kalić. "Fizičko-hemijska i reološka karakterizacija mikrokapsula ribljeg ulja inkorporiranih u čokoladni matriks". Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2020. https://www.cris.uns.ac.rs/record.jsf?recordId=114094&source=NDLTD&language=en.

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Abstract (sommario):
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.
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.
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15

Boris, Župan. "UTICAJ DODATKA LANENOG ULJA U HRANI NA PROMENU SADRŽAJA MASNIH KISELINA U MIŠIĆNOM TKIVU ŠARANA". Phd thesis, Univerzitet u Novom Sadu, Poljoprivredni fakultet u Novom Sadu, 2016. https://www.cris.uns.ac.rs/record.jsf?recordId=97698&source=NDLTD&language=en.

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Abstract (sommario):
Cilj istraživanja bio je da se utvrdi u kojoj meri dodavanje lanenog ulja u peletirane krmnesmješe i ishrana tovnog šarana tako obogaćenom hranom utječe na količinu masti ikompoziciju masnih kiselina u mesu ribe. Krmne smješe u svim grupama istraživanja su bileistog sirovinskog sastava, osim dodatka lanenog ulja koje se menjalo (2,0; 3,0; 4,0; 5,0% i 6%u drugom ogledu) i masti (Magnapac) koja je smanjivana za istu postotnu vrednost dodatkomlanenog ulja. Većim delom istraživanog razdoblja fizičko-hemijski parametri vode su u svimekspermentalnim ribnjacima varirali u pogodnim vrednostima za uzgoj toplovodnih riba. UdioC18:1 cis-9 statistički je značajno najniži u kontrolnoj grupi i iznosi 35,43%. Povećanjemvrednosti lanenog ulja povećava se i udio C18:1 cis-9. Statistički najviša vrednost C20:0 je koduzoraka hranjenih s dodatkom 5% lanenog ulja. Najniža vrednost C20:3 ω-3 je u kontrolnojgrupi i iznosi 0,22% a značajno najviša u grupi koja se hrani s dodatkom 5% lanenog ulja. Sobzirom na dodatak lanenog ulja u hrani, nema značajnih razlika kod ukupnih zasićenih,mononezasićenih, polinezasićenih i omega-6 masnih kiselina. Najveći udio ω-3 masnihkiselina utvrđen je u uzorcima šarana kojima je u hranu dodano 5% lanenog ulja (5,41%) Udrugom ogledu utvrđena je opravdanost upotrebe lanenog ulja u hrani za ribe u odnosu naefekte koji su dobijeni u mesu. Omjer ω-3/ω-6 masnih kiselina značajno se povećao u grupamakojima je u hranu dodat veći dio lanenog ulja (0,21 u kontrolnoj grupi do 0,30% u grupi sdodatkom 5% lanenog ulja). Vrednostiholesterola se nisu značajno menjale dodavanjemlanenog ulja u ishrani šarana.
The aim of this study was to determine to what extent adding flaxseed oil to pellet diet andfattening carp so enriched food affects the amount of fat and the composition of fatty acids infish meat. Feed mixtures in all the studied groups were the same composition, except for theaddition of linseed oil to be changed (2.0; 3.0; 4.0; 5.0% and 6%) and fat (Magnapac), whichwas reduced by the same percentage value addition linseed oil. During substantial period ofresearch physico-chemical parameters of water in all experimental ponds ranged in valuessuitable for the cultivation of warm-water fish. Share C18:1 cis-9 was statistically significantlylowest in the control group and amounted 35.43%. By increasing the value of flaxseed oilincreases the proportion of C18:1 cis-9. Statistical highest value of C20:0 in the samples fedwith the addition of 5% linseed oil. The lowest value of C20:3 ω-3 in the control group is0.22% and significantly highest in the group that feeds supplemented with 5% linseed oil. Dueto the addition of linseed oil in the food, there is no significant difference in total saturated,monounsaturated, polyunsaturated omega-6 fatty acids. The largest proportion of ω-3 fattyacids found in samples of carp which was in food supplemented with 5% linseed oil (5.41%).The experimental results of the second experiment show the usefulleness of using of linseed oilin fish food regearging the meat quality. The ratio ω-3/ω-6 fatty acid increased significantly inthe group that is added to food in a higher proportion of linseed oil (0.21 in the control groupto 0.30% in the group with addition of 5% linseed oil). The value of cholesterol was notsignificantly changed by adding linseed oil to the diet of carp.Accepted on Senate on:AS
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16

Snežana, Filip. "Ekstrakcija bosiljka (Ocimum basilicum, Lamiaceae) ugljendioksidom u superkritičnom stanju i modelovanje ekstrakcionog sistema". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2014. http://dx.doi.org/10.2298/NS20140117FILIP.

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Abstract (sommario):
U okviru ove doktorske disertacije, proučavana je ekstrakcija bosiljka (Ocimum basilicum L.) primenom postupka hidrodestilacije, Soxhlet ekstrakcije i ugljendioksidom u superkritičnom stanju. Određen je sadržaj etarskog ulja u drogi (0,565%), a primenom GC/MS(FID) metoda određen kvalitativni i kvantitativni sastav detektovanih komponenata. Identifikovane komponente svrstane su u nekoliko grupa (monoterpeni, seskviterpeni i njihovi oksidovani derivati). Rezultati ispitivanja pokazuju da je dominantno jedinjenje etarskog ulja bosiljka linalool (50,09%), i da ono pripada linaloolskom hemotipu (hemotip A).Ispitan je uticaj temperature (40-60°C) i pritiska (100–300 bar) superkritičnog ugljendioksida na promenu prinosa ekstrakta. Utvrđeno je da se kumulativni prinos ekstrakta povećava sa porastom pritiska ekstrakcije, dok u zavisnosti od temperature, prinos ekstrakcije zavisi od gustine rastvarača i napona pare komponenata u ekstraktu.Primenom sukcesivne (frakcione) superkritične ekstrakcije izvršeno je frakcionisanje, a dobijeni ekstrakti upoređivani u pogledu prinosa, kvalitativnog i kvantitativnog sastava.Ispitivanja hemijskog sastava CO2 ekstrakta (GC/MS i GC/FID) pokazala su da ekstrakti pored komponenata etarskog ulja sadrže i druga lipofilna jedinjenja (voskove, masna ulja, masne kiseline, fitosterole i sl.). Dominantne komponente u svim ispitivanim ekstraktima su linalool, eugenol i δ-kadinen, dok su α-bergamoten, germakren D, γ-kadinen, β-selinen i spatulenol komponente sa manjim saržajem.Na osnovu eksperimentalnih rezultata kinetike superkritične ekstrakcije izvršeno je modelovanje ekstrakcionog sistema bosiljak – superkritični CO2, primenom tri modela (Kandiah i Spiro, Brunner i Esquivel i sar.). Na osnovu srednjih vrednosti relativnog odstupanja modelovanih i eksperimentalnih vrednosti prinosa ekstrakcije, utvrđeno je da model Kandiah i Spiro pokazuje prihvatljivo slaganje, dok ostali modeli pokazuju lošije slaganje eksperimentalno određenih i modelom izračunatih prinosa ekstrakta.U završnoj fazi rada ispitan je antioksidativni potencijal etarskog ulja i CO2 ekstrakata, primenom DPPH metode. Najveću antioksidativnu aktivnost pokazao je ekstrakt dobijen na 100 bar, 60°C (IC50 = 18,93 μg/ml), koja je 5 puta veća od antioksidativne aktivnosti etarskog ulja bosiljka.
In this study, the extraction of basil (O. basilicum L.) ussing the hydrodistillation process, Soxhlet extraction and supercritical extraction with carbon dioxide were investigated. The content of essential oil was determined (0,565%), and the qualitative and quantitative composition of detected coumpound was made by GC/MS(FID). The identified coumpounds were classified into five groups (monoterpenes, sesquiterpenes and their oxidative derivates). The results of investigation shows that the dominant compound of basil essential oil is linalool (50,09%), and that it belongs to linalool chemotype (chemotype A).The influence of temperature (40-60°C) and pressure (100–300 bar) of supercritical carbon dioxide on extraction yields were studied. It was determined that the total yield of extract increases with the increaseing of extraction pressure, while the influence of temperature on the yield depends on the density of the solvent and vapor pressure of components in the extract.Fractional supercritical fluid extraction was performed, and obtained extracts were compared regarding of yield, and the qualitative and quantitative composition of the extract. Chemical analyses of CO2 extract by GC/MS and GC/FID showed that extract contains, besides essential oil componentes, other lipophilic compounds (waxes, fatty oils, fatty acids, phytosterols, etc.). The few compounds were dominant in all analyzed basil extracts: linalool, and to a lesser extent eugenol, δ-cadinene, α-bergamotene, germacrene D, γ-cadinene, β-selinene and spathulenol. Based on the experimental results of the extraction kinetics, a modeling of basil – supercritical CO2 extraction system was performed, using three models (Kandiah and Spiro, Brunner, and Esquivel et al.). Based on the average values of the relative deviations of modeled and experimental values of extraction yield, it was found that the model Kandiah and Spiro shows acceptable agreement, while other models show lower agreement of the experimentally determined and model calculated extraction yield.In finale phase of work the antioxidant potential of essential oil and CO2 extracts were examined, using DPPH method. The highest antioxidant activity showed CO2 extract obtained at 100 bar, 60°C (IC50 = 18,93 μg/ml), which is 5 time higher then antioxidant activity of basil essential oil.
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17

Biljana, Rabrenović. "Uticaj fizičko-hemijskih karakteristika semena uljane tikve (Cucurbita pepo L.) na kvalitet i nutritivna svojstva hladno presovanog ulja". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2012. https://www.cris.uns.ac.rs/record.jsf?recordId=76895&source=NDLTD&language=en.

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Abstract (sommario):
Hladno presovano ulje semena uljane tikve je proizvod specifičan za Srbiju, za razliku od zemalja u regionu koje imaju dugu tradiciju proizvodnje devičanskog tikvinog ulja. Tokom postupka hladnog presovanja sirovogosušenog semena uljane tikve na pužnoj presi temperatura izdvojenog ulja ne prelazi 50 oC, što se odražava na fizičko-hemijske, nutritivne i senzorne karakteristike kao i na oksidativnu stabilnost i antioksidativni potencijal ovog ulja. U cilju što bolje karakterizacije ovog proizvoda na našem tržištu, ispitan je kvalitet hladno presovanog tikvinog ulja poreklom iz semena više različitih slobodnooplodnih sorti i F1 hibrida, golosemenih i uljanih tikvi sa ljuskom, koje uspevaju u našoj zemlji. Hladno presovano ulje semena tikve odlikuju specifične senzorne karakteristike: pored izuzetno blage arome, mirisa na sirovo seme tikve i ukusa koji podseća na meso tikve, ovo ulje se posebno izdvaja po boji koja je kod ispitivanog ulja bila svetlo-smedja do crvenkasta. Prema senzornim karakteristikama (naročito boji) izdvojili su se uzorci ulja poreklom iz semena austrijskih hibrida. Na osnovu sastava masnih kiselina ovo ulje pripada olinsko-linolnom tipu, što ga svrstava u nutritivno veoma vredna biljna ulja, čemu doprinosi i visok sadržaj gama-tokoferola, koji je dominantan u tikvinom ulju. Određivanje sastava i sadržaja sterola je posebno bilo značajno kada je u pitanju hladno presovano tikvino ulje s obzirom da nema literaturnih podataka na tu temu. U ispitivanim uzorcima su bili dominantni delta-7 steroli, a određen je i izuzetno visok sadržaj skvalena, koji ima veoma važnu biološku funkciju. Ispitivano ulje je posedovalo dobar antiradikalski potencijal, koji je bio u snažnoj linearnoj zavisnosti sa sadržajem fenolnih materija. Ulje dobijeno ekstrakcijom iz pogače, koja je zaostala nakon hladnog presovanja semena, posedovalo je veći antiradikalski potencijal u odnosu na hladno presovano što je rezultat sadržaja fenolnih materija u većem procentu i nešto nižeg sadržaja tokoferola u odnosu na hladnopresovano ulje.
Cold-pressed pumpkin oil is a product specific to Serbia, given that other countries in the region traditionally produce virgin pumpkin oil. In the process of cold pressing raw-dried pumpkin seeds by screw press, the temperature of extracted oil does not exceed 50oC, which affects physical, chemical, nutritional and sensory characteristics of this oil, as well as its oxidative stability and antiradical capacity. For the purpose of more precise characterization of this product in the domestic market, the quality of cold pressed oil from seeds of many free breeding varieties and F1 hybrids – of both naked and husk seed pumpkins being grown in our country – was examined. Specific sensorial properties: light brown to reddish color, mild aroma, a smell similar to that of raw pumpkin seeds and a taste resembling that of pumpkin pulp are characteristic for this oil. As for sensory characteristics, the samples of oil from Austrian hybrid seeds, stood out. On the basis of fatty acid content, this oil belongs to the oleic-linoleic type, meaning it is a highly nutritional vegetable oil, which is also due to high levels of dominant gamma-tocopherol. Determination of the types and content of sterols was particularly important, given that there are no data specific to cold-pressed pumpkin oil in the literature. Delta-7 sterols are the most dominant sterols in examined oil samples and also very high content of squalene was found, which a compound with an important biological function is. The oil has an excellent antiradical capacity, showing a strong linear correlation with the amounts of phenolic compounds. Oil extracted from the cake, left over after the cold pressing of pumpkin seeds, had greater antiradical capacity than the samples of cold pressed oil, due to higher percentage of phenolic compounds and a slightly lower content of tocopherols compared to cold pressed oil.
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18

Seddiq, Mrihil Ali Esalami. "Karakterizacija kvaliteta, nutritivne vrednosti i stabilnosti devičanskih maslinovih ulja proizvedenih u različitim regionima Libije". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2018. https://www.cris.uns.ac.rs/record.jsf?recordId=107467&source=NDLTD&language=en.

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Abstract (sommario):
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).
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).
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19

Milena, Vujanović. "Hemijski sastav, biološke i funkcionalne karakteristike novih proizvoda od zove". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2020. https://www.cris.uns.ac.rs/record.jsf?recordId=115048&source=NDLTD&language=en.

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Abstract (sommario):
Glavni cilj ove doktorske disertacije je određivanje hemijskog sastava, bioloških i funkcionalnih karakteristika novih proizvoda od zove. Dobijanje proizvoda na bazi zove zasniva se na primeni tradicionalnih i savremenih tehnoloških procesa proizvodnje. Iskorišćenje prirodnog potencijala zove započeto je primenom tradicionalne i savremene (liofilizacija) tehnike sušenja. U cilju dobijanja visoko-vrednih ekstrakata ploda i cveta zove primenjene su tradicionalna (maceracija) i savremene (ultrazvučna i mikrotalasna) ekstrakcione tehnike sa dva ekstragensa (50% etanol i voda). Dobijanje matičnog soka od plodova zove podrazumevalo je primenu tradicionalnog načina ceđenja, dok je vino od plodova zove dobijeno po standardnom postupku proizvodnje vina. Vino je izloženo različitim temperaturnim tretmanima u različitom vremenskom periodu (60 °C u toku 5 minuta, 60 °C u toku 10 minuta, 70 °C u toku 5 minuta i bez toplotnog tretmana) u cilju evaluacije biološke aktivnosti dobijenog proizvoda. Etarsko ulje ploda i cveta zove je dobijeno hidrodestilacijom. Ispitivanje efikasnosti primenjenih tehnoloških postupaka sušenja i ekstrakcije je zasnovano na određivanju bioloških i funkcionalnih karakteristika dobijenih ekstrakata ploda i cveta zove. U ispitivanim ekstraktima ploda i cveta zove dominantne fenolne kiseline su hlorogenska i protokatehinska kiselina, a rutin i kvercetin-3-O-heksozid su dominantna flavonoidna jedinjenja. Biološke i funkcionalne karakteristike su ispitane primenom različitih in vitro antioksidativnih, neuroprotektivnih, antitirozinaznih i antidijabetogenih testova. Primenom liofilizacije kao savremene tehnike sušenja i mikrotalasne ekstrakcije kao savremene ekstrakcione tehnike povećava se biopotencijal ispitivanih ekstrakata. Matični sok od plodova zove kao potencijalno novi funkcionalni proizvod je analiziran u cilju definisanja hemijskog, fitohemijskog i nutritivnog sastava, biološkog potencijala i senzorskih karakteristika. Ispitivanja dobijenog vina su bila usmerena na utvrđivanje optimalnih uslova za proizvodnju voćnog vina. Definisanjem hemijskog i fitohemijskog sastava i evaluacijom biopotencijala vina određen je optimalan temperaturni profil za dobijanje jednog od novih funkcionalnih proizvoda. Na osnovu utvrđenog hemijskog sastava etarsko ulje ploda i cveta zove se pokazalo kao potencijalno novi prirodni agens za održavanje svežine i produženja roka trajanja prehrambenih proizvoda. Zova je nesumnjivo samonikla biljna vrsta koja u budućnosti osnovano može biti polazna sirovina za kreiranje i dobijanje novih prehrmabenih proizvoda na domaćem i inostranom tržištu.
The main goal of this doctoral dissertation is to determine the chemical composition, biological and functional characteristics of new elderberry products. Elderberry products were obtained via traditional and modern technological processes. The exploitation of the natural potential of the elderberry started with the application of traditional and modern (lyophilization) drying techniques. To obtain high-value extracts of fruits and flowers, traditional (maceration) and modern (ultrasonic and microwave) extraction techniques with two solvents (50% ethanol and water) were applied. Obtaining the juice from the elderberry fruits implied the application of the traditional cold pressing method, whereas wine from the elderberry fruits was obtained in accordance with the standard procedure of wine production. The wine was exposed to different temperature treatments in different periods (60°C for 5 minutes, 60°C for 10 minutes, 70°C for 5 minutes and without heat treatment) to evaluate the biological activity of the product. The essential oil of the fruit and flower was obtained by hydrodistillation. The examination of the efficiency of the applied technological procedures of drying and extraction is based on observing the biological and functional characteristics of the obtained extracts of the said fruits and flowers. In the examined fruit and flower extracts, the dominant phenolic acids are chlorogenic and protocatechuic acid, while rutin and quercetin-3-O-hexoside are the dominant flavonoid compounds. Biological and functional characteristics were examined using various in vitro antioxidant, neuroprotective, antityrosinase, and antidiabetic tests. The application of lyophilization and microwave extraction (as modern drying and extraction techniques) increased the biopotential of the analyzed extracts. Elderberry juice, a potentially new functional product, was analyzed to define the chemical, phytochemical and nutritional composition, biological potential, and sensory characteristics. The wine was tested in order to determine the optimal conditions for the production of fruit wine. By defining the chemical and phytochemical composition and evaluating the biopotential of wine, the optimal temperature profile for obtaining one of the new functional products was determined. Based on the obtained chemical composition, it is determined that the essential oil of fruits and flowers is a potentially new natural agent for maintaining freshness and extending the shelf life of food products. Without a doubt, elderberry is a wild plant species that could be used in the future as the starting material for creating and obtaining new food products on the domestic and foreign markets.
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20

Miloš, Bjelica. "Uticaj kvaliteta semenki grožđa na bioaktivne komponente i održivost hladno presovanog ulja". Phd thesis, Univerzitet u Novom Sadu, Tehnološki fakultet Novi Sad, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110946&source=NDLTD&language=en.

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Abstract (sommario):
Podizanje novih zasada i povećanje kapaciteta preradegrožđa povećava količinu otpada sa kojim se suočavaindustrija proizvodnje vina i rakije. Najbolji i najodgovornijinačin upravljanja otpadom je njegovo dalje iskorišćenjekao nusproizvoda. U ovoj disertaciji sagledavana je mogućnost iskorišćenjanusproizvoda iz različitih faza proizvodnje u vinarijama idestilerijama za dobijanje semenki grožđa koje sukorišćene za proizvodnju hladno presovanog ulja. Hipotezase zasniva na činjenici da semenke grožđa raznih sorti izrazličitih faza proizvodnje vina (bela, roze ili crvena vina),odnosno, rakije mogu imati sasvim različit hemijski sastav ikvalitet koji svakako može da se reflektuje na kvalitet,bioaktivne komponente i održivost hladno presovanog ulja.Ovakav proizvod, obzirom da je dobijen hladnimpresovanjem, može biti veoma atraktivan za potrošače,zbog svojih specifičnih senzorskih i nutritivnihkarakteristika.Za potrebe izrade disertacije prikupljeni su nusproizvodii pripremljeni su uzorci iz vinarija i destilerija fruškogorskogvinogorja. Dobijene su semenke i proizvedeno hladnopresovano ulje od semenki crnog grožđa sorte Merlot,belog grožđa sorte Italijanski rizling i belog grožđa sorteSila, kao autohtone sorte vinove loze. Hladno presovanaulja su proizvedena od semenki grožđa koje nisu prošlenikakav tretman, odnosno dobijene su nakon presovanja,prilikom proizvodnje belih (Italijanski rizling i Sila) i roze(Merlot) vina, zatim od semenki koje su prošle procesfermentacije prilikom proizvodnje crvenih vina (Merlot) i odsemenki koje su prošle proces fermentacije i destilacijeprilikom proizvodnje rakije (Merlot, Italijanski rizling i Sila).Pored navedenih semenki i ulja, pripremljen je i prosečanproizvodni uzorak koji predstavlja uzorak dobijen od svihprikupljenih semenki. Kao uporedni uzorci korišćeno jenerafinisano i rafinisano ulje od semenki grožđa nabavljenona tržištu. Za realizaciju postavljenog cilja, rad na izvođenju ovedisertacije obuhvatio je različite faze. U prvoj faziprikupljene su semenke grožđa i ispitivane su njihovetehničko-tehnološke karakteristika i kvalitet. Zatim su odnavedenih semenki proizvedena hladno presovana ulja.U sledećim fazama, ovako dobijena uja, zajedno sauzorkom nerafinisanog i rafinisanog ulja od semenkigrožđa sa tržišta ispitivana su sa aspekta senzorskog inutritivnog kvaliteta i praćene su razlike u održivosti ulja.Izvršena je senzorska analiza, određivane su frakcijepigmenata, karotenoidi i hlorofili, merena je transparencija,a parametri boje ulja određivani su i instrumentalno.Nutritivni kvalitet ulja sagledavan je na osnovu sadržaja isastava bioaktivnih komponenti, pre svega tokoferola itokotrienola, fenola i sterola. Budući da ova jedinjenjaispoljavaju značajne antioksidativne aktivnosti izvršeno je iispitivanje antiradikalske aktivnosti uzoraka. Odživost uljaod semenki grožđa sagledana je na osnovu početnogkvaliteta i oksidativnog stanja, kao i rezultata ubrzanihtestova, kao što je Rancimat test, Schaal-oven test ifluorescentni test.Na osnovu dobijenih rezultata, može se konstatovati dasu svi dobijeni uzorci semenki imali dobru skladišnu vlagu,koja, obzirom na mali sadržaj ulja u semenkama, može daosigura čuvanje semenki u dužem periodu. Sadržaj ulja usemenkama, pored uticaja sorte vinove loze, zavisi i oduticaja procesa kome su podvrgnute semenke prepresovanja (fermentacija, destilacija).Senzorska analiza ulja od semenki grožđa pokazala jeznačajne razlike u karakteristikama koje su posledica nesamo načina dobijanja ulja (hladno presovano ili rafinisano), sorte vinove loze, već i postupka dobijanja,porekla i kvaliteta semenki grožđa. Uslovi kojima susemenke grožđa izložene u toku alkoholne fermentacije iposebno destilacije utiču na formiranje specifične aromehladno presovanog ulja. I pored toga što se pojavljujeizuzetno širok spektar različitih aroma, mirisa i ukusa u uljui što postoje značajne razlike u aromi ulja u zavisnosti odsorte grožđa, moguće je prepoznati da li je hladnopresovano ulje dobijeno od semenki grožđa bezfermentacije, posle fermentacije ili posle destilacije.Takođe, sa aspekta boje ulja može se kazati da rafinisanoulje od semenki grožđa ima svetlo žutu boju sazelenkastom nijansom, dok su hladno presovana uljaintenzivnijih boja i kreću se od žuto-zelenkaste, prekozelenkasto žute i svetlo zelenkaste do tamno zelene. Većiudeo zelene boje imaju hladno presovana ulja od semenkigrožđa dobijenih posle destilacije.U radu je pokazano da sadržaj pigmenata (karotenoida ihlorofila) u velikoj meri zavisi od porekla semenki.Postupak fermentacije doprinosi povećanju sadržajapigmenata, dok postupak destilacije, zbog visokihtemperatura ima negativan efekat.Transparencija uzoraka hladno presovanih ulja odsemenki grožđa proizvedenih za potrebe disertacije kretalase od 32,8% do 53,8%.Sadržaj nezasićenih masnih kiselina u svim uzorcimaulja od semenki grožđa veći je od 90%, pri čemudominantnu masnu kiselinu čini linolna, omega-6, masnakiselina.Sadržaj tokotrienola je veći od sadržaja tokoferola u uljima od semenki grožđa, a dominantni tokoferol je alfatokoferol.Njegov sadržaj je veći u uzorcima ulja dobijenimiz semenki nakon fermentacije i destilacije.Sadržaj fenolnih jedinjenja, u zavisnosti od sorte, uproseku je nešto viši u hladno presovanim uljima dobijenimod crvene sorte grožđa, ali uočava se i značajan porast(akumulacija) fenola u hladno presovanim uljima dobijenimiz semenki grožđa nakon procesa fermentacije i destilacije.Najveći pojedinačni sadržaju u ulju od semenki grožđa imaursolna kiselina, a pored nje značajniji sadržaj, madamnogo manji, pokazuju rezveratrol, kemferol i vanilinskakiselina.Najzastupljeniji steroli ulja semenki grožđa su β-sitosterol sa udelom od 62,59-69,74%, stigmasterol saudelom od 12,13-15,00% i kampesterol sa udelom od 6,59-11,94% u ukupnim sterolima. Na sadržaj fitosterola uuljima od semenki grožđa nemaju uticaja procesifermentacije i destilacije kojima su podvrgnute semenkepre preosvanja.U radu je dokazan negativan uticaj procesa fermentacijei destilacije kojima su povrgnute semenke grožđa naantiradikalski potencijal dobijenih ulja. Antiradikalskipotencijal ulja od semenki grožđa zavisi i od sorte vinoveloze, kao i od načina dobijanja ulja (hladno presovano ilirafinisano).Procesi fermentacije i destilacije utiču i na osnovnihemijski kvalitet dobijenih hladno presovanih ulja na načinda dovode do povećanja kiselinskog i peroksidnog broja.Hladno presovana ulja od semenki grožđa pokazujudobru oksidativnu stabilnost. Rancimat test je pokazao razlike u indukcionom periodu hladno presovanih ulja odsemenki grožđa kao posledicu razlike u sorti, kao i unačinu dobijanja semenki. Proces fermentacije utiče napovećanje, a proces destilacije na smanjenje indukcionogperioda.Na osnovu svih dobijenih rezultata istraživanja može sekonstatovati da su hladno presovana ulja od semenkigrožđa pokazala različit nutritivni kvalitet i oksidativnustabilnost, zbog specifičnih razlika koje su posledica razlikau sorti i poreklu semenki, tj. zbog specifičnog efektafermentacije i destilacije na semenke od kojih je uljeproizvedeno, čime je i potvrđena hipoteza.
Raising new plantations and increasing the grapeprocessing capacity increases the amount of waste facedby the wine and brandy industry. The best and mostresponsible way of waste management is its furtherexploitation as by-products.In this dissertation, the possibility of using by-products from different stages of production in wineries and distilleries forobtaining grape seeds, which were used for the productionof cold pressed oil, was examined. The hypothesis isbased on the fact that grape seeds of various varietiesfrom different stages of wine production (white, rose or redwine), that is, brandy can have a completely differentchemical composition and quality that can certainly bereflected on the quality, bioactive components and stabilityof cold pressed oil.Such a product, as it is obtained by cold pressing, canbe very attractive to consumers, due to its specific sensoryand nutritional characteristics.For the needs of the dissertation, the by-products werecollected and samples were prepared from the wineriesand distilleries of the Fruška Gora vineyard. Seeds wereobtained and cold pressed oil produced from Merlot grapeseed, as representatives of red grape varieties, ItalianRiesling, as representatives of white grape varieties andSila, as new white grape varieties. Cold pressed oils wereproduced from grape seeds that did not undergo anytreatment, that is, they were obtained after pressing, duringthe production of white (Italian Riesling and Sila) and rose(Merlot) wines, then from the seeds that were fermentedduring the production of red wines (Merlot ) and seeds thathave undergone fermentation and distillation processduring the production of brandy (Merlot, Italian Riesling andSila). In addition to the mentioned seeds and oils, anaverage production sample was prepared, which is asample obtained from all collected seeds. Unrefined andrefined grape seed oil purchased on the market was usedas comparative samples. For realization of the set goal, the work on theperformance of this dissertation encompassed differentphases. In the first phase, grape seed were collected andtheir technical and technological characteristics and qualitywere examined. Then cold-pressed oils were producedfrom these seeds.In the following phases, the resulting ear, together with asample of unrefined and refined grape seed oil from themarket, were examined from the aspect of sensory andnutritional quality and differences in oil stability wereobserved. Sensory analysis was performed, pigmentatefractions, carotenoids and chlorophylls were determined,transparency was measured, and oil color parameterswere also determined instrumentally. The nutritive oilquality was examined based on the content andcomposition of bioactive components, primarily tocopherolsand tocotrienols, phenols and sterols. Since thesecompounds exhibit significant antioxidant activities, theantiradical activity of the samples was also tested. Thestability of grape seed oils was examined based on theinitial quality and the oxidative state, as well as the resultsof accelerated tests, such as Rancimat test, Schaal-ovenand fluorescence test.On the basis of the obtained results, it can be concludedthat all the obtained seed samples had good storagemoisture, which, given the small content of oil in the seeds,can ensure the storage of seeds for a longer period. Thecontent of oil in the seed, in addition to the influence of thegrape variety, depends on the influence of the process towhich the seeds are subjected to pressing (fermentation,distillation). Sensory analysis grape seed oils showed significantdifferences in characteristics that are due not only to themethod of obtaining oil (cold pressed or refined), grapevarieties, but also the method of obtaining, the origin andquality of grape seed. The conditions for grape seedsexposed during fermentation and especially distillationaffect the formation of a specific cold pressed oil. Althoughan extremely wide range of different flavors, odors andflavors in oil appear, and there are significant differences inthe aroma of the oil, depending on the grape variety, it ispossible to recognize whether the cold-pressed oil isderived from the grape seed without fermentation, afterfermentation or after distillation. Also, from the aspect of oilcolor it can be said that refined grape seed oil has a lightyellow color with a greenish shade, while cold pressedgrape seed oils have more intense colors range fromyellowish-greenish, over greenish yellow and light greenishto dark green. A higher proportion of green color has coldpressed grape seed oils obtained after distillation.The thesis has shown that the content of pigments(carotenoids and chlorophyll) depends to a great extent onthe origin of the seed. The fermentation processcontributes to increasing the content of pigments, while thedistillation process has a negative effect due to hightemperatures.Transparency of cold pressed grape seed oils producedfor the dissertation ranged from 32.8% to 53.8%.The content of unsaturated fatty acids in all samples ofgrape seed oil is greater than 90%, with the dominant fattyacid being linoleic, omega-6, fatty acid. The content of tocotrienols is higher than the content oftocopherols in grape seed oils, and the dominanttocopherol is alpha-tocopherol. Its content is higher in oilsamples obtained from the seed after fermentation anddistillation.The content of phenol compounds, depending on thevariety, is somewhat higher in cold pressed oils obtainedfrom red grape varieties, but there is also a significantincrease in accumulation of phenol in cold pressed oilsobtained from the grape seed after the fermentation anddistillation process. The largest individual oil content ofgrape seeds has ursolic acid, and besides it, significantcontent, although much smaller, shows rezveratrol,kemferol and vanillinic acid.The most prevalent sterols of grape seed oils are β-sitosterol with a share of 62.59-69.74%, stigmasterol with ashare of 12.13-15.00% and campesterol with a share of6.59-11.94% in total sterols. Fermentation and distilationprocesses, to which the seeds have been exposed, haveno effect on the content of phytosterols in grape seed oils.The paper has shown the negative influence of thefermentation and distillation process, to which the seedshave been exposed, onto the antiradical potential of theobtained oils. The antiradical potential of grape seed oilsdepends on grape varietes, as well as on the way oil isobtained (cold pressed or refined).Processes of fermentation and distillation also affect thebasic chemical quality of obtained cold pressed oils in sucha way as to increase the acid and peroxide values.Cold pressed grape seed oils show good oxidative stability. The Rancimat test showed differences in theinduction period of cold pressed grape seed oils as a resultof the variation in the variety, as well as in the method ofobtaining the seed. The fermentation process affects theincrease, and the process of distillation decreases theinduction period.Based on all the obtained results, it can be concludedthat cold pressed grape seed oils showed differentnutritional quality and oxidative stability due to specificdifferences resulting from differences in variety and seedorigin, i.e. due to the specific effect of fermentation anddistillation processes on the seeds from which the oil wasproduced, thus confirming the hypothesis.
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21

Ulate, Edith [Verfasser]. "Investigation into the presence of orthologues of the putative cyclooctadepsipeptide receptor HC110-R in Toxocara canis and Ancylostoma caninum / von Edith Ulate". 2005. http://d-nb.info/98190615X/34.

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