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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Pašarų organinės medžiagos virškinamumo priklausomybė nuo karvių didžiojo prieskrandžio turinio fermentacijos lygio / The dependence of organic material digestion of forage on the level of cows’ long prestomach fermentation

Ruseckaitė, Irena 18 March 2008 (has links)
Bandymas atliktas siekiant ištirti didžiojo prieskrandžio biocheminius ir mikrobiologinius rodiklius, šeriant karves skirtingos sudėties racionais; įvertinti didžiojo prieskrandžio fermentacinį aktyvumą; ištirti žolinių pašarų – šieno, šienainio, kukurūzų siloso virškinamumą in vitro, inkubuojant juos su skirtingo fermentacinio aktyvumo didžiojo prieskrandžio turiniu. Iš gautų rezultatų galime teigti, kad skirtingos sudėties racionai turi įtakos karvių didžiojo prieskrandžio turinio mikrobiologiniams ir biocheminiams rodikliams. Nustatyta, kad I (kontrolinės) grupės karvių didžiojo prieskrandžio turinio ph buvo 10,5 proc. (p<0,0001) mažesnis; redukcinis bakterijų aktyvumas vyko 131 s (p<0,0001) greičiau; gliukozės rūgimo reakcija buvo 71,4 proc. (p<0,0001) didesnė; pirmuonių rasta 120 103/ (p<0,0001) daugiau; LRR gamyba padidėjo 27,2 proc. palyginant su II (bandomosios) grupės karvėmis, kurios buvo šeriamos nesubalansuotu racionu. Subalansuoto raciono įvairesni ir maistingesni pašarai nulėmė, kontrolinės grupės aktyvesnį didžiojo prieskrandžio turinio fermentacinį procesą. Subalansuotame racione vyravo šienainis (55 proc.), kukurūzų silosas (20 proc.) ir kombinuotieji pašarai (20,7 proc.). Racionas buvo praturtintas melasa (0,62 proc.) ir BVMP (0,37 proc.). Bandomosios karvės iš sultingųjų pašarų gavo tik kukurūzų siloso, kuris ir sudarė didžiausią raciono dalį (75 proc.). Jų racione nebuvo šienainio, kuris yra 2-3 kartus maistingesnis palyginti su kukurūzų silosu (2... [toliau žr. visą tekstą] / Aim of thesis: to analyse the dependence of forage organic material digestion on the level of cows’ long prestomach fermentation. Tasks: 1. To estimate biochemical and microbiological factors of large prestomach content of cows, fed by different consist rations and to evaluate fermentational activity; 2. To examine herby forage- hay, haylage and maize silage- organic material digestion in vitro by incubating them with different fermentational activity content of long prestomach. In the course of work the following was identified: 1. Ph of long prestomach content of cows fed by balanced ration was 10,5 % (p<0,0001) lower, the reaction of bacteria reductional activity was 131 s (p<0,0001) faster, the reaction of glucoses fermentation was 71,4 % (p<0,0001) higher, protoza was found 120 103 / ml (p<0,0001) more, the production of free fatty acids increased by 27,2 % (p<0,0001) in comparison with cows, which were fed by unbalanced ration. 1.1. Therefore fermentational processes of long prestomach of cows fed by balanced ration were active, and of those fed by unbalanced ration- slowed down. 2. When incubating hay, haylage and silage in vitro with different fermentational activity content of long prestomach, organic material digestion (OMD) of all examined forage was highest by incubating them with active fermentation long prestomach content: 2.1. organic material digestion (OMD) was of hay 5,52 % (p<0,0001) higher; organic material digestion (OMD) was of haylage 5,5 % (p<0,0001)... [to full text]
2

Izučavanje intermedijera u fermentaciji rafinoze i melibioze kvascima / STUDY OF INTERMEDIATE COMPOUND INYEAST FERMENTATION OF RAFFINOSE AND MELIBIOSE

Markov Siniša 26 December 1996 (has links)
<p><strong>Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).</strong></p><p>Analizom podloge iz standardizovanog fiziolo&scaron;kog testa fermentacije rafinoze<br />primenom HPTLC metode, utvrđeno je da se u podlozi javlja jedinjenje sa<br />retencijom većom od rafinoze, dok svi konstituenti rafinoze imaju manju retenciju.<br />Za nastajanje takvog jedinjenja tokom testa fermentacije rafinoze i njenih<br />konstituenata kvascima nije bilo literatume potvrde.<br />Ispitivano je kod kojih kvasaca i kod fermentacije kojih ugljenih hidrata se u<br />podlozi javlja ispitivano jedinjenje. Zatim je ispitivana veza određenih parametara<br />procesa fermentacije sa nastajanjem zapaženog jedinjenja. Pored toga, ispitivanom<br />jedinjenju su, nakon izolovanja iz fermentacione podloge i preči&scaron;ćavanja radi<br />dobijanja čiste supstance, određeni neki elementi strukture.<br />Utvrđeno je da se samo kod kvasaca koji imaju fiziolo&scaron;ko svojstvo fermentacije<br />celog molekula rafinoze i svojstvo fermentacije melibioze tokom procesa<br />javlja ispitivano jedinjenje i da je ono intermedijer metabolizma. Činioci značajni<br />za proces fermentacije - inokulum (količina i podloge za njegovu pripremu),<br />sastav podloge (sadržaj rafinoze i melibioze, kao i različiti izvori azota) i uslovi<br />gajenja, varirani u odnosu na standardizovani fiziolo&scaron;ki test fermentacije, ne<br />prouzrokuju promenu kvalitativnog sastava jedinjenja u podlozi tokom fermentacije<br />rafinoze i melibioze. Dakle, ispitani intermedijer je uvek prisutan u podlozi.<br />Na povećanje njegovog sadržaja u podlozi utiče dodatak galaktoze tokom fermentacije<br />rafinoze. Najveća koncentracija ispitivanog intermedijera (0,87 mg/ml) je<br />trećeg dana fermentacije melibioze, odnosno drugog dana fermentacije rafinoze<br />(1,48 mg/ml). Sadržaj ispitivanog intermedijera na kraju procesa fermentacije<br />rafinoze je 6 puta veći nego kod melibioze (1,04 prema 0,17 mg/ml). Ispitivani<br />intermedijer je redukujući ugljeni hidrat molekulske mase 504 &scaron;to odgovara<br />trisaharidima. Konstituenti ovog jedinjenja su glukoza i galaktoza koje su povezane<br />najverovatnije a-tipom veze.</p> / <p><strong>Abstract was processed by technology for Optical character recognition (OCR).</strong></p><p>Analyzing the media from standardized physiological test for raffinose fermentation<br />by means of HPTLC method, the appearance of a compound was registered<br />with retention higher than that of raffinose or its constituents indicating also<br />smaller retentions. No literature data were found for the formation of such a<br />compound during fermentation tests for raffinose and its constituents.<br />It was investigated which yeast will indicate formation of the investigated<br />compound in the course of fermentation as well as which carbohydrate during its<br />fermentation will indicate the presence of this compound. Further investigation<br />included correlation of particular parameters known as significant for the process<br />of fermentation, with the appearance of the noticed compound. Moreover, some<br />structural elements were also determined for the investigated compound, after<br />isolation from fermentation media and purification in order to obtain pure<br />substance.<br />It was proved that the investigated compound appeared just with the yeasts<br />physiologically characterized by fermentation of entire molecule of raffinose as<br />well as melibiose in the course of fermentation. Ibis compound proved to be an<br />intermediate compound of metabolism. Parameters significant for the process of<br />fermentation - inoculum (size and media for its growth), media composition<br />(content of raffinose and melibiose as different nitrogen source) and the condition<br />of incubation, exchanged from the standardized physiological test of fermentation,<br />didn&#39;t change qualitatively the compound composition in the media during<br />raffinose and melibiose fermentation. Therefore, it is obvious that the investigated<br />intermediate compound was present constantly in the media. Its content is<br />effected by the addition of galactose in the course of raffinose fermentation. The<br />highest concentration (0.87 mg/ml) of the investigated compound was registered<br />on the third day of melibiose fermentation, i.e. the second day of raffinose<br />fermentation (1.48 mg/ml). Content of the investigated intermediate compound<br />at the end of raffinose fermentation was six limes higher than of melibiose (1.04<br />in relation to 0.17 mg/ml). The investigated intermediate compound proved to be<br />the reduced carbohydrate with molecular mass of 504 corresponding to trisaccharides.<br />Constituents of this compound, glucose and galactose are probably connected<br />by a-type of bonds.</p>
3

PROMENE KOMPONENATA I STRUKTURE MLEKA TOKOM FERMENTACIJE DODATKOM NEKONVENCIONALNOG STARTERA / CHANGES OF MILK COMPONENTS ANDSTRUCTURE DURING FERMENTATION PROCESS BY NON–CONVENTIONAL STARTER

Kanurić Katarina 29 December 2014 (has links)
<p>Promene komponenata i strukture mleka ispitane su tokom fermentacije kori&scaron;ćenjem inokuluma kombuhe kultivisane na crnom čaju zaslađenom saharozom<br />u koncentraciji 10%. Fermentacija mleka sa 2,2% mlečne masti izvr&scaron;ena je na dve različite temperature (37&deg;C i 42&deg;C) i uzorci su analizirani na sledećim pH vrednostima: 6,1; 5,8; 5,4; 5,1; 4,8 i 4,6. Urađena je determinacija i identifikacija produkata fermentacije laktoze kao &scaron;to su: &scaron;ećeri, organske kiseline i masne kiseline. Ispitane su teksturalne i reolo&scaron;ke karakteristike i mikrostruktura uzoraka. Pored toga, utvrđene su sličnosti i razlike uticaja inokuluma kombuhe na proces fermentacije mleka u poređenju sa delovanjem jogurtne, odnosno probiotske starter kulture.<br />Tokom fermentacije mleka u različitim fazama procesa pri odabranim pH vrednostima na 42&deg;C transformi&scaron;e se 14,6% laktoze odnosno 18,2% na 37&deg;C. Sadržaj galaktoze i glukoze koje nastaju fermentacijom i hidrolizom laktoze raste između prve i druge tačke fermentacije (pH=6,07 i pH=5,8). Dominantne organske kiseline tokom fermentacije su L&ndash;mlečna kiselina i sirćetna kiselina. Nije utvrđena značajna razlika u sadržaju masnih kiselina tokom fermentacije mleka kombuhom na 37&deg;C i 42&deg;C. Sadržaj palmitinske kiseline u mleku i uzorcima tokom fermentacije je najveći, zatim slede miristinska, stearinska i oleinska kiselina.<br />Praćenjem procesa fermentacije mleka uz primenu kombuhe na 37&deg;C i 42&deg;C od početne pH vrednosti 6,07 do zavr&scaron;ne 4,6, najznačajnije promene teksturalnih karakteristika (čvrstoće, konzistencije, kohezivnosti i indeksa viskoziteta) i reolo&scaron;kih svojstava zabeležene su između pH=5,4 i 5,1, &scaron;to je u korelaciji sa mikrostrukturom.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Promene viskoziteta u svim uzorcima pokazuju istu regresionu liniju, sa različitim koeficijentima i visokom vredno&scaron;ću r2, osim uzorka proizvedenog primenom jogurtne kulture na pH 5,4. Uzorak dobijen kori&scaron;ćenjem inokuluma kombuhe imao je najveće vrednosti kompleksnog modula, &scaron;to je rezultiralo boljim reolo&scaron;kim karakteristikama gotovog proizvoda.<br />Da bi se definisao empirijski model procesa fermentacije laktoze u mleku delovanjem kombuhe formulisana su prethodno dva matematička modela za kinetiku fermentacije saharoze u tradicionalnom kombuha napitku (na crnom čaju) &ndash; jedan koji opisuje promenu koncentracije saharoze tokom fermentacije, i drugi koji opisuje brzinu fermentacije. Promena koncentracije laktoze na ispitivanim temperaturama 37&deg;C i 42&deg;C sastoji se od dve lag faze između kojih je faza izraženog pada koncentracije. Krive zasićenja pokazuju sigmoidalnu kinetiku na nižim koncentracijama laktoze, ukazujući na kompleksni ne&ndash;Michaelis&ndash;Mentenov tip kinetike.<br />Generalno može se istaći da su primenom inokuluma kombuhe tokom fermentacije mleka u različitim fazama procesa ustanovljene specifične promene komponenata i strukture u poređenju sa efektima delovanja jogurtne odnosno probiotske starter kulture.</p><p>&nbsp;</p> / <p>Changes of milk components and structure were examined during fermentation by kombucha inoculum cultivated on black tea switened with saccharose in a concentration of 10%. The fermentation of milk with 2.2% of milk fat was carried out at two different temperatures (37&deg;C i 42&deg;C) and samples were analyzed at the following pH values: 6.1; 5.8; 5,4; 5.1; 4.8 and 4.6. Determination and identification of the lactose fermentation products, such as: sugars, organic acids and fatty acids were carried out. Textural and rheological characteristics and microstructure of the samples were investigated. Furthermore, the effect of kombucha on the milk fermentation process was compared with the effect of yoghurt and probiotic starter culture.<br />During milk fermentation at various stages of the process 14.6% of lactose content was transformed at 42&deg;C and 18.2% at 37&deg; C. The galactose and glucose content, which are formed by lactose hydrolyses and fermentation, increased between first and second pH point of fermentation (pH = 6.07 and pH = 5.8). Dominant organic acids during fermentation are L&ndash;lactic acid and acetic acid. There is no significant difference between samples in fatty acids content during fermentation on 37&deg;C and 42&deg;C. The level of palmitic acid in milk and samples was the highest of all fatty acids, followed by myristic, stearic, and oleic acid.<br />The most significant changes in textural properties (firmness, consistency, cohesiveness and viscosity index) and viscosity during milk fermentation by kombucha at 37&ordm;C and 42&deg;C, from the initial pH value 6.07 to a final 4.6, were recorded between pH=5.4 and 5.1, which is in correlation with microstructure.<br />Viscosity changes in all samples showed the same regression line with the different coefficients and a rather high r2 except for the sample produced with standard yoghurt culture at the pH 5.4. Samples produced with kombucha had the highest values of the complex modulus, which indicates better rheological characteristics of the final product.<br />In order to define an empirical model of lactose fermentation process in milk by kombucha, two mathematical models (one for the change of saccharose concentration, during its fermentation by kombucha, and the other for the rate of the mentioned fermentation) previously were formulated. Change of lactose concentrations at 37&ordm;C and 42&ordm;C consists of two retaining stages and very steep descend in-between. Saturation curves show a sigmoidal kinetics at low lactose concentrations, indicating a complex non&ndash;Michaelis&ndash;Menten type kinetics.<br />Generally it can be concluded that specific changes in the components and structure of milk by application of kombucha inoculum during fermentation at different stages of the process were established in comparison with the effects of yoghurt and probiotic starter culture.</p>
4

Proizvodnja i ocena kvaliteta voćnog vina od sorti domaće šljive (Prunus domestica L.) / Production and quality assessment of fruit wines from native plum (Prunus domestica L.) varieties

Miljić Uroš 06 April 2015 (has links)
<p>Cilj ove doktorske disertacije je bio da se oceni mogućnost upotrebe tri sorte domaće &scaron;ljive, različitih epoha sazrevanja (Čačanska rana, Čačanska lepotica i Požegača), kao sirovina za proizvodnju voćnog vina. Utvrđeni mehanički sastav plodova i hemijske karakteristike kljuka i soka ispitivanih sorti &scaron;ljive ukazuju da se čačanska lepotica i Požegača mogu smatrati boljim sirovinama za proizvodnju voćnog vina u odnosu na sortu Čačanska rana. Vr&scaron;ena je optimizacija uslova alkoholne fermentacije (temperature, vrednosti pH, trajanja fermentacije i doze enzimskog preparata), u sklopu koje je, takođe, ispitana i upotreba različitih pektolitičkih enzima za tretman kljuka i ocenjen uticaj upotrebe različitih sojeva kvasaca, kao proizvodnih mikroorganizama, na kvalitet vina od &scaron;ljive. Utvrđeno je da, među ispitanim proizvodnim organizmima, kvasac Spriferm (S. cerevisiae) daje vino od &scaron;ljive najboljeg kvaliteta. Postupkom numeričke optimizacije dobijene su sledeće vrednosti procesnih parametara fermentacije vina od &scaron;ljive: temperatura 25 &deg;C, vrednost pH 3,5 i doza pektolitičkog enzima 0,5 g/100 kg. Pri navedenim uslovima dobijeni fitovani modeli predviđaju prinos etanola od 7,5% v/v, prinos glicerola od 5g/l, prinos vina od 48% (48 ml vina na 100 g kljuka) i formiranje 710 mg/l metanola. Karakterizacija proizvedenog vina od &scaron;ljive podrazumevala je određivanje sadržaja najvažnijih sastojaka: alkohola, kiselina, mineralnih materija, fenolnih i aromatičnih jedinjenja, kao i ocenu njegovih funkcionalnih karakteristika (antiradikalske, antimikrobne i antiproliferativne aktivnosti). Na kraju, ocenjena je mogućnost smanjenja produkcije metanola u vinu od &scaron;ljive primenom različitih fizičko-hemijskih tretmana kljuka. Utvrđena je značajno veća efikasnost postupaka koji uključuju neki vid toplotnog tretmana kljuka u odnosu na postupke koji podrazumevaju upotrebu određenog enolo&scaron;kog sredstva.</p> / <p>The aim of this PhD thesis was to assess the possibility of using three native plum varieties, with different ripening periods (Ĉaĉanska rana, Ĉaĉanska lepotica and Poņegaĉa), as raw material for the production of fruit wines. Determined mechanical composition and chemical characteristics of fruit pomace and juice indicate that the Ĉaĉanska lepotica and Poņegaĉa are considered as better raw materials for the production of fruit wine compared to Ĉaĉanska rana. Optimization of fermentation conditions (temperature, pH, the duration of fermentation and the dose of pectolytic enzyme) was conducted. This step also included investigation of the different pectolytic enzymes use for the treatment of pomace and evaluated the impact of using different yeast strains, as well as the effect of different production microorganisms on the plum wine quality. It was found that, among the tested production microorganisms, Spriferm (S. cerevisiae) yeast gives the plum wine of best quality. Numerical optimization procedure resulted with the following values of the process parameters of plum wine fermentation: temperature 25 &deg;C, pH value 3.5 and pectolytic enzyme dose of 0.5 g/100 kg. Under these conditions the obtained fitted models predict the ethanol yield of 7.5% v/v, glycerol yield 5 g/l, the wine yield of 48% (48 ml from 100 g of pomace) and the formation of 710 mg/l of methanol. Characterization of the produced plum wines included the determination of the most important ingredients: alcohol, acids, minerals, phenolic and aromatic compounds, as well as evaluation of their functional characteristics (antiradical, antimicrobial and antiproliferative activities). Finally, the possibility of reducing the methanol production in plum wine was estimated by applying different physico-chemical treatments of the pomace. Significantly higher efficiency of procedures that involve some form of heat treatment of pomace, compared to treatments which involve the use of certain oenological means, was observed.</p>
5

Biokatalizatorių įtaka akrilamido formavimuisi ruginės duonos gaminiuose bei kvietinių miltų technologinių savybių pagerinimo galimybės RS 190 modifikuotomis mielėmis, taikant pastaruosius pusruginės duonos gamybai / Impact of biocatalysts on the formation of acrylamide in rye bread products and improvement possibilities of technological properties of wheat flour by genetically modified yeast RS 190 by applying the latter for semi-rye bread making

Krunglevičiūtė, Vita 18 June 2013 (has links)
Darbo tikslas buvo įvertinti biokatalizatorių įtaką akrilamido formavimuisi ruginės duonos gaminiuose bei RS 190 modifikuotų mielių įtaką kvietinių miltų 550 C tipo technologinių savybių pagerinimui, pritaikant juos pusruginės duonos gamybai. Nustatyta, kad L. delbruecki intensyviau mažina terpės pH (3,35) nei P. acidilactici (4,32), tačiau, žaliavos apcukrinimui naudojant gliukoamilolitinius fermentus, fermentacijos procesą galima suintensyvinti. Žaliavos apcukrinimas fermentais įtakoja didesnį P. acidilactici proteolitinių fermentų aktyvumą rauguose. L. delbruecki fermentuoti kepiniai gaunami geresnės kokybės nei fermentuoti P. acidilactici. P. acidilactici fermentuotų kepinių kokybę galima pagerinti naudojant optimalų gliukoamilazės kiekį (0,05 ml). 0,030 ml gliukoamilazės panaudojimas žaliavos apcukrinimui, lėtina kepinių žiedėjimą (minkštimo struktūra pakito: su 0,03 ml – 2,15, su 0,05 ml – 2,54 karto). Akrilamido formavimuisi turi įtakos ne tik fermentacijai naudotos PRB, bet ir kepinio dydis (500 g kepiniuose vidutinis akrilamido kiekis 61,55 µ/kg, 1000 g - 40,48 µ/kg). Tirtų kvietinių miltų fizikinės struktūrinės savybės yra tinkamos mielinių kepinių gamybai, o modifikuotų mielių priedas yra tinkama priemonė kvietinių kepinių kokybės rodikliams pagerinti. 550 C tipo kvietinius miltus su modifikuotų mielių priedu panaudojus pusruginių kepinių gamybai galima pagerinti kepinių akytumą ir padidinti drėgnį, tačiau, kitos savybės nepakinta, arba gaunamos prastesnės. Šis... [toliau žr. visą tekstą] / The goal of the thesis was to assess the impact of biocatalysts on the formation of acrylamide in rye bread and to determine the impact of genetically modified yeast RS 190 on improvement of technological properties of wheat flour 550 C by applying them for semi-rye bread making. It has been established that L. delbruecki decreases pH (3,35) medium more intensively than P. acidilactici (4,32), however by using glucoamylolytic enzymes for scald making fermentation process may be intensified. The use of enzymes for scald production results in a better activity of P. acidilactici proteolytic enzymes in leaven. L. delbruecki fermented bread are received of a better quality than fermented P. acidilactici. The quality of P. acidilactici fermented bread may be improved by using an optimum amount of glucoamylase (0,05 ml). Using of 0,030 ml glucoamylase for the scald producion slows staling process of bread (structure of the crumb changed as follows: with 0,03 ml – 2,15, with 0,05 ml – 2,54 times). The formation of acrylamide is influenced not only by lactic acid bacteria (LAB) used for fermentation, but also, by the size of bread (in 500 g pastry goods – midle acrylamide content61,55 µ/kg, in 1000 g - 40,48 µ/kg) as well. Physical structural properties of investigated wheat flour are suitable for making bread, whereas genetically modified yeast supplement is a suitable means for improvement of quality indicators of wheat bread. By using 550 C type wheat flour with... [to full text]
6

Galvijų didžiojo prieskrandžio fermentacinio aktyvumo rodikliai ir organinės medžiagos virškinamumas in vitro / Indicators of the rumen fermentation activity of cattle and organic matter digestibility in vitro

Čiurilaitė, Agnė 05 March 2014 (has links)
Darbo tikslas buvo įvertinti didžiojo prieskrandžio turinio fermentacinių procesų aktyvumą ir nustatyti pašarų organinės medžiagos (OM) virškinamumą in vitro. Tyrimai atlikti su 9 Lietuvos juodmargių veislės karvėmis tvartiniu laikotarpiu. Didžiojo prieskrandžio turinys buvo paimtas ryklės-stemplės zondu GDZ-1 po rytinio šėrimo. Didžiojo prieskrandžio turinio rodikliai buvo fiziologinės normos ribose: pH buvo vidutiniškai 6,48 ± 0,21, redukcinis bakterijų aktyvumas – 114,2±41,06 s, gliukozės rūgimo reakcijos greitis – 1,69±0,71 cm3/h, LRR 98,33±12,06 mmol/l ir pirmuonių skaičius 226,2±48,63×103/ml. Inkubuojant pašarus su tiriamų karvių didžiojo prieskrandžio turiniu in vitro, nustatėme, kad siloso OM virškinamumas buvo 10,2 ir 36,4 proc. (p<0,001) didesnis nei atitinkamai šieno ir šiaudų. Šieno OM virškinamumas buvo 29,2 proc. didesnis nei šiaudų (p<0,001). / The goal of the study was to evaluate the level of activity of the rumen fermentation processes and determine the digestibility of organic matter (OM) of the feed in vitro. The researches were carried out with 9 Lithuanian Black-and-White cows during the indoor period. The rumen fluid was obtained by using a GDZ–1 pharyngeal and esophageal probe after the morning feeding. The tested physiological parameters of the contents of the rumen were within the normal range: pH was 6.48 ± 0.21 in average, the reduction activity of bacteria was 114.2 ± 41.06 s, the glucose fermentation reaction time was 1.69 ± 0.71 cm3/h, the free fatty acids (FFA) were equal to 98.33 ± 12.06 mmol/l and the number of protozoa was 226.2 ± 48.63 × 103/ml. During the incubation of the feed with the contents of rumen of the studied cows in vitro, we determined that the OM digestibility of silage was 10.2 and 36.4 per cent (p<0.001) which was higher than that of hay and straw. The OM digestibility of hay was higher by 29.2 per cent compared to the straw (p<0.001).
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Mikologiniai ir mikotoksikologiniai tyrimai ekologiškoje ir įprastinėje duonos gamybos grandinėje panaudojant pienarūgštes bakterijas deoksinivalenolio detoksikacijai / Fungical and toxicological research in organic and tradicional bread production chain using lactic acid bacteria for deoxynivalenol detoxification

Gervytė, Vesta 18 June 2014 (has links)
Šio darbo tikslas: Nustatyti, įvertinti ir palyginti ekologiškoje ir įprastinėje grūdinėje žaliavoje mikologinį ir mikotoksikologinį užterštumą, panaudojant pienarūgštes bakterijas deoksinivalenolio detoksikacijai. Darbo uždaviniai: Ištirti, įvertinti ir palyginti ekologiniuose ir įpratiniuose ūkiuose surinktų grūdų mikologinį ir mikotoksikologinį užterštumą. Įvertinti ir palyginti kvietinių ir ruginių miltų mikotoksikologinį užretštumą. Įvertinti fermentacinių procesų įtaką DON kiekiui duonos gamybos grandinėje Naudota metodika: Mikromicetų skaičius įvertintas pagal LST ISO 6611:2004. Mikromicetų rūšys identifikuotos vadovaujantis apibūdintojais (Samson et al., 2000; Lugauskas ir kt., 2002). Mikotoksinų koncentracija nustatyta imunofermentinės analizės metodu (IFA), panaudojus komercinius VERATOX® DON 5/5, (Neogen, JAV) rinkinį. Fermentacija atlikta panaudojus pieno rūgšties bakterijų kultūrą L. sakei. Tyrimų rezultatai pateikti panaudojus R statistinį paketą. Išvados: Ištyrūs kviečius ir rugius surinktus iš ekologinių ir iprastinių ūkių daugiausia dominavo Fusarium spp. genties mikromicetai. Potencialūs deoksinivalenolio producentai. Gyvybingų sporų skaičius 33 proc. didesnis nustatytas kviečiuose surinktuose iš ekologinių ūkių (p<0,05). Lyginant rugių mėginius, gyvybingų sporų skaičius 29,5 proc. didesnis nustatytas taip pat ekologiniuose ūkiuose surinktuose rugiuose 44±2,1x102 KSV/g (p<0,05). Palyginus gyvybingų sporų skaičių kvietiniuose ir ruginiuose miltuose 5... [toliau žr. visą tekstą] / Objective of the thesis: To identify, evaluate and compare mycological and mycotoxicological contamination in ecological and standard grains by using lactic acid bacteria for deoxynivalenol detoxification. Tasks: Investigate, evaluate and compare mycological and mycotoxicological contamination of grains collected in ecological and standard farms. Evaluate and compare mycotoxicological contamination of wheat and rye flour. Evaluate influence of fermentation processes on DON level in bread production chain. Research methodology: The total count of microorganisms (CFU/g-1) in the analysed sample was determined by way of dilution using the nutrient agar. LST ISO 6611:2004. Micromycete content was determined according to the method of enzyme-linked immunosorbent assay (ELISA) by using the commercial VERATOX® DON 5/5, (Neogen, JAV). Fermentation processes using latic acid bacteria L. sakei. The results of the data analysis and research presented using the R statistical package. Results and discussion: After examining wheat and rye that were collected from ecological and standard farms, it was noticed that mycromycetes of Fusarium spp. genus dominated mostly. Potential Deoxynivalenol Prudecents. Wheat that was collected from ecological farms had 33 proc. higher number of viable spores, i.e. (p<0,05). Similarly, the number of viable spores of rye was 29.5 proc. higher in the rye that was collected in the ecological farms, i.e. 44±2,1x102 CFU/g (p<0,05). (CFU-Colony forming... [to full text]
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Primena tehnoloških postupaka spontane fermentacije i osmotske dehidratacije za unapređenje nutritivnog profila, senzornih svojstava i održivosti kupusa / The application of technological processes of spontaneous fermentation and osmotic dehydration for improving the nutritional profile, sensory characteristics and viability of cabbage

Cvetković Biljana 24 December 2014 (has links)
<p>U ovom radu je obrađen postupak spontane fermentacije tradicionalnog proizvoda, fermentisanog kupusa u glavicama. U prvom delu urađena je karakterizacija domaće tradicionalne populacije Futo&scaron;ki u odnosu na uvozni hibrid Bravo. Na osnovu PCA analize i analize standardnih ocena SS fizičkih, hemijskih i senzorskih paramentara odabrani su uzorci povoljni za proces fermentacije. Proces fermentacje je obavljen na temperaturama 16-18<sup>o</sup>C, 18-20<sup>o</sup>C i 20-20<sup>o</sup>C, i sa razliĉitim koncentracijama soli od 1, 1,5 i 2 %. Analizirani su fizički, hemijski, mikrobiolo&scaron;ki parametri i senzorske osobine kupusa tokom fermentacije. Metodom odzivne povr&scaron;ine sa analizom varijanse (ANOVA) modela odziva za svaki od analiziranih karakteristika i obja&scaron;njeno je koji od parametara procesa temperatura, koncentracija soli i vreme trajanja procesa ima statistiĉki značajan uticaj na formiranje matematiĉkih modela odziva, prikazanih u obliku polinoma drugog reda (SOP). Zaključeno je da Futo&scaron;ki kupus postiţe brţe zavr&scaron;nu taĉku fermentacije u odnosu na hibrid Bravo. Drugi kori&scaron;ćeni tehnolo&scaron;ki postupak u ovom radu je osmotska dehidratacija. Kupus je dehidriran u tri osmotska rastvora (vodeni rastvor natrijum hlorida i saharoze, kombinacija vodenog rastvora natrijum hlorida i saharoze i melase i melasa &scaron;ećerne repe) različitih koncentracija, na tri temperature (20&deg;C, 35&deg;C i 50&deg;C) i pri tri vremena trajanja procesa (1, 3 i 5h). Mereni i računati odzivi procesa osmotske dehidratacije bili su: sadržaj suve materije, gubitak vode, prirast suve materije i indeks efiksanosti procesa. Rezultati ispitivanja pokazuju da povećanje tehnolo&scaron;kih parametara temperature i vremena procesa, kao i koncentracije osmotskih rastvora dovode do intenziviranja prenosa mase u procesu i povećanja vrednosti odzivnih parametara procesa. Takođe, zaključeno je da tokom osmotske dehidratacije u melasi &scaron;ećerne repe dolazi do obogaćivanja kupusa nutritivnim komponentama, naročito kalijumom. Treći segment ovog rada je analiza održivosti osmotski dehidriranog kupusa pakovanog u modiifikovanoj atmosferi dve različite sme&scaron;e gasova N<sub>2</sub> i CO<sub>2</sub>. Analizom hemijskih, mikrobiolo&scaron;kih i senzorskih svojstava zaključeno je da ovaj osmotski dehidriran kupus pakovan na navedeni način ima održivost od 90 dana.</p> / <p>This paper describes the process of spontaneous fermentation of traditional product, fermented whole cabbage. In the first part characterization of the local traditional type Futo&scaron;ki cabbage in relation to imported hybrid Bravo was done. Based on the PCA analysis and analysis of the standard score SS physical, chemical and sensory parameters favorable samples for the process of fermentation were selected. The process of fermentation was carried out at three temperatures: 16-18<sup>o</sup>C, 18-20<sup>o</sup>C and 20-20<sup>o</sup>C, and with various concentrations of salt: 1, 1.5 and 2%. The physical, chemical and microbiological parameters, as well as sensory properties of cabbage during fermentation were analyzed. Response surface method with analysis of variance (ANOVA) model response for each of the analyzed characteristics was used and it was explained which of the process parameters (temperature, salt concentration and the duration of the process) had a statistically significant effect on the formation of mathematical models of response, presented in the form of a second order polynomial (SOP). It was concluded that Futo&scaron;ki cabbage faster achieved end point of fermentation as compared to a hybrid Bravo. Another technological method used in this investigation was the osmotic dehydration. Cabbage was dehydrated with three osmotic solutions (an aqueous solution of sodium chloride and sucrose; the combination of an aqueous solution of sodium chloride and sucrose with molasses; sugar beet molasses) of different concentrations, at three temperatures (20&deg;C, 35&deg;C and 50&deg;C) and at three times of the process duration (1, 3, and 5h). The measured and calculated responses of osmotic dehydration process were: dry matter content, water loss, solid gain and the index of efficiency of the process. Test results shown that increase of the technological parameters of temperature and time of process, as well as the concentration of osmotic solutions lead to the intensification of mass transfer in the process and increase values of response parameters of the process. Also, it was concluded that during osmotic dehydration in sugar beet molasses cabbage was enriched with nutritional components, especially potassium. The third segment of this investigation was to analyze the viability of osmotically dehydrated cabbage packaged in modified atmosphere, with two different mixtures of N<sub>2</sub> and CO<sub>2</sub>. Analyzing chemical, microbiological and sensory properties it was concluded that the osmotically dehydrated cabbage packaged in this manner has the sustainability of 90 days.</p>
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Alkoholna fermentacija melase i gustog soka šećerne repe pomoću imobilisanih ćelija Saccharomyces cerevisiae / Alcoholic fermentation of sugar beet molasses and thickjuice by immobilized Saccharomyces cerevisiae cells

Vučurović Vesna 07 September 2012 (has links)
<p>Proizvodnja bioetanola iz među- i nusproizvoda procesa<br />prerade &scaron;ećerne repe, može imati pozitivan uticaj na<br />regionalnu ekomomiju i socio-ekonomski razvoj u zemljama<br />sa razvijenom industrijom konzumnog &scaron;ećera, kao &scaron;to je<br />Srbija. Kao proizvodni mikroorganizam u proizvodnji<br />etanola u najvećoj meri se koristi kvasac Saccharomyces<br />cerevisiae. Primena imobilisanih ćelija kvasca u fermentaciji<br />podloga sa visokom sadržajem &scaron;ećera (iznad 250 g/l), tzv.<br />VHG fermentacija, je često izučavana sa ciljem povećanja<br />efikasnosti proizvodnje etanola. U ovom radu su ćelije S.<br />cerevisiae imobilisane na različitim novim nosačima:<br />presovanim rezancima &scaron;ećerne repe (PR&Scaron;R), suvim<br />rezancima &scaron;ećerne repe (SR&Scaron;R), parenhimskom tkivu stabla<br />kukuruza (PTSK) u obliku diska, na kombinovanim<br />nosačima od PTSK u obliku diska obloženog Ca-alginatom(K1) i ispunjenog Ca-aglinatom (K2), na kuglicama Caalginata(AB) kao i na kombinovanim kuglicama od Caalginata i mliva PTSK (ABC). Imobilisane ćelije kvasca su primenjene za fermentaciju melase i gustog soka &scaron;ećerne repe sa krajnjim ciljem da se racionalnim kori&scaron;ćenjem</p><p>među- i nusproizoda procesa prerade &scaron;ećerne repe postigne<br />efikasna proizvodnja etanola uz smanjene tro&scaron;kove<br />proizvodnje kao, i uz smanjenje emisije otpadnih tokova.<br />U radu je ustanovljeno da su PR&Scaron;R, SR&Scaron;R i PTSK efikasni<br />nosači za imobilizaciju ćelija kvasca zahvaljujući prisustvu<br />pozitivno naelektrisanih funkcionalnih grupa, visokoj<br />poroznosti, hidrofilnosti, mehaničkoj čvrstini i stabilnosti.<br />Takođe ovi nosači &scaron;tite kvasac od osmotskog stresa,<br />toksičnog dejstva etanola i inhibitora. Zahvaljujući<br />heterogenoj strukturi PR&Scaron;R, SR&Scaron;R i PTSK se mogu koristiti<br />kao efikasni adsorbenti za ćelije kvasca, kao i za uklanjanje<br />katjonskih i anjonskih komponenata u postupku prerade<br />otpadnih voda. Pored toga, utvđeno je da PTSK predstavlja<br />alternativni obnovljivi izvor hranljivih materija neophodnih<br />kvascu tokom fermentacije melase i gustog soka, a takođe<br />deluje i kao antipenu&scaron;avac. Primenom ćelija kvasca<br />imobilisanih na SR&Scaron;R ostvarena je maksimalna<br />produktivnost etanola od 1,48 g/lh za melasu i 1,57 g/lh za<br />gusti sok, pri početnoj koncentraciji &scaron;ećera u podlozi 180 g/l.<br />Primenom ćelija kvasca imobilisanih na PTSK u obliku<br />diska (visine oko 5 mm i prečnika oko 20 mm) postignuta je<br />produktivnost etanola 1,26 g/lh za melasu 1,42 g/lh za gusti<br />sok, pri početnoj koncentraciji &scaron;ećera 150 g/l. Osnovni<br />nedostatak primene imobilisanih ćelija na SR&Scaron;R i PTSK u<br />alkoholnoj fermentaciji je lako ispiranje ćelija sa nosača.<br />Kombinovani nosači u obliku diska PTSK obloženog Ca alginatom<br />(K1) i ispunjenog Ca-aglinatom (K2) su<br />pripremljeni kako bi se sprečilo ispiranje ćelija kvasca.<br />Utvrđeno je da nosač K1 nije adekvatan za povećanje<br />efikasnosti imobilizacije. Imobilizacijom kvasca punjenjem<br />nosača K2 je povećana efikasnost imobilizacije ćelija kvasca<br />na PTSK, ali je usled velike zapremine i kompaktnosti<br />nosača K2 tokom fermentacije delimično otežan transport<br />supstrata i produkata kroz disk.<br />Melasa i gusti sok &scaron;ećerne repe su veoma dobre sirovine za<br />proizvodnju etanola, usled visokog sadržaja fermentabilnih<br />&scaron;ećera, koji slobodne i/ili imobiliane ćelije S. cerevisiae mogu<br />direktno koristiti za fermentaciju. Međutim, uzimajući u<br />obzir hemijski sastav ovih sirovina i ostvarene parametre</p><p>fermentacije, utvrđeno je da je gusti sok bolja sirovina za<br />proizvodnju etanola od melase, posebno u VHG uslovima.<br />Takođe je utvrđeno da se gusti sok može koristiti kao<br />sirovina za fermentaciju bez dodataka hranljivih materija.<br />Ustanovljeno je da su melase koje preostaju nakon osmotske<br />dehidratacije crvenog kupusa i mrkve veoma dobre sirovine<br />za proizvodnju etanola pri početnoj koncentraciji &scaron;ećera u<br />podlozi do 150 g/l, ali nisu pogodne sirovine za VHG<br />fermentaciju pomoću slobodnih i imobilisanih ćelija u AB<br />kuglicama. Fermentacijom melase nakon osmotske<br />dehidratacije kupusa i mrkve početne koncentracije &scaron;ećera<br />125 g/l, primenom ćelija kvasca imobilisanih u AB<br />kuglicama, ostvarena je najvi&scaron;a produktivnost etanola od<br />1,24 g/lh i 1,30 g/lh. Tokom fermentacije melase i gustog soka<br />primenom ćelija kvasca imobilisanih u AB kuglicama usled<br />izdvajanja CO2, dolazi do naru&scaron;avanja strukture kuglica<br />pojavom poprečne pukotine koja kuglicu polimera deli na<br />dva približno jednaka dela.<br />Kako bi se sprečila degradacija Ca-alginata tokom<br />fermentacije pripremljen je novi kombinovani nosač od Caalginata<br />i mliva PTSK (ABC). Dodatkom samlevenog PTSK<br />sa mikrostrukturom pčeljinjeg saća u Ca-alginat je povećana<br />poroznost kuglica čime je omogućen efikasniji prenos mase<br />supstrata i produkata, povećana je raspoloživa povr&scaron;ina za<br />adsorpciju i rast ćelija kvasca kao i čvrstina i stabilost<br />kuglica. Poređenjem parametara fermentacije, utvrđeno je<br />da su ćelije kvasca imobilisane na ABC kuglicama efikasniji<br />biokatalizator u poređenju sa slobodnim ćelijama kvasca,<br />kao i u poređenju sa ćelijama imobilisanim u AB kuglicama.<br />Dodatkom samlevenog PTSK u podlogu ili u Ca-alginat<br />povećava se sadržaj etanola i metanola, smanjuje se sadržaj<br />kiselina i acetaldehida u sirovom destilatu, dok se sadržaj<br />vi&scaron;ih alkohola, estara i furfurala ne menja značajno. Ćelije<br />kvasca imobilisane u kombinovanim ABC kuglicama se<br />mogu uspe&scaron;no primeniti za pet ponovljenih fermentacija<br />gustog soka pri standardnim (NG) i uslovima visoke<br />koncentracije &scaron;ećera (VHG) pri čemu se može postići<br />produktivnost etanola 1,92-2,30 g/lh. Primenom imobilisanih<br />ćelija kvasca u kombinovanim ABC kuglicama u<br />kontinualnoj VHG fermentaciji gustog soka, početne<br />koncentracije &scaron;ećera 300 g/l, ostvaren je stabilan<br />fermentacioni sistem tokom 15 dana, pri čemu je<br />produktivnost etanola iznosila 3,29 do 4,66 g/lh.</p> / <p>Bioethanol production from intermediate and byproducts<br />of sugar beet processing has a beneficial scope<br />in view of the socio-economic development and regional<br />economy in countries with developed sugar industry,<br />such as Serbia. Saccharomyces cerevisiae strain is the<br />most widely used ethanol producing microorganism. To<br />increase the efficiency of ethanol production, many<br />process improvements including immobilized cells<br />application and fermentation of very high gravity (VHG)<br />media with initial sugar over 250 g/l, have been studied.<br />In the present work yeast S. cerevisiae was immobilized<br />onto different new carriers: pressed sugar beet pulp<br />(PSBP), dried sugar beet pulp (DSBP), maize stem<br />ground tissue (MSGT) disks, MSGT discs coated with<br />Ca-alginate (K1) and MSGT discs filled with Ca-alginate<br />(K2), Ca-alginate beads (AB) and combined beads made</p><p>of Ca-alginate and maize stem ground tissue meal (ABC).<br />Immobilized yeast cells were used for ethanol<br />fermentation of molasses and thick juice with purposes to<br />obtain efficient ethanol production, to lower high<br />operating costs and to achieve the zero-waste goal<br />through a rational use of by-products of sugar beet<br />processing.<br />In the present work it was found that PSBP, DSBP and<br />MSGT are efficient carriers for yeast cell immobilization<br />due to the presence of positively charged binding sites,<br />high porosity and hidrophylicity, good mechanical<br />strength and stability, while functioned as a fortification<br />against osmotic stress, toxins and inhibitors. It was also<br />found that due to the heterogeneous structure the PSBP,<br />DSBP and MSGT are promising adsorbents for the<br />removal of cationic and anionic compounds from<br />aqueous solutions in the waste water treatment. Besides,<br />it is found that the MSGT can be used as an alternative<br />nutrient source for yeast cells and as an anti foaming<br />agent. A maximum ethanol productivity of 1.48 g/lh and<br />1.57 g/lh was achieved in the fermentation of molasses<br />and thick juice (initial sugar of 180 g/l) using yeast<br />immobilized on DSBP. The highest values of ethanol<br />productivity, obtained in the case of using yeast<br />immobilized on MSGT discs as biocatalyst, for molasses<br />and thick juice (initial sugar of 150 g/l) fermentation<br />were 1.26 g/lh and 1.42 g/lh. The main disadvantage of<br />using DSBP and MSGT supported biocatalyst is intensive<br />leakage of yeast cells during the fermentation. In order to<br />prevent yeast leakage combined carriers in the form of<br />MSGT discs coated with Ca-alginate (K1) and MSGT<br />discs filled with Ca-alginate (K2) were prepared. The K1<br />carrier was found to be unsuccessful for improving yeast<br />immobilization efficiency, while the application K2<br />carrier improved yeast immobilization efficiency during<br />the fermentation. However, due to the large volume and<br />compactness of the K2 carrier substrate and product<br />mass transfer limitation were observed during the<br />fermentation.<br />The sugar beet molasses and thick juice are very good<br />raw materials for ethanol production due to high content<br />of fermentable sugars, which can be directly used for<br />fermentation by free and/or immobilized S. cerevisiae<br />cells without any modification. However, taking into</p><p>consideration quality of these raw materials and obtained<br />fermentation parameters, sugar beet thick juice was<br />found to be more suitable raw material for ethanol<br />fermentation, compared to molasses, particularly in the<br />VHG fermentation process and can be used without any<br />nutrient supplementation. Similarly, it was found that<br />molasses left after the osmotic dehydratation of red<br />cabbage (M1) and carrots (M2) are excellent raw<br />materials for ethanol fermentation of media with initial<br />sugar concentration up to 150 g/l, while they are not<br />convenient for VHG fermentation by free or immobilized<br />yeast cells in AB carrier. Maximum ethanol productivity<br />obtained at the end of fermentation of molasses M1 and<br />M2 by immobilized yeast in AB carrier was 1.24 g/lh and<br />1.30 g/lh, respectively. The release of CO2 during the<br />fermentation of molasses and thick juice by yeast cells<br />immobilized in the AB, lead to breakage of polymer<br />beads on two halves.<br />In order to prevent AB disruption, a new combined yeast<br />carrier (ABC) was developed by the addition of MSGT<br />meal into the Ca-alginate. It was found that the addition<br />of MSGT meal, with honeycomb microstructure,<br />provided large surface area for yeast cell attachment and<br />biofilm growth, and also increased alginate matrix<br />porosity, enabling better mass transfer characteristic,<br />better physical strength and stability of beads. The<br />highest values of fermentation parameters were obtained<br />in the fermentation system with yeast immobilized on<br />ABC carrier in comparison with free yeast cells and yeast<br />immobilized on AB carrier. The Ca-alginate and medium<br />supplementation with MSGT meal significantly increased<br />ethanol and methanol content, decreased acetaldehyde<br />and acetic acid content of the distillate, but did not affect<br />fusel alcohol, ester and furfural content of the distillate.<br />Repeated batch normal gravity (NG) and very high<br />gravity (VHG) ethanol fermentation of thick juice by<br />yeast immobilized on ABC carrier was successfully<br />carried out for at least five successive cycles without any<br />significant decrease in ethanol productivity which was in<br />the range 1.92-2.30 g/lh. Continuous VHG ethanol<br />fermentation of thick juice (initial sugar of 300 g/l) using<br />yeast immobilized on ABC was stable for at least 15 days<br />while achieved ethanol productivity was 3.29-4.66 g/lh.</p>
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Virškinimo procesų karvių didžiajame prieskrandyje ir jų produktyvumo tyrimai, naudojant šėrimui pramonės šalutinius produktus / Investigation of effects of industrial by-products on ruminal digestibility and lactation performance of cows

Šidagis, Darius 10 January 2014 (has links)
Darbo tikslas: Ištirti glicerolio, kvietinių sėlenų su krakmolo gamybos sirupo granulių ir salyklo daigelių efektyvumą melžiamų karvių racionuose bei įvertinti jų įtaką azotinių medžiagų fermentacijai karvių didžiajame prieskrandyje. Darbo uždaviniai: 1. Ištirti krakmolo gamybos sirupo, kvietinių sėlenų ir krakmolo gamybos sirupo granulių, salyklo daigelių cheminę sudėtį ir apskaičiuoti energetinę vertę. 2. Atlikti penkis šėrimo bandymus su melžiamomis karvėmis: tris bandymus panaudojant glicerolį skirtingais laktacijos periodais, vieną – naudojant krakmolo dekstrinų sirupą ir vieną – naudojant salyklo daigelius. 3. Nustatyti karvių racionų pašarų ėdamumą. 4. Atlikti karvių didžiojo prieskrandžio (Rumen) turinio tyrimus, jame nustatyti: sausąsias medžiagas, infuzorijų skaičių, pH, lakių riebalų rūgščių (LRR) suminį kiekį ir procentinį santykį, bendro ir amoniako azoto kiekius. 5. Įvertinti tiriamų pašarų įtaką pieno primilžiui, nustatyti pieno riebalų ir baltymų kiekius ir įvertinti ekonominį efektyvumą. 6. Tyrimų duomenis apdoroti statistiškai pateikiant aritmetinius vidurkius ir aritmetinio vidurkio paklaidą. Mūsų tyrimuose pirmą kartą Lietuvoje glicerolis panaudotas kaip pašaras melžiamų karvių racionuose skirtingais laktacijos periodais drėgnuose pašarų mišiniuose, sėlenų granulės, praturtintos krakmolo dekstrinų sirupu ir salyklo daigeliai nustatant jų poveikį azotinių medžiagų ir angliavandenių fermentacijai karvių didžiajame prieskrandyje, jų produktyvumui bei... [toliau žr. visą tekstą] / The purpose of the study: To investigate the efficiency of glycerol, wheat bran with starch dextrin syrup pellets and malt shoots in the diets of lactating cows and the effects of these products on nitrogen matter fermentation in the rumen of cows. Objectives: 1. To analyze the chemical composition and calculate the energy value of starch syrup, wheat bran and starch syrup pellets and malt shoots. 2. To carry out 5 feeding trials with lactating cows, i. e. 3 trials using glycerol at different lactation periods, one – using starch dextrin syrup and one – using malt shoots. 3. To determine the intake of feeds in the diets. 4. To study rumen contents for the analysis of dry matter, infusoria count, pH-value, total volatile fatty acids (VFA) and percentage ratio, contents of total and ammonia nitrogen. 5. To assess the influence of the above feedstuffs on milk yields, milk fat and protein contents and economic efficiency. 6. To statistically process the data and give arithmetic means and mean deviations. In this study for the first time in Lithuania, glycerol was used as a feedstuff in the diets of lactating cows at different lactation periods in wet mash, bran pellets enriched with starch dextrin syrup and malt shoots for determination of their effect on nitrogen matter and carbohydrate fermentation in the rumen of cows, cow productivity and economic efficiency. Practical application: After completion of the study, recommendations for milk producers were prepared on the usage of... [to full text]

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