Viscosity and fermentability are considered important properties of dietary fiber. Viscosity increases digesta viscosity and reduces digesta passage rate, nutrient digestion and absorption whereas fermentability increases fermentation into short chain fatty acids (SCFA). The objectives were to enhance the understanding of these properties of dietary fiber and their effects on digestive physiology using surgical models in pigs. In study 1, three catheterized pigs fed 3 diets containing 0, 3, or 6% oat -glucan concentrate (BG0, BG3, and BG6) in a repeated 3 3 Latin square. Pigs fed BG6 had a lower net glucose flux. Pigs fed BG6 tended to have lower portal C-peptide without lowered insulin. Pigs fed BG6 had lower portal glucose dependent insulinotropic peptide (GIP) and glucagon like peptide-1 (GLP-1), which in turn were correlated (R2 = 0.81 and 0.88, respectively) with portal glucose. Pigs fed BG3 and BG6 had a higher net SCFA flux, indicating increased fermentation. In study 2 and 3, ileal cannulated grower pigs were fed semi-purified diets supplemented with 5% purified non-starch polysaccharides (NSP) in a 2 (low and high viscous) 2 (low, and high fermentable) factorial arrangement using cellulose (CEL), carboxymethylcellulose (CMC), and low and high viscous oat -glucan (LBG and HBG, respectively). The CMC, LBG and HBG induced high ileal digesta viscosity coinciding with high nutrient digestibility; in contrast, CEL had lowest viscosity and nutrient digestibility. The CEL, LBG and HBG increased fecal SCFA. Linear discriminate analysis of NSP and TRFLP profiles and 16S rRNA gene copy numbers of bacterial groups revealed that CMC resulted in distinctive bacterial communities. The gene copy number of butyryl-CoA CoA transferase was higher than for butyrate kinase, indicating that this pathway is dominant for butyrate production in pigs. In study 4, similar dietary treatments were fed to catheterized pigs. High viscous and fermentable HBG increased net butyrate flux and insulin and GLP-1 production but did not affect net glucose flux. Thus, the viscosity and fermentability are important functional properties of dietary fiber that better explained the physiological effects on kinetics of digestion, absorption, hormones responses, fermentation and thus nutrient flow and intestinal health. / Animal Science

No description available.

The basic aim of barley malt breeders and maltsters is to produce malt with optimum fermentability levels. The purpose of this research was to understand and evaluate the effect of wort boiling and autoclaving at varying time periods (30, 45, 60, 90, and 120 min) on malt fermentability. The effect of trub content was also analyzed. Small-scale fermentations were carried out using a ‘Control malt’ and a standard SMA yeast strain. The Apparent Degree of Fermentability (ADF), Turbidity (absorbance at 600nm), and Density (oPlato) were measured at specific time intervals over three day fermentation period and non-linearly modeled. From the results obtained, we suggest that heat treating wort with or without trub, (at 100°C, 121.1°C) for a range of times results in significant decline in the ADF (p<0.05). Free amino nitrogen levels of wort declined significantly with respect to both increase in wort boiling temperature and intervals (p<0.001).

The primary goal of this study was to investigate and compare the fermentation performance of malt produced from eleven Canadian two-row barley varieties grown during the 2007 and 2008 crop seasons. Common malting varieties tested included Harrington, AC Metcalfe, CDC Copeland, CDC Kendall, and feed varieties CDC Dolly, CDC Bold, CDC Helgason and McLeod. As well, three experimental varieties, TR251; TR306; and BM9752D-17, were included in this study due to their varied display of enzymatic activity; of chief interest was the ?-amylase thermal stability. Fermentations were carried out using the standard miniaturized fermentation assay and SMA yeast. Apparent Extract (AE), absorbance, fermentable carbohydrates, and ethanol were measured throughout fermentation. Attenuation, carbohydrate and ethanol data were modeled using the logistic equation, and absorbance data was modeled using the newly developed Tilted Gaussian equation. Results indicate that all but the feed varieties fermented well, achieving low final attenuation, and exhibiting similar fermentation characteristics. Despite only minor performance differences among the top fermenters, it was found that between crop seasons both AC Metcalfe and CDC Copeland fermented as well or better than Harrington, as measured by their respective Apparent Degree of Fermentation (ADF). Harrington displayed substantial performance variation between seasons, while test variety BM9752D-17 fermented the most consistently between years, displaying enhanced fermentation to that of Harrington in 2008. Despite high ?-amylase thermostability, BM9752D-17 did not display enhanced fermentation performance to that of CDC Copeland or AC Metcalfe.

The quantity of alcohol produced through wort fermentation is fundamental to a malt’s quality. Good fermentability is dependent on many malt quality parameters but requirement for proteases to provide amino acids and peptides for yeast is poorly understood. The thesis investigated relationships between amino acid profiles, endoprotease activities and fermentability under different malting and brewing conditions. Methods for measuring individual wort amino acids, endoprotease activity and fermentability were modified or developed to better understand the relationships. Levels of lysine and glycine were affected the most by malting and the variability was not always well predicted by the standard FAN analysis. Cysteine endoprotease activity developed similarly to total amino acids levels but associations were not significant Amino acids were limiting to fermentability at low yeast pitching rates and with the use of high maltose syrups but malt modification was the key determinant of fermentability. Studies on non fermentable sugar content were recommended.

The quantity of alcohol produced through wort fermentation is fundamental to a malt’s quality. Good fermentability is dependent on many malt quality parameters but requirement for proteases to provide amino acids and peptides for yeast is poorly understood. The thesis investigated relationships between amino acid profiles, endoprotease activities and fermentability under different malting and brewing conditions. Methods for measuring individual wort amino acids, endoprotease activity and fermentability were modified or developed to better understand the relationships. Levels of lysine and glycine were affected the most by malting and the variability was not always well predicted by the standard FAN analysis. Cysteine endoprotease activity developed similarly to total amino acids levels but associations were not significant Amino acids were limiting to fermentability at low yeast pitching rates and with the use of high maltose syrups but malt modification was the key determinant of fermentability. Studies on non fermentable sugar content were recommended.

A glicerina, na alimentação, pode ser considerada uma boa fonte energética. Assim, sua utilização como substituta em parte de grãos e outros alimentos ricos em amido é amplamente estuda já que esses alimentos podem causar alterações metabólicas e digestivas quando em alto consumo. Neste estudo, objetivou-se comparar níveis de adição de glicerina na dieta de equinos. Foram utilizados oito pôneis machos, castrados, da raça Mini-Horse, com idade aproximada de 9 anos ± 6 meses, peso corporal médio de 149,80 &#177; 17,20 kg e escore corporal médio de 5,4 &#177; 0,7. Os animais foram alojados em baias individuais. Adotou-se consumo diário individual de 1,75% do peso corporal (PC), sendo 1% do PC em matéria seca (MS) proveniente do volumoso e 0,75% do PC em MS do concentrado, com proporção 60:40 (volumoso:concentrado). O delineamento experimental utilizado foi o quadrado latino duplo 4 x 4 contemporâneos. As dietas diferiram quanto ao nível de inclusão de glicerina (0, 4, 8 e 12%) que foram calculados com relação á porcentagem de concentrado fornecidos por animal. As avaliações foram realizada em quatro períodos, sendo 14 dias de adaptação à dieta, 5 dias de coleta total de fezes (CTF) e 2 semanas de intervalo entre os períodos. Avaliou-se a digestibilidade aparente total dos nutrientes e fermentabilidade da glicerina a partir da CTF, por meio das análises de respostas glicêmicas, insulinêmicas, ácido graxos da cadeia curta, ácidos graxos não esterificados (NEFA) e pH das fezes. Também foram realizadas análises de segurança e aceitabilidade que se constituiu de análises de função hepática e renal, triglicerídeos, colesterol e frações além da avaliação do comportamento alimentar dos animais. Além de análise de implicações econômica a partir da simulação de substituição do milho pela glicerina bruta. Os dados foram submetidos à análise pelo programa Statistical Analysis System (SAS Institute Inc., 2010). Para os resultados significativos, foi utilizado o teste de Tukey com P&lt;0,05. Não houve diferenças entre os tratamentos em nenhuma das análises realizadas (P&lt;0,05). A glicerina se mostrou palatável e com aceitabilidade. A substituição de milho por glicerina, mesmo em valores de 1%, representa economicamente 0,42% de ganho. A suplementação de glicerina bruta na dieta de equinos se apresenta como segura não afetando o comportamento alimentar, a higidez e a saúde digestiva dos animais, possuindo justificativa econômica para uso. / Glycerin in food can be considered a good source of energy. Thus, its use as a substitute part of grains and other starchy foods is widely studied since these foods can cause metabolic and digestive changes when in high consumption. The objective of this study was to compare levels of glycerin addition in the equine diet. Eight male, castrated Mini-Horse male ponies, aged approximately 9 years ± 6 months, mean body weight of 149.80 &#177; 17.20 kg and mean body score of 5.4 &#177; 0.7 were used. The animals were housed in individual stalls. Individual daily consumption of 1.75% of body weight (CP) was used, with 1% CP in dry matter (DM) from bulky and 0.75% CP in DM from concentrate, with a ratio of 60:40 voluminous: concentrate). The experimental design used was the contemporary 4 x 4 double Latin square. The diets differed in the glycerin inclusion levels (0, 4, 8 and 12%) that were calculated in relation to the percentage of concentrate supplied per animal. The evaluations were performed in four periods, 14 days of adaptation to the diet, 5 days of total collection of feces (TCF) and 2 weeks of interval between periods. The total apparent digestibility of nutrients and fermentability of glycerol from the TCF were evaluated through glycemic, insulinemic, short chain fatty acid, non-esterified fatty acid (NEFA) and faecal pH analyzes. Safety and acceptability analyzes were also performed, which consisted of analyzes of liver and renal function, triglycerides, cholesterol and fractions, besides the evaluation of the animals\' feeding behavior. In addition to analysis of economic implications from the simulation of substitution of corn by crude glycerin. The data were submitted to analysis by the Statistical Analysis System (SAS Institute Inc., 2010). For the significant results, the Tukey test was used with P &lt;0.05. There were no differences between treatments in any of the analyzes performed (P &lt;0.05). Glycerin was palatable and acceptable. The substitution of corn for glycerin, even at 1%, represents economically 0.42% gain. The supplementation of crude glycerin in the equine diet presents itself as safe, without affecting the alimentary behavior, the hygiene and the digestive health of the animals, with economic justification for use.

A glicerina, na alimentação, pode ser considerada uma boa fonte energética. Assim, sua utilização como substituta em parte de grãos e outros alimentos ricos em amido é amplamente estuda já que esses alimentos podem causar alterações metabólicas e digestivas quando em alto consumo. Neste estudo, objetivou-se comparar níveis de adição de glicerina na dieta de equinos. Foram utilizados oito pôneis machos, castrados, da raça Mini-Horse, com idade aproximada de 9 anos ± 6 meses, peso corporal médio de 149,80 &#177; 17,20 kg e escore corporal médio de 5,4 &#177; 0,7. Os animais foram alojados em baias individuais. Adotou-se consumo diário individual de 1,75% do peso corporal (PC), sendo 1% do PC em matéria seca (MS) proveniente do volumoso e 0,75% do PC em MS do concentrado, com proporção 60:40 (volumoso:concentrado). O delineamento experimental utilizado foi o quadrado latino duplo 4 x 4 contemporâneos. As dietas diferiram quanto ao nível de inclusão de glicerina (0, 4, 8 e 12%) que foram calculados com relação á porcentagem de concentrado fornecidos por animal. As avaliações foram realizada em quatro períodos, sendo 14 dias de adaptação à dieta, 5 dias de coleta total de fezes (CTF) e 2 semanas de intervalo entre os períodos. Avaliou-se a digestibilidade aparente total dos nutrientes e fermentabilidade da glicerina a partir da CTF, por meio das análises de respostas glicêmicas, insulinêmicas, ácido graxos da cadeia curta, ácidos graxos não esterificados (NEFA) e pH das fezes. Também foram realizadas análises de segurança e aceitabilidade que se constituiu de análises de função hepática e renal, triglicerídeos, colesterol e frações além da avaliação do comportamento alimentar dos animais. Além de análise de implicações econômica a partir da simulação de substituição do milho pela glicerina bruta. Os dados foram submetidos à análise pelo programa Statistical Analysis System (SAS Institute Inc., 2010). Para os resultados significativos, foi utilizado o teste de Tukey com P&lt;0,05. Não houve diferenças entre os tratamentos em nenhuma das análises realizadas (P&lt;0,05). A glicerina se mostrou palatável e com aceitabilidade. A substituição de milho por glicerina, mesmo em valores de 1%, representa economicamente 0,42% de ganho. A suplementação de glicerina bruta na dieta de equinos se apresenta como segura não afetando o comportamento alimentar, a higidez e a saúde digestiva dos animais, possuindo justificativa econômica para uso. / Glycerin in food can be considered a good source of energy. Thus, its use as a substitute part of grains and other starchy foods is widely studied since these foods can cause metabolic and digestive changes when in high consumption. The objective of this study was to compare levels of glycerin addition in the equine diet. Eight male, castrated Mini-Horse male ponies, aged approximately 9 years ± 6 months, mean body weight of 149.80 &#177; 17.20 kg and mean body score of 5.4 &#177; 0.7 were used. The animals were housed in individual stalls. Individual daily consumption of 1.75% of body weight (CP) was used, with 1% CP in dry matter (DM) from bulky and 0.75% CP in DM from concentrate, with a ratio of 60:40 voluminous: concentrate). The experimental design used was the contemporary 4 x 4 double Latin square. The diets differed in the glycerin inclusion levels (0, 4, 8 and 12%) that were calculated in relation to the percentage of concentrate supplied per animal. The evaluations were performed in four periods, 14 days of adaptation to the diet, 5 days of total collection of feces (TCF) and 2 weeks of interval between periods. The total apparent digestibility of nutrients and fermentability of glycerol from the TCF were evaluated through glycemic, insulinemic, short chain fatty acid, non-esterified fatty acid (NEFA) and faecal pH analyzes. Safety and acceptability analyzes were also performed, which consisted of analyzes of liver and renal function, triglycerides, cholesterol and fractions, besides the evaluation of the animals\' feeding behavior. In addition to analysis of economic implications from the simulation of substitution of corn by crude glycerin. The data were submitted to analysis by the Statistical Analysis System (SAS Institute Inc., 2010). For the significant results, the Tukey test was used with P &lt;0.05. There were no differences between treatments in any of the analyzes performed (P &lt;0.05). Glycerin was palatable and acceptable. The substitution of corn for glycerin, even at 1%, represents economically 0.42% gain. The supplementation of crude glycerin in the equine diet presents itself as safe, without affecting the alimentary behavior, the hygiene and the digestive health of the animals, with economic justification for use.

Thesis (MSc Food Sc)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The relationship between malt fermentability and rheological variables, measured by means of the Rapid Visco Analyser (RVA) and application of multivariate data analysis, was investigated. The RVA Kilned Malt method was optimised to achieve maximum rheological discrimination between malt samples, differing in fermentability. Five concentrations and two particle sizes were used to investigate each malt sample. Data were analysed by two different data analysis techniques, namely principal component analysis (PCA) and analysis of variance (ANOVA). Rheological variables for peak-height, -width, -area and time occurrence, were able to discriminate between high (Metcalfe, Flagship), intermediate (SSG 585, PUMA) and low malt fermentability (SSG 506, SSG 564). Variation in particle size showed insignificant (P>0.05) fermentability discrimination. The malt to water ratio of 1:1.5 provided the best discrimination in fermentability. PCA applied to the entire dataset was the superior data analysis technique. Partial least squares (PLS) regression and Soft Independent Modeling of Class Analogy (SIMCA) were applied to predict malt fermentability. Recorded RVA data was regressed with both apparent attenuation limit (AAL) and free amino nitrogen (FAN), independently. Developed PLS calibration models were validated by test set and segmented crossvalidation for AAL and FAN, respectively. The SIMCA classification model developed was based on different malt fermentability classes, each PCA validated independently by test set validation. A strong correlation between RVA analysis and AAL was obtained (r=0.92), while FAN delivered a weak correlation (r=0.59). Regarding the SIMCA model; the proportion of test set samples correctly classified in terms of malt fermentability was 83%. South African malt blends were predicted to have low malt fermentability. Simulated blends were predicted to have high fermentability when using a minimum of 80% Metcalfe blended with SSG 506. Blends containing higher percentages of the low malt fermentability cultivar (SSG 506) were predicted to have an overall intermediate fermentability. Different experimental conditions were investigated during RVA analysis (i.e. instrument model; time/temperature profile, enzyme activity and heating/cooling rate). Rheological measurement using different RVA models gave similar PCA results, indicating adequate sensitivity of the older instrument for discrimination purposes. Matching the time/temperature profile used in the commercial brewery mashing process was rejected due to increased analysis time and rheological noise while reducing fermentability discrimination. Inactivating malt enzymes prior to RVA analysis provided useful sample information, such as the large starch granule’s mean diameter, extract and starch content, by measuring peak height and iv time to peak. The amount of starch damage inflicted on a malt sample increased after repeated centrifugal milling, but was unaffected by the sieve size used. Multivariate data analysis is a suitable statistical technique applied to rheological data and provided more relevant information than traditional univariate techniques. The RVA can be considered an ideal instrument within a grain laboratory as it allowed the investigation of different operating conditions. It is beneficial to use an inexpensive, routine method of analysis to measure various interacting factors. RVA rheological measurement demonstrated to be a decisive monitor of malt fermentability and is highly recommended to be incorporated within the barley breeding, malting and brewing industries. / AFRIKAANSE OPSOMMING: Die verwantskap tussen mout fermenteerbaarheid en reologie-veranderlikes, gemeet met die “Rapid Visco Analyser” (RVA) en toepassing van meerveranderlike data analise is ondersoek. Die RVA “Kilned Malt” metode is geoptimeer om maksimum reologiese diskriminasie, tussen gars kultivars van verskillende fermenteerbaarheid, te lewer. Vyf konsentrasies en twee partikel groottes is gebruik in die ondersoek vir elke mout monster. Data is deur beide hoof komponent analise (HKA) en variansie-analise (ANOVA) ondersoek om die verskillende data analise metodes met mekaar te vergelyk. Reologiese veranderlikes vir piek-hoogte, - wydte, -area en -vormingstyd, kon diskrimineer tussen hoë (Metcalfe, Flagship), intermediêre (SSG 585, PUMA) en lae (SSG 506, SSG 564) mout fermenteerbaarheid. Variasie in partikel grootte kon nie beduidende diskriminasie in fermenteerbaarheid aantoon nie. Die mout-totwater konsentrasie van 1:1.5 het die beste diskriminasie in fermenteerbaarheid gelewer. Die toepassing van HKA op die hele datastel was die beter analitiese tegniek. Parsiële kleinste kwadrate (PKK) regressie en Sagte Onafhanklike Modellering van Klas Analogie (SIMCA) is toegepas om mout fermenteerbaarheid te voorspel. Regressie tussen RVA data en skynbare attenuasie limiet (AAL), sowel as vrye amino stikstof (FAN) inhoud, is afsonderlik uitgevoer. Die geldigheid van regressie modelle is deur middel van toets stel en gesegmenteerde kruis-validasie vir AAL en FAN onderskeidelik uitgevoer. SIMCA klassifikasie modelle is gebaseer op verskillende mout fermenteerbaarheids-klasse, waarvan elke HKA klas individueel geldig is. RVA analise het ‘n sterk korrelasie met AAL (r=0.92), maar ‘n swak korrelasie met FAN (r=0.59) getoon. Die SIMCA model het 83% van toets stel monsters as korrek geklassifiseer in terme van mout fermenteerbaarheid. Suid Afrikaanse mout mengsels is voorspel as swak fermenteerbaar. Nagebootste mengsels is voorspel as hoogs fermenteerbaar wanneer minimum 80% Metcalfe met SSG 506 vermeng word. Sodra ‘n hoër persentasie van die swakker fermenteerbaarheids-kultivar (SSG 506) bygevoeg is, word intermediêre fermenteerbaarheid voorspel. Tydens RVA analise is verskillende eksperimentele toestande ondersoek (byvoorbeeld instrument model; tyd/temperatuur profiel; ensiem aktiwiteit en verhittings/verkoelings tempo). Die gebruik van verskillende RVA modelle het soortgelyke HKA resultate gelewer. Dus bevat die ouer instrument aanvaarbare sensitiwiteit vir diskriminasie doeleindes. Nabootsing van die tyd/temperatuur profiel in die kommersiële brouproses is verwerp, aangesien analise tyd en reologiese geraas toegeneem het, terwyl fermenteerbaarheidsdiskriminasie verminder het. Inaktivering van mout ensieme voor RVA analise lewer nuttige monster inligting; deur veranderlikes soos piek-hoogte en piek-tyd te meet, kan die groot stysel korrel se gemiddelde deursnit, ekstrakwaarde en stysel inhoud verkry word. Herhaalde sentrifugale maling van ‘n mout monster lei tot beskadiging van stysel, maar dit word nie deur sif grootte beïnvloed nie. Die toepassing van meerveranderlike data analise op reologiese data is waardevol en lewer meer relevante inligting in vergelyking met tradisionele eenveranderlike data analise. Die RVA is ‘n ideale instrument vir gebruik in ‘n graan laboratorium aangesien dit verskillende operatiewe kondisies kan ondersoek. Die gebruik van ‘n enkele, goedkoop, roetine analitiese metode is voordelig en het die potensiaal om ‘n magdom interaktiewe faktore te meet. RVA reologiese meting demonstreer die vermoë as ‘n deurslaggewende tegniek vir die bepaling van mout fermenteerbaarheid, gevolglik word toepassing sterk aanbeveel binne die gars teëlings-, vermoutings- en brouers-industrieë.

Orientador: Pilar Rodriguez de Massaguer / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-16T13:46:22Z (GMT). No. of bitstreams: 1 NolascoJunior_Jonas_D.pdf: 1793020 bytes, checksum: 50a108545c351293fc67eba7a94f669d (MD5) Previous issue date: 2010 / Resumo: Nesta pesquisa foi verificada a eficiência de tratamento térmico UHT para mostos a base de caldo de cana e melaço, otimizado para preservação máxima (> 98,7%) do conteúdo dos açúcares sacarose, glicose e frutose causando 3 reduções logarítmicas no micro-organismo alvo, os esporos de Geobacillus stearothermophilus ATCC 1518. Os mostos tratados termicamente tiveram suas características fermentativas avaliadas utilizando as linhagens industriais de leveduras LNF SA-1 e LNF BG-1, utilizadas na produção de bioetanol. A eficiência dos processos térmicos otimizados foi avaliada em unidade piloto de esterilização contínua Microthermics® com aquecimento indireto utilizando os binômios 125ºC/30s, 130ºC/11s, 130ºC/37s e 135ºC/5s, selecionados a partir de estudos cinéticos de destruição térmica dos esporos de G. stearothermophilus ATCC 1518 nas temperaturas 98º, 110ºC, 120ºC, 122,5ºC e 130ºC e dos açúcares sacarose, glicose, frutose e açúcares redutores totais, ART, nas temperaturas 110ºC, 120ºC, 130ºC e 140ºC, utilizando como meio mosto a 21,5ºBrix e pH 6. Os estudos cinéticos foram realizados em batelada com tubos TDT, 6 mm DI x 8 mm DE x 100 mm de comprimento. O protocolo de processo representado pelo binômio 135ºC/5s foi obtido por extrapolação. O processo térmico contínuo se mostrou mais eficiente que o processo predito através dos ensaios cinéticos em batelada. O número de reduções logarítmicas médio de 2,58 obtido experimentalmente, (nintegral-biológico), em cada um dos protocolos de processo utilizado, foi 7,35% maior que os valores calculados de 2,41, (nintegral-calculado), utilizando os perfis de temperatura obtidos em cada uma das secções da unidade piloto de esterilização, estimados com a velocidade média de escoamento. A preservação da sacarose foi maior que 99,20% enquanto que a preservação dos açúcares redutores totais foi superior a 99,52%. Nos dois processos térmicos com os binômios 130ºC/37s os valores de nintegral-biológico foram maiores que 5,87 e 7,47 e preservação dos açúcares mínima de 99.45%. Teoricamente qualquer dos protocolos de processos térmicos é capaz de causar 108 reduções logarítmicas nos Lactobacillus sp, contaminante comumente encontrados nos mostos durante fermentação. Com relação às características fermentativas dos mostos tratados termicamente, as velocidades específicas máximas de crescimento diminuíram com o aumento da temperatura de tratamento térmico dos mostos de 0,42 h-1 para 0,19 h-1 para LNF SA-1 e de 0,57 h-1 para 0,09 h-1 para LNF BG-1. Os tempos de adaptação obtidos para a linhagem LNF SA-1 variaram de 3,10 h a 4,97 h, mas, em mostos tratados na temperatura mais elevada de 135ºC por 5s, foi de 11,17 h. Para a linhagem LNF BG-1 os tempos de adaptação obtidos variaram de 5,92 h para 6,65 h para os binômios 125ºC/30s, 130ºC/11s e 130ºC/37s, mas no tratamento com o binômio 135ºC/5s foi obtido 10,88 h. A produtividade das leveduras ficou entre 0,24-0,34 g etanol/g de célula/h enquanto que o rendimento em etanol variou de 87,56% a 89,73%, valores dentro dos padrões industriais. Máximo rendimento foi obtido quando foi utilizado mosto tratado a 130ºC/37s em que foi obtido valor de nintegral-biológico maior que 5,87, indicando que os protocolos de tratamento térmicos podem ter exercido diferentes efeitos sobre a disponibilidade de macro e micro nutrientes essenciais para as leveduras / Abstract: In this research is verified the efficiency of a UHT heat treatment process for musts based on sugar cane juice and molasses optimized for maximum preservation of the content in the sugars sucrose, glucose and fructose, using as target the heat resistant spores of Geobacillus stearothermophilus ATCC 1518. Heat treated musts had their fermentative characteristics evaluated using the industrial yeast strains LNF SA-1 and LNF BG-1 for the production of bioethanol in Brazil. The efficiency of the thermal graphically optimized processes was assessed in continuous sterilization Microthermics® pilot plant with indirect heating following the binomials 125ºC/30s, 130ºC/11s, 130ºC/37s and 135ºC/5s, selected from thermal destruction kinetic studies of G. stearothermophilus spores at the temperatures 98ºC, 110ºC, 120ºC, 122.5ºC, 125ºC and 130ºC, and of the sugars sucrose, glucose, fructose and total reducing sugars, TRS, at the temperatures 110ºC, 120ºC, 130ºC and 140ºC, in must media, 21.5ºBrix and pH 6.4. Kinetic studies were carried out in batch, using TDT tubes 6 mm DI x 8 mm DE x 100 mm length. The process condition of the binomial 135ºC/5s was obtained by extrapolation. The continuous heat process was more efficient than the predicted from the batch kinetic tests. The mean number, 2.58, of integral log reduction experimentally obtained for the target microorganism, (nintegral-biological), was 7.35% higher than the mean number, 2.41, of integral calculated values, (nintegral-calculated), using the temperature profile estimated for each of section of the pilot unit with the mean flow velocity. It was found that sugar retention in the musts thermally processed was higher than 99.2% and 99.52% for sucrose and total reducing sugar, respectively. The two thermal processes that followed the binomial 130ºC/37s resulted in nintegral-biological greater than 5.87 and 7.47 with minimal preservation of sugars of 99.45%. Theoretically any of these processes is capable of causing 108 decimal reductions on Lactobacillus sp, typical contaminant found in musts and fermentation. Fermentation characteristics of heat-treated musts were assessed and the kinetic responses of the yeasts in terms of their maximum specific growth rates, in the heat treated musts, decreased with increase in heat treatment temperature of the musts from 0.42 h-1 to 0.19 h-1 for LNF SA-1 and from 0.57 h-1 to 0.09 h-1 for LNF BG-1. The adaptation times obtained for strain LNF SA-1 varied from 3.10 h to 4.97 h, but in musts treated with the highest temperature, 135ºC for 5s, the value was 11.17 h. For the strain LNF BG-1 the adaptation times varied from 5.92 h to 6.65 h, but in musts treated with the highest temperature, 135ºC for 5s, the value was 10.88 h. Cell productivity was in the range of 0.24-0.34 g ethanol/g of cell/h and the yield was in the range 87.56 - 89.73%. Maximum fermentation yield was obtained using musts treated with the binomial 130ºC/37s, for which integral biological n-values found was greater than 5.87, suggesting that the thermal treatment protocols may have exerted different effects on availability of macro and micro essential nutrients for yeasts / Doutorado / Doutor em Ciência de Alimentos