Based on previous testing and analysis, it is believed that North American concrete design codes yield conservative shear designs for precast/prestressed hollow-core slabs in the 203 to 305 mm depth range. The objective of this research program is to calibrate the Canadian code shear equations to precast/prestressed hollow-core slabs, through testing a series of full-scale slabs to failure in shear. A total of twelve hollow-core slabs from one slab producer, using two types of extruders were tested in shear. Test variables include the bearing length and the prestressing level. Results are presented in terms of experimental to predicted capacity using the Canadian and American concrete design codes, the failure mode, crack profiles, and the critical section location for shear. It was concluded that the Canadian code shear equations are inappropriate for use with hollow-core slabs with low prestressing levels in the 203 to 305 mm depth range.

Based on previous testing and analysis, it is believed that North American concrete design codes yield conservative shear designs for precast/prestressed hollow-core slabs in the 203 to 305 mm depth range. The objective of this research program is to calibrate the Canadian code shear equations to precast/prestressed hollow-core slabs, through testing a series of full-scale slabs to failure in shear. A total of twelve hollow-core slabs from one slab producer, using two types of extruders were tested in shear. Test variables include the bearing length and the prestressing level. Results are presented in terms of experimental to predicted capacity using the Canadian and American concrete design codes, the failure mode, crack profiles, and the critical section location for shear. It was concluded that the Canadian code shear equations are inappropriate for use with hollow-core slabs with low prestressing levels in the 203 to 305 mm depth range.

Master of Science / Food Science Institute, Human Ecology / Koushik Adhikari / The potential health benefits of spices, used as flavor enhancers since ancient times, are being explored more and more by researchers in animal and in vitro models. The application of mood and emotion constructs to understand the consumer psyche is a relatively new area of study in food science. The main objective of our study was to determine if spices (a blend of cinnamon, ginger, nutmeg, and cloves) that have high antioxidant properties evoke/change emotions in consumers. The carrier food, an extruded apple-based cereal-like product, was selected because cereals are convenient and consumed by many. Three cereal-like products containing 0, 4, or a 5% spice blend were extruded at Kansas State University. Four consumer tests, one day of hedonic and just-about-right evaluations (n= 100), followed by three days of emotion testing were carried out. For the emotion tests, 25 consumers saw the control sample three times, 25 consumers saw the 4% blend sample three times, 25 consumers saw the 5% blend sample three times, and 25 consumers saw all three samples once. In a clinical trial (n=10), total antioxidant capacity and blood glucose levels were determined from two samples (control and the 4% blend). The data were subjected to analysis of variance and principal components analysis to determine significant effects and trends in the data, respectively. ‘Calm’ was the only emotion that was significantly different in all three samples, which decreased over time (pre-consumption to 1-hour post consumption). The emotion ‘Satisfied’ increased significantly in the 5% blend showing that there might have been an effect because of the higher spice content. The PCAs showed that for the 4% and 5% blends, the movement of the consumers was towards emotions such as active, energetic, and enthusiastic. There were no trends for the control. For the clinical trial, the 4% blend was significantly higher (P < 0.05) in total antioxidant capacity than the baseline, although the differences in absolute terms are debatable. Blood glucose levels were not significantly different. Future research needs to be done to better understand how individual emotions affect overall liking and product acceptance.

The influence of plasticization and other formulation factors on the properties of hot-melt extruded dosage forms for the controlled release of water-soluble active compounds was investigated. Citric acid monohydrate was demonstrated to function as a solid-state plasticizer in hot-melt extruded Eudragit® RS PO tablets and in cast films when concentrations below the compatibility limit were employed. Melting of the organic acid and solubilization in the polymer during extrusion were necessary to observe the plasticizing effect. The release rate of diltiazem hydrochloride, used as a high-melting, water-soluble model drug, from melt extruded Eudragit® RS PO matrix tablets increased and became independent of the original drug particle size in the presence of citric acid monohydrate. Thermal analysis of physical mixtures demonstrated that citric acid promoted drug melting during extrusion by interaction and melting point depression. Diltiazem hydrochloride remained amorphous in the final dosage form, and leaching of citric acid monohydrate enhanced drug diffusion by increasing the matrix porosity. Delayed-release matrix pellets with particle sizes below one mm were prepared by hot-melt extrusion, and the influence of the matrix forming polymer and the type and level of plasticizer on the processibility and release properties was investigated. Pellets complied with the USP requirement for delayed release articles to release less than 10% drug at pH 1.2 after 2 hours when plasticized Eudragit® S100 was used as the release-controlling material. High levels of efficient plasticizers had to be employed to decrease the polymeric melt viscosity, increase the process yield and enable extrusion at moderate temperatures to avoid instabilities during processing and storage. The aqueous solubility of the plasticizer further impacted the drug release rate in acid. A novel application of hot-melt extrusion for the preparation of monolithic matrices comprising enteric coated particles was studied. The influence of the mechanical strength of the multiparticulates, pellet loading and nature of the hydrophilic carrier material on the preservation of the delayed-release properties after extrusion was investigated. Soft particles coated with brittle films remained intact when low-melting carriers that did not solubilize the enteric film during extrusion were used, and the dissolution profile was stable over one year. / text

This thesis reports a fundamental study on microwave assisted moulding (MAM), a novel technology where expandable starch based pellets made from extrusion are expanded within a mould cavity into blocks using microwave heating. Foamability or degree of expansion of starch-based pellets during microwave heating was studied comprehensively in terms of: the variation of raw natural materials, the extrusion conditions, the additives and the preconditioning of pellets before foaming. The expansion behaviour, foamed cell structures and mechanical properties of expanded pellets were characterized together with the characterization of microstructure of the extrudate materials and physical properties. Characteristics in microwave assisted moulding of the expandable pellets were then studied in terms of: the interfacial bonding and fusion between foamed pellets, the achievement of uniform heating through a moulded block, the loading of pellets and mould filling during foaming. It has been found that the degree of free expansion during microwave heating of the starch-based pellets is dependent on the degree of cook of starch during extrusion, the better the distructurization of the native starch granules, the higher the foamability in microwave heating. The maximum expansion ratio achieved in this work is 14, corresponding a foam porosity of 93%. Hydrophilic additives such as PYA and glycerol have adverse effect on the foamability due to combination effects of the melting point of the materials, degree of cook of starch in the pellets and water molecular mobility during foaming. Nucleation agents such as talc powder can refine cell structure of the foams and enhance elastic modulus, strength and energy absorption during compression. Addition of salts enhances microwave heating rate, expansion ratio and plasticization of the foam. Foamed blocks can be made using the MAM technology by adequate mould material, pre-treatment of the pellets, and control of initial loading in the mould cavity. This study paved the way for further development of the MAM technology for moulding of starch-based foams.

The content of this thesis was to draw up the literary owerview around Japanese quail breeding and fattening and to execute the practice experiment whitch aim was to analyse the efect of the inclusion of extruded flax seed to the diet for quails.

O arroz integral pigmentado (vermelho ou preto) (Oryza sativa, L.) é saudável. Ambos são nutritivos, possuem elevado teor de compostos bioativos, e apresentam características sensoriais diferenciadas ao arroz integral branco. O grande destaque sob o ponto de vista de composição química é o seu elevado teor de compostos fenólicos, associado à alta capacidade antioxidante. A demanda por arroz pigmentado ainda é reduzida, porém, existe uma tendência e o interesse em agregar valor a esses grãos, produzindo alimentos alternativos como flocos de arroz, cereais matinais e snacks. O objetivo deste estudo foi desenvolver produtos extrusados expandidos a partir de duas novas cultivares comerciais de arroz integral preto (SCS 120 ÔNIX) e vermelho (SCS 119 RUBI), provenientes da Epagri/SC. Na otimização do processo considerou-se as melhores propriedades tecnológicas e a retenção de compostos bioativos. Foi investigado o efeito do processo de extrusão nos fitoquímicos e sua atividade antioxidante, antes e após a extrusão. Além disso, a aceitabilidade de dois produtos finais foi realizada com 150 consumidores. O arroz preto apresentou teores significativamente maiores de macronutrientes (proteínas, fibras e minerais) do que o arroz vermelho. O teor de compostos fenólicos totais (CFT) e flavonoides no arroz preto foi de 25% (569,3 mg eq. ác. ferúlico/100g) e 44% (496,9 mg eq. catequina/100 g), respectivamente, superior ao do arroz vermelho. Os flavonoides são representados principalmente por antocianinas no arroz preto e por proantocianidinas no arroz vermelho. O arroz preto apresentou maior atividade antioxidante. A partir do delineamento composto central rotacional as condições ótimas de extrusão foram de 15,5 e 16% de umidade e de 159 e 150ºC de temperatura, para o arroz preto e vermelho, respectivamente. O processo de extrusão resultou em perdas drásticas de TPC, flavonoides, proantocianidinas e o conteúdo remanescente não foi maior que 14% no arroz vermelho e a atividade antioxidante residual também foi baixa. O arroz preto também foi afetado significativamente pela extrusão mas em menores proporções. A concentração após a extrusão foi de 32 % (TPC), 22% (flavonoides), 11% (antocianinas) e a atividade antioxidante remanescente de 40% e 30% pelos métodos de ORAC e DPPH, respectivamente. Quanto à análise sensorial, os extrusados obtidos de arroz preto e vermelho não tiveram diferença significativa na aceitação (p&#8804;0,05). As notas médias atribuídas por 150 provadores para todos os atributos avaliados ficaram situadas no intervalo de 4,8 a 7,7 (correspondente as categorias \"nem gostei/nem desgostei\" a \"gostei muito\") da escala hedônica de 9 pontos. Altos valores de aceitabilidade (maiores que 70%) foram observados para formato, tamanho, cor e crocância no cereal seco e consistência no cereal com leite. A menor aceitabilidade (60%) foi notada no sabor. Isto pode ser explicado pela ausência de aromatizante e/ou edulcorante na formulação. Ainda, foi observado que 26% dos provadores certamente comprariam ambos os extrusados. A farinha de arroz pigmentado é uma alternativa para a elaboração de cereais matinais extrusados na qual apresentam coloração própria, boas características nutricionais e sensoriais, além de ser um produto isento de glúten. / Whole pigmented rice (black and red) (Oryza sativa, L.) is a healthy food. Both types present are nutritious and present high contents of bioactive components, and show distinguishing sensorial properties, unlike those found in whole white rice. However, the most noticeable difference regarding the chemical composition of black and red rice is their high content of phenolic compounds, associated to a high antioxidant activity. Consumption of pigmented rice is still low, but there is an increasing trend and interest in adding value to pigmented grains, producing alternative food products such as rice flakes, breakfast cereals and snacks. Then, the objective of this study was to produce extruded rice from whole grain of black (SCS 120 ÔNIX) and red rice (SCS 119 RUBI). Rice cultivars were grown at experimental fields of Epagri/SC. The conditions of the extrusion process were optimized to achieve the best technological properties and to attain the retention of bioactivties. The phytochemical composition antioxidant activity and technological properties of the pigmented rice flour were investigated before and after extrusion. In addition, the acceptability of the two selected final products was assessed by 150 consumers. The black rice showed significantly higher contents of macronutrients (protein, fiber and minerals) than red rice. The total phenolic compounds (TPC) and total flavonoids in black rice were also 25% (569.3 mg eq. ac. ferulic/100 g) and 44%, (496.9 mg eq. catechin/100 g) respectively, higher than in red rice. In black rice flavonoids were represented mainly by anthocyanins, while in red rice the main flavonoids were proanthocyanidins. Black rice showed the highest antioxidant activity. The predicted optimum extrusion conditions were settled down at 15.5 and 16 % of moisture and 159 and 150ºC of temperature for black and red rice, respectively. The extrusion process induced a drastic loss of TPC, flavonoids and proanthocyanidins and remaining contents were not higher than 14% in red rice and residual antioxidant activity was also very low. Black rice was also significantly affected by the extrusionm but in a lesser degree. The concentration after extrusion was 32% (TPC), 22 % (flavonoids), 11% (anthocyanins) and a remaining 40 % and 30 % antioxidant activity by ORAC and DPPH methods, respectively. Consumer acceptability of extrudates was similar and the average scores awarded were located between 4.8 to 7.7 (corresponding to the categories \"not liked/disliked to \"liked so much\") for all attributes evaluated in the 9-point hedonic scale. High acceptability scores (higher than 70 %) were observed for shape, size, color and texture hardness in dry extrudates and consistency in extrudates with milk. The lowest acceptability (60 %) was noted for flavor. It could be explained because of the extrudates were not flavoured. Furthermore, it was shown that 26 % of consumers certainly would buy both extrudates. The pigmented rice flour demonstrated to be a good alternative to produce extruded breakfast cereals which had his own color, showed good nutritional and sensory properties, besides being a gluten-free product.

CAPES / Passion fruit when processed to obtain the juice, the seeds and the pulp that separate the pith are removed, then getting the shell and the inside white (mesocarp), which is known to be rich in pectin (hemicellulose) Soluble fiber type (a bit more than 50% hemicellulose). Products found passion resulting from the processing of fruit juices in agribusiness, is on the market in passion fruit flour, which is rich in pectin, marketed as products rich in fiber. The peels of fruits consist primarily of carbohydrates, proteins and pectins, which allows the use thereof for the manufacture of sweets, can become a viable alternative to solve the waste disposal problem in addition to increasing their commercial value. The objective of this study was to use passion fruit peel and albedo for the development of a mixed flour precooked rice flour and passion fruit using extrusion technology and then use it as ingredients for producing a beverage, with and without gluten high fiber content. The experimental design was of the type central composite by three factors and verified the effect of these three temperature levels in the last extrusion zone (140, 160 and 180 ? C); Moisture flour (16, 17, 18%) and percentage of passion fruit flour/rice (5:95, 10:90 and 15: 85%). They were carried out physico-chemical analysis, microbilogicas, rheological and sensory in extruded flours and in the elaborate drinks. In general, the results obtained in this study show that passion fruit peel, by-product the juice and pulp industry, could be used as a source of fiber. Its incorporation in food formulation must address their physical, chemical and sensory, to ensure its best use and acceptance among consumers. The results showed that the composition of view flours have significant nutritional value, for both the protein content and to the profile of minerals. The results of microbiological analysis showed that all blends (F1, F6, F10 and F19) were within the microbiological standards recommended by the RDC 12 for this category of products and are fit for human consumption until 45 days of manufacture in temperature environment. Thus, these flours are processed by extruding into an excellent alternative to inclusion of functional ingredients in the diet, may even be used in the preparation of drinks, showing that there acceptability and preference using the same stabilizers pectin and carboxymethylcellulose. / O maracuj? quando processado para obten??o do suco, as sementes e a polpa que as separam do mesocarpo s?o removidas, ficando ent?o a casca e a parte interna de cor branca (mesocarpo), a qual ? conhecida por ser rica em pectina (hemicelulose), fibra do tipo sol?vel (um pouco mais de 50% em hemicelulose). Dos produtos encontrados de maracuj? resultante do processamento de frutas na agroind?stria de sucos, encontra-se no mercado a farinha de maracuj?, a qual ? rica em pectina, comercializados como produtos ricos em fibra. As cascas das frutas s?o constitu?das basicamente por carboidratos, prote?nas e pectinas, o que possibilita o aproveitamento das mesmas para a fabrica??o de doces, podendo se tornar uma alternativa vi?vel para resolver o problema da elimina??o dos res?duos al?m de aumentar seu valor comercial. O objetivo deste trabalho foi utilizar casca e albedo de maracuja para o desenvolvimento de uma farinha mista pr?-cozida de farinha de arroz e maracuja utilizando a tecnologia de extrus?o e posteriormente us?-la como ingredientes para a produ??o de uma bebida, sem gl?ten com e alto teor de fibra. Foi utilizado o delineamento experimental do tipo composto central rotacional por tr?s fatores e verificado o efeito desses tr?s n?veis de temperatura na zona de extrus?o ?ltimo (140, 160 e 180 ? C); umidade farinhas (16, 17, 18%), e percentagem de farinha maracuj? / arroz (5:95, 10:90 e 15: 85%). Foram realizadas analises fisico-qu?micas, microbilogicas, reol?gicas e sensorial nas farinhas extrudadas e nas bebidas elaboradas. Em geral, os resultados obtidos no presente estudo demonstram que a casca do maracuj?, coproduto da ind?stria de sucos e polpas, poderia ser utilizada como fonte de fibras. Sua incorpora??o na formula??o de alimentos deve atentar as suas caracter?sticas f?sicas, qu?micas e sensoriais, para garantir seu melhor aproveitamento e aceita??o entre os consumidores. Os resultados mostraram que do ponto de vista da composi??o as farinhas possuem consider?vel valor nutricional, tanto para o teor de prote?nas como para o perfil de minerais. Os resultados das an?lises microbiol?gicas mostraram que todas as misturas (F1, F6, F10 e F19) encontravam-se dentro dos padr?es microbiol?gicos preconizados pela RDC n? 12 para esta categoria de produtos, estando aptas ao consumo humano at? os 45 dias de fabrica??o em temperatura ambiente. Assim, estas farinhas processadas por extrus?o constituem-se em uma excelente alternativa de inclus?o de ingredientes funcionais na dieta, podendo ser utilizada inclusive na elabora??o da bebidas, mostrando que houve aceitabilidade e prefer?ncia das mesmas utilizando estabilizantes com pectina e carboximetilcelulose.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-08-16T19:30:56Z No. of bitstreams: 1 2014 - Carla da Silva Teba.pdf: 4808769 bytes, checksum: c0f54c8ea9fb94f4469d54eb3764c138 (MD5) / Made available in DSpace on 2017-08-16T19:30:56Z (GMT). No. of bitstreams: 1 2014 - Carla da Silva Teba.pdf: 4808769 bytes, checksum: c0f54c8ea9fb94f4469d54eb3764c138 (MD5) Previous issue date: 2014-09-02 / CAPES / Whey is one the most polluting by-products of the food industry and their perishability does not allow storage for long periods, then it's necessary to find appropriate destination. The whey protein have potential anticarcinogenic, activities hypocholesterolemic, anti-inflammatory, immunomodulatory action, among others. The rice consists mainly of starch, and this structure contributes to the production of snacks high technological quality. The objective of this study was develop and characterize mixed extruded flour of rice and whey protein concentrate aiming use in the manufacture nutritional and practical products. The parameters used in the processing of thermoplastic extrusion were: formulation (% whey protein concentrate), moisture content and temperature of the last heating zone. The extrudates were subjected to physical characterization and functional technology assessment. The highest rates of growth were observed for the tests with up to 4 % whey protein concentrates in their formulations and were processed with low humidity generally less than 20 % and milder temperatures, generally at or below 140 ?C. Through the visual characterization of extruded and the micrographs it was observed that the samples processed with low moisture content (16.64 and 18%) were more homogeneous cells. The X-ray diffraction showed that the profile of the crystal samples is characteristic of type "A" due to the presence of crystalline domains in its structure. The flours viscosity profile is consistent with the characteristics of pre- gelatinized products, being dissolved without needing to cook. The pre-gel flour with blends of rice and whey protein concentrate present viscous, homogeneous and with low capacity of retrogradation. The addiction protein concentrate in rice flour increased the ash and proteins, indicating that the mineral and amino acid composition of the mixed flours may also have a nutritional improvement. Generally, the processing conditions do not significantly affect the nutritional value of the flours blends. The acceptance test performed with the cookies prepared with the mixed flours 8, 10 and 16 (6, 7.36 and 4 % whey protein concentrate, respectively) indicated that the biscuit with a higher content of protein concentrate showed better overall evaluation, taste and purchase intent. The porridges were produced with pre-gelatinized flour containing 2, 4 and 7.36% whey protein concentrate and sensory analysis evaluated the attributes appearance, flavor and consistency, plus purchase intent. The results showed that for most of the evaluated attributes and purchase intent, the sample with higher content of protein concentrate showed the best results. The porridges were produced with pre-gelatinized flour containing 2, 4 and 7.36% whey protein concentrate and sensory analysis evaluated the attributes appearance, flavor and consistency, plus purchase intent. The results showed that for most of the evaluated attributes and purchase intent, the sample with higher content of protein concentrate showed the best results. We conclude that it is possible to produce pre-gel flours containing rice and whey protein concentrate with good nutritional, microbiological and technological features for the production of cookies and porridges rapid dissolution. / O soro de leite ? um dos subprodutos mais poluentes da ind?stria de alimentos e sua natureza perec?vel n?o permite a estocagem por per?odo prolongado, sendo necess?rio encontrar destino adequado aos volumes produzidos. Atribuem-se ?s prote?nas do soro de leite poss?veis atividades anticarcinog?nica, hipocolesterol?mica, anti-inflamat?ria, a??o imunomoduladora, entre outras. O arroz ? constitu?do principalmente por amido, e devido a sua estrutura, contribui para a produ??o de snacks de elevada qualidade tecnol?gica. O objetivo desse trabalho ? desenvolver e caracterizar farinhas mistas pr?-gelatinizadas de arroz e concentrado proteico de soro de leite bovino, obtidas por extrus?o termopl?stica, visando utiliza??o na elabora??o de produtos nutritivos e pr?ticos. Foram consideradas como vari?veis independentes: formula??o (% de concentrado proteico de soro de leite na mistura com farinha de arroz), umidade da mistura da farinha no processamento e temperatura da ?ltima zona de aquecimento. Os extrudados elaborados foram submetidos ? caracteriza??o f?sica e avalia??o tecnol?gica funcional. Os melhores ?ndices de expans?o foram observados para os ensaios com at? 4 % de concentrado proteico e que foram processados com baixa umidade e temperaturas mais brandas. Atrav?s da caracteriza??o visual dos extrudados e das micrografias foi poss?vel observar que as amostras processadas com baixo conte?do de umidade (16,64 % e 18 %) apresentaram c?lulas mais homog?neas. Por meio da difratometria de raios X verificou-se que o perfil das amostras ? caracter?stico ao cristal do tipo "A", devido ? presen?a de dom?nios cristalinos em sua estrutura. As farinhas mistas extrudadas se destacaram por possuir elevada viscosidade a frio, baixa viscosidade a quente (95?C) e baixo poder de retrograda??o. Os resultados observados nos par?metros de viscosidade avaliados mostram correla??o destas propriedades com as caracter?sticas de f?cil reconstitui??o e boa solubiliza??o em meio aquoso, sem a necessidade de cozimento. A incorpora??o de concentrado proteico na farinha de arroz promoveu incremento no teor de cinzas e prote?nas, indicando melhoria na composi??o mineral e de amino?cidos das farinhas mistas. De modo geral, as condi??es de processamento utilizadas n?o afetaram de forma significativa o valor nutricional da maior parte das farinhas mistas produzidas. O teste de aceita??o realizado com os biscoitos elaborados com as farinhas mistas referentes aos ensaios 8, 10 e 16 (6, 7,36 e 4 % de concentrado proteico, respectivamente) indicou que o biscoito com maior teor de concentrado proteico apresentou melhor avalia??o global, sabor e inten??o de compra. Os mingaus foram produzidos com farinhas pr?-gelatinizadas contendo 2, 4 e 7,36 % de concentrado proteico e submetidos ? an?lise sensorial. Para a maior parte dos atributos avaliados e para a inten??o de compra, a amostra com maior teor de concentrado proteico apresentou os melhores resultados. Conclui-se que ? poss?vel produzir farinhas mistas pr?-gelatinizadas de arroz e concentrado proteico de soro de leite bovino com boas caracter?sticas nutricionais, microbiol?gicas e tecnol?gicas tanto para a elabora??o de biscoitos quanto para a produ??o de mingaus de r?pida dissolu??o.

Made available in DSpace on 2015-03-26T13:55:30Z (GMT). No. of bitstreams: 1 texto completo.pdf: 211270 bytes, checksum: 1d453950af1b6efd3aa6a33b18fb16a7 (MD5) Previous issue date: 2003-05-09 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work was carried out at the dairy cows Teaching, Research and extension unit at the Department of Animal Science of the Federal University of Viçosa with the objective of evaluating: the intake and apparent digestibility of nutrients, milk production and composition, ruminal pH and ammonia, ruminal degradability of dry matter and crude protein, urea concentration in the plasma in cows fed ration processed by different methods. Sixteen dairy holstein cows, purebreds and crossbred, in two milk production levels: 30.0 kg/day and 20.0 kg/day, were distributed equitatively in two latin squares balanced for each production level. The experiment was constituted of four periods with duration of 15 days each. The experimental diets were isoproteic, based on corn silage with forage: concentrate ratio of 50:50 to the level of 30.0 kg/day and 60:40 to the level of 20.0 Kg/day, in dry matter basis. The treatments were constituted of four concentrate rations: meal form (MR), pelleted (PR) and extruded (ER), with 27% and 84% of crude protein (CP) and total digestible nutrients(TDN), respectively and high energy ration with part of extruded elements (HER), with 27% and 86% of crude protein and TDN, respectively. The animals were housed in individual stalls like Tie Stall and fed ad libitum. The excretion of fecal dry matter was estimated by indigestible acid detergent fiber (ADFi). Rumen fluid was collected by esophagian tube. The urine collection was made by spot test . Blood was collected four hours after the morning feeding, being used heparin as anticoagulant. The in situ degradability was estimated with nylon pockets inside the animal rumen. The dry matter (DM) intake was not different among the experimental diets. Digestibility of the DM there was no difference, but the digestibility of the neutral detergent fiber (44,35%) was lower (P<0,05) to ER (extruded) and digestibility of the crude protein was lower (P<0,05) to ER (72,36%), compare to the MR meal). The milk production was larger (P<0,05) for the extruded diet (ER) (29.0 kg/day), in higher level production, however, in lower level there was no difference. The milk composition was not different among the diet to higher level production. Inside each time (before and three hours after the morning feeding) there was no difference in the pH values and amoniacal nitrogen compounds (N-NH3) among the experimental diets. There was no difference in ruminal N-NH3 concentration on time 0, however, at three hours after feeding, ER presented lower (P<0,05) ruminal N-NH3 concentration. The ruminal degradability of crude protein and DM were higher to PR and especiallly in ER. There was no difference in the concentration of plasmatic urea and fractional urine excretions. / O presente trabalho foi realizado na Unidade de Ensino, Pesquisa e Extensão em Gado de Leite do Departamento de Zootecnia, na Universidade Federal de Viçosa, objetivando avaliar: o consumo e a digestibilidade aparente dos nutrientes, a produção e composição do leite, o pH e a amônia ruminal, a degradabilidade ruminal da matéria seca e proteína bruta, e concentração de uréia no plasma e excreções urinárias de vacas leiteiras alimentadas com diferentes formas de processamento da ração concentrada. Foram utilizadas 16 vacas da raça holandesa, puras e mestiças, em dois níveis de produção de leite: 30,0 kg/dia e 20,0 kg/dia, que foram distribuídas equitativamente em dois quadrados latinos balanceados para cada nível de produção. O Experimento foi constituído por quatro períodos, com duração de 15 dias cada. As dietas experimentais foram isoprotéicas, constituídas à base de silagem de milho (Zea mays) com relação volumoso: concentrado de 50:50 para o nível de 30,0 kg/dia e 60:40 para o nível de 20,0 kg/dia, com base na matéria seca. Os tratamentos foram constituídos de quatro rações concentradas sendo: ração farelada (RF); ração peletizada (RP) e ração extrusada (RE), com 27% com de proteína bruta (PB) e 84% de nutrientes digestíveis totais (NDT) e ração de alta energia parcialmente processada (RAE), com 27% de PB e 86% de NDT. Os animais foram mantidos em baias individuais do tipo Tie Stall , onde receberam alimentação ad libitun. A excreção de matéria seca fecal foi estimada através da fibra em detergente ácido indigestível (FDAi). O líquido ruminal foi coletado, utilizando-se sonda esofágica. A coleta de urina foi feita através do 4 h após a alimentação. Foi coletado sangue quatro horas após a alimentação matinal, utilizando-se heparina como anticoagulante. A degradabilidade foi estimada através da técnica in situ utilizando-se sacos de náilon incubados no rúmen animal. O consumo de matéria seca (CMS) não diferiu entre os tratamentos RF, RP e RE. A digestibilidade da matéria seca (DMS) não foi afetada pelo processamento, enquanto a digestibilidade da proteína bruta para vacas alimentadas com ração extrusada (RE) (72,36%), foi menor (P<0,05), comparada a ração farelada (RF), no nível de 50 % de concentrado. A digestibilidade da fibra em detergente neutro para vacas alimentadas com RE (44,35%) foi menor (P<0,05) no nível de 50 % de concentrado. A produção de leite foi maior (P<0,05) para os animais consumindo ração extrusada (29,9 kg/dia), no nível de 50 % de concentrado, contudo, o menor nível não apresentou diferença significativa. A composição do leite não diferiu entre os tratamentos, para ambos os níveis de produção. Dentro de cada tempo (antes e três horas após a alimentação matinal), não houve diferenças nos valores de pH. Para as concentrações de N - NH3 ruminal, imediatamente antes da alimentação, as concentrações não diferiram entre si. Contudo, a ração extrusada apresentou menor (P<0,05) concentração de N - NH3 ruminal três horas após a alimentação. A degradabilidade ruminal da proteína bruta e da matéria seca foi numericamente maior para o tratamento peletizado e, principalmente, para o tratamento extrusado. As concentrações de uréia plasmática as excreções urinárias não diferiram entre os tratamentos.