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In this study we determined the impact of increasing dietary whole cottonseed (WCS) on rumen fermentation, nutrient digestibility, and microbial community composition. This study contributes novel information to the dairy community deepening the understanding of how including different levels of WCS can affect the rumen environment. This research was conducted in continuous culture fermenters. Treatments included a control diet without WCS, or the control diet plus 5, 10, or 15% (dry matter) WCS. The control diet was a 50:50 orchardgrass hay:concentrate mixture fed twice daily. In the second experiment, soybean meal and cottonseed meal (CSM) were included, and rations were balanced for fiber and protein. For the first experiment, no treatment effect was observed for neutral detergent fiber (NDF) or starch digestibility, or for acetate concentration. Butyrate and ammoniacal nitrogen concentrations increased, while propionate concentration tended to decrease as WCS was added. Increasing WCS in the diet decreased protozoa count and relative abundance of archaea. Firmicutes abundance increased whereas Bacteriodetes decreased with the addition of WCS. Lachnospiraceae and Prevotellaceae were the most abundant bacteria families in all the samples. The two most abundant genera across samples were Prevotella and Pseudobutyribrio, and the addition of WCS decreased the abundance of both. For the second experiment, with diets adjusted for fiber and protein, inclusion of WCS did not affect NDF digestibility or ammonia production. Acetate and propionate decreased with the addition of WCS while no treatment effect was observed for butyrate production. Bacteria population increased with inclusion of WCS while the opposite was observed for archaea. Our results indicate that increasing levels of WCS up to 15% (dry matter) diet do not negatively impact fiber and starch digestion in the rumen. Furthermore, inclusion of WCS at affected the microbial community composition at different levels. In conclusion, supplementation of WCS had an overall positive impact on the rumen as it did not affect rumen fermentation or nutrient digestibility, and it increased bacteria population and decreased archaea concentrations.

Supplementary Material of the article "Methane-related community of a carbonate-enriched pockmark, Brazilian Southeastern continental slope" -SF1. Sediment sampling in Box-corer, presenting the core positioning and sediment surface color -SM1. Organic compounds - Analytical procedures -SM2. Sediment dark carbon fixation (DCF) and Heterotrophic Microbial Production (HMP) - Analytical procedures -SF2. Rarefaction curve -SM3. Methodology details for the functional prediction database -ST1. ASVs alpha diversity indexes grouped by enrichment type and incubation time -SF3. Microbial community composition of deep-sea sediments of a pockmark of the Brazilian Southeastern Atlantic enriched with methane. Sequences were taxonomically classified using the Silva database v. 138 -SF4.Upset Plot composed by bacterial and archaeal ASVs detected on the harvesting times of the methane incubation of deep-sea intact pockmark sediment cores of Brazilian SE Atlantic. Blacklinesconnectingcirclesindicatesharedtaxonomies. Black points solely indicate unique taxonomy presence per set. Vertical bars indicate intersection size (number of complete taxonomies, up to Species from the assignment with Silva v.138) on each set. Datasets: Control_16h, cores without CH4 input harvested after 16h; Control_940h, core without CH4 input harvested on 40th day; Enriched_16h, core with CH4 input harvested after 16h; Enriched_120h, core with CH4 input harvested on the 5th day; Enriched_240h, core with CH4 input harvested on the 10th day; Enriched_720h, core with CH4 input harvested on the 30th day; Enriched_960h, core with CH4 input harvested on the 40th day. -SF5. Methane-enriched differentially abundant taxa recovered with ANCOM statistics

Supplementary Materials Methane-related community of a carbonate-enriched pockmark, Brazilian Southeastern continental slope

El continuo crecimiento en el mercado de la cerveza artesanal, y el aumento del interés y las exigencias de los consumidores, han orientado los esfuerzos del sector hacia la producción de cervezas diferenciales e innovadoras. En este punto, las levaduras no convencionales, distintas de las levaduras cerveceras tradicionales S. cerevisiae (ale) y S. pastorianus (lager), han cobrado gran protagonismo como herramientas para el desarrollo de nuevos productos. De gran interés resulta la especie criotolerante S. eubayanus, aislada por primera vez en la Patagonia Argentina e identificada como uno de los parentales de la especie híbrida S. pastorianus (levadura lager). Este trabajo buscó contribuir al conocimiento sobre el comportamiento fermentativo de S. eubayanus, desarrollar cultivos iniciadores aptos para su aplicación en la industria cervecera y evaluar sus estrategias de aplicación a escala productiva. Inicialmente, cinco cepas de S. eubayanus (representativas de las cinco subpoblaciones estructuradas geográficamente) fueron ensayadas en fermentaciones a escala laboratorio evaluándose su capacidad fermentativa (velocidad de fermentación, atenuación, perfil de azúcares consumidos) y su perfil organoléptico (ésteres, alcoholes superiores, fenoles, evaluación sensorial). Las diferentes características fermentativas observadas y la producción diferencial de compuestos volátiles entre las cepas demostraron variabilidad fenotípica intraespecífica. Por su parte, la cepa CRUB 1568T fue seleccionada debido a su buen rendimiento fermentativo, moderada producción de los fenoles 4-vinilguaiacol y 4-vinilfenol, y su aporte de los ésteres frutados hexanoato y octanoato de etilo. A partir de la cepa seleccionada, se buscaron establecer las condiciones de propagación para el desarrollo de cultivos iniciadores para la producción de cerveza. Se evaluaron distintas técnicas para la determinación de la viabilidad y vitalidad de los inóculos, seleccionándose el método de tinción con violeta de metileno alcalino y las fermentaciones a escala laboratorio, respectivamente. Se seleccionó un medio de cultivo a base de extracto de malta comercial, cuya composición fue optimizada evaluando 9 factores con dos niveles, a través de un diseño experimental del tipo Plackett-Burman. Dos factores mostraron influencia significativa sobre la producción de biomasa (extracto de levadura y peptona ácida de caseína), y fueron posteriormente optimizados mediante un Diseño Central Compuesto, a través de la Metodología de Superficie Respuesta. Con el medio de cultivo optimizado (medio extracto de malta con 0,31 % p/v de extracto de levadura y 0,12 % p/v de peptona ácida de caseína) logró obtenerse una producción de biomasa igual a la del medio sin optimizar (12 g/L), pero con una reducción de costos del 40 %. Por último, se realizó el escalado de la propagación a 20 L, obteniéndose cultivos de S. eubayanus puros y de calidad, de tamaño suficiente como para inocular fermentadores de hasta 700 L. Previo al traspaso de los cultivos iniciadores al sector cervecero, se evaluó la interacción de S. eubayanus con el lúpulo. Para ello, se estudió el comportamiento fermentativo de la cepa CRUB 1568T en mostos sin lupular y lupulados, así como el impacto de la levadura en el amargor medido (IBU, por sus siglas en inglés) y en la percepción sensorial del amargor. S. eubayanus presentó tolerancia a los compuestos del lúpulo (20 y 60 IBUs), observándose incluso una velocidad de fermentación aumentada en mostos lupulados (del 34 % y 62 %, respectivamente). Por su parte, los IBUs obtenidos para cervezas fermentadas con S. eubayanus resultaron superiores que para las cepas industriales (18 % mayor), siendo esta diferencia notoria sensorialmente e incluso percibida como un amargo áspero (harsh). Estos resultados permiten adoptar criterios para su aplicación y predecir adecuadamente el perfil final de las cervezas producidas con esta levadura. Posteriormente, S. eubayanus CRUB 1568T fue ensayada a escala semi-piloto de 20-40 L en mosto cervecero, obteniéndose un comportamiento similar a lo observado a escala laboratorio. Sin embargo, cuando esta levadura salvaje se aplicó a escala productiva (1000-1500 L), mostró un bajo rendimiento de fermentación. Las fermentaciones se completaron en 20 días (prácticamente el doble de tiempo que a escala laboratorio y semi-piloto) con una atenuación promedio del 30 % (la mitad de lo observado previamente). Se decidió evaluar si un aumento en el suministro de oxígeno durante la fermentación podría ayudar a mejorar el rendimiento fermentativo a mayor escala. Se encontró una mejora en la eficiencia de la fermentación aplicando distintos regímenes de oxigenación, llegando a obtenerse fermentaciones completas en 5-7 días, con niveles de atenuación del 60 %. Este trabajo fomenta el uso de levaduras no convencionales en la elaboración de cerveza. La selección de levaduras autóctonas del ambiente representa un valioso recurso, no sólo para el desarrollo de cervezas innovadoras con mayor diferenciación productiva, sino que abre la posibilidad de otorgar un carácter regional al producto, con una consecuente mejora en la competitividad para el sector. Encontramos que la aplicación de estas levaduras en la industria requiere de un manejo diferente al de las levaduras cerveceras tradicionales, abriéndose así un punto de partida para continuar con investigación y experimentación en relación a las diferentes estrategias que se pueden abordar. The continuous growth in the craft beer market, and the increased interest and demands of consumers, have directed the efforts of brewers towards the production of differential and innovative beers. In this sense, non-conventional yeasts - other than the traditional domesticated ale (Saccharomyces cerevisiae) and lager (Saccharomyces pastorianus) yeasts - have gained attention as tools for new product development. Of great interest is the cryotolerant species S. eubayanus, isolated for the first time in Patagonia (Argentina) and identified as one of the parents of the hybrid species S. pastorianus (lager yeast). This work sought to contribute to the knowledge about the fermentative behavior of S. eubayanus, develop starter cultures suitable for the brewing industry, and evaluate different strategies for its application on a productive scale. First, five strains of S. eubayanus (representative of the five geographically structured subpopulations) were tested in laboratory-scale fermentations, evaluating their fermentation performance (fermentation rate, attenuation, sugars consumption) and their organoleptic profile (esters, higher alcohols, phenols, sensory evaluation). The different fermentative characteristics observed and the differential production of volatile compounds between the strains demonstrated intraspecific phenotypic variability of the species. The strain CRUB 1568T was selected due to its good fermentation performance, moderate production of phenols (4-vinylguaiacol and 4-vinylphenol), and its contribution of the fruity ester’s ethyl hexanoate and ethyl octanoate. From the selected strain, it was sought to establish the propagation conditions for the development of starter cultures for brewing. Different techniques were evaluated to determine the viability and vitality of the biomass produced, selecting the alkaline methylene violet staining method and laboratory-scale fermentations, respectively. A culture medium based on commercial malt extract was selected and optimized by evaluating 9 factors, with two levels for each factor, through an experimental Plackett-Burman design. Two factors showed significant influence on biomass production (yeast extract and acid casein peptone), and were later optimized by a Central Composite Design, through Response Surface Methodology. With the optimized culture medium (malt extract medium with 0.31 % w/v of yeast extract and 0.12 % w/v of acid casein peptone) it was possible to obtain a biomass production equal to that of the non-optimized medium (12 g/L), but with a 40 % a cost reduction. Finally, the propagation was scaled-up to 20 L, being able to obtain pure and quality S. eubayanus cultures, with adequate cell density to inoculate fermenters of up to 700 L. Prior to transfer the starter cultures to the brewing industry, the interaction of S. eubayanus with hops was evaluated. For this, the fermentation performance of S. eubayanus CRUB 1568T in hopped and unhopped wort was studied, as well as the impact of the yeast on the measured (IBU) and sensory perception of bitterness. S. eubayanus showed tolerance to hop compounds (20 and 60 IBUs), presenting even an increased fermentation rate in hopped worts (34 % and 62 %, respectively). On the other hand, the IBUs obtained for beers fermented with S. eubayanus were 18 % higher than for the industrial strains, with this difference being notorious sensorially and even perceived as a harsh bitterness. These results allow us to adopt criteria for the application of S. eubayanus in brewing, and adequately predict the final profile of the beers produced with this yeast. Subsequently, S. eubayanus CRUB 1568T was tested on brewing wort at a semi-pilot scale (20-40 L), observing a similar behavior to that obtained in the laboratory. Nevertheless, when this wild yeast was applied on a productive scale (1000-1500 L), it showed a poor fermentation performance. Fermentations were completed in 20 days (almost twice as long as laboratory and semi-pilot scales) with an average attenuation of 30 % (half of what was previously observed). It was decided to test whether an increase in oxygen supply during fermentation could help improve fermentation performance on a larger scale. An improvement in fermentation performance was found by applying different oxygenation regimens, achieving complete fermentations in 5-7 days, with attenuation levels of 60 %. This work encourages the use of non-conventional yeasts in brewing. The selection of native yeasts from the environment represents a valuable resource, not only for the development of innovative beers with greater productive differentiation, but also opens the possibility of conferring regional character to the product, with a consequent improvement in competitiveness. It was certainly found that the application of these yeasts in the industry requires different handling than traditional brewing yeasts, and opens a starting point for research and experimentation in relation to the different strategies that can be addressed. Fil: Burini, Julieta Amalia. Universidad Nacional del Comahue. Centro Regional Universitario Bariloche; Argentina.

Рассмотрено состояние и предложены пути комплексного решения проблемы переработки сельскохозяйственных отходов как вновь формирующейся отрасли по утилизации таких отходов в увязке с развитием зарождающейся отрасли производства органической продукции и рынка органических удобрений. Проблема рассмотрена во взаимосвязи регуляторной, экономической и технологической компонент в их динамике от текущего состояния к целевому (желаемому). Предложены конкретные меры для стимулирования взаимосвязанного развития отрасли переработки отходов в органические удобрения и отрасли производства органической продукции. Особое внимание уделено приоритетным технологиям переработки отходов в органические удобрения, механизмам пилотирования и масштабирования российских технологий для их ускоренного применения в сельском хозяйстве., The state is examined and ways of a comprehensive solution to the problem of processing agricultural waste as a newly emerging industry for the disposal of such waste, in conjunction with the development of the nascent branch of organic production and the market of organic fertilizers, are proposed. The problem is considered in the relationship of the regulatory, economic and technological components in their dynamics from the current state to the target (desired). Concrete measures are proposed to stimulate the interconnected development of the industry for processing waste into organic fertilizers and the organic production industry. Particular attention is paid to priority technologies for processing waste into organic fertilizers, to piloting and scaling up Russian technologies for their accelerated application in agriculture., Экономика и предпринимательство, Выпуск 9 (122) 2020

Рассмотрено состояние и предложены пути комплексного решения проблемы переработки сельскохозяйственных отходов как вновь формирующейся отрасли по утилизации таких отходов в увязке с развитием зарождающейся отрасли производства органической продукции и рынка органических удобрений. Проблема рассмотрена во взаимосвязи регуляторной, экономической и технологической компонент в их динамике от текущего состояния к целевому (желаемому). Предложены конкретные меры для стимулирования взаимосвязанного развития отрасли переработки отходов в органические удобрения и отрасли производства органической продукции. Особое внимание уделено приоритетным технологиям переработки отходов в органические удобрения, механизмам пилотирования и масштабирования российских технологий для их ускоренного применения в сельском хозяйстве., The state is examined and ways of a comprehensive solution to the problem of processing agricultural waste as a newly emerging industry for the disposal of such waste, in conjunction with the development ofthe nascent branch of organic production and the market of organic fertilizers, are proposed. The problem is considered in the relationship of the regulatory, economic and technological components in their dynamics from thecurrent state to the target (desired). Concrete measures are proposed to stimulate the interconnected development of the industry for processing waste into organic fertilizers and the organic production industry. Particular attention is paid to priority technologies for processing waste into organic fertilizers, to piloting and scaling upRussian technologies for their accelerated application in agriculture., Экономика и предпринимательство, Выпуск 8 (121) 2020

The current understanding of the transport phenomena involved in the operation of industrial fermenters is not sufficient. This is reflected by the limitations seen in their design and operation. A better insight in the local processes taking place (hydrodynamics, gas dispersion, mixing, microbial kinetics) is required to be able to make a step change in the design of those reactors. At the scale of industrially relevant fermenters, experimental methods become quickly limited when detailed information is needed. It was the aim of this research to provide a framework where such information could be gained by means of Computational Fluid Dynamics (CFD) simulations with a manageable computational burden so that it could readily be used by the industrial practitioners. The main focus of this thesis is on the hydrodynamics of bubbly flows in stirred reactors, although, scalar mixing and substrate uptake kinetics studies were also conducted. Because the literature on the standard configured lab/pilot scale single-impeller reactors is vast and the experimental data is abundant, we chose to start with such a system first and, with the learnings gained, moved ultimately to realistic industrial scale multi-impeller fermenters. We also limited ourselves to Rushton type radial pumping disk turbine systems, again on the basis of available data for validation, and also due to time limitations.

La fermentación del cacao durante el proceso de beneficio es una etapa que determina la calidad final del grano. En este sentido, este trabajo se desarrolló con 3 estudios acerca de cómo influye de la fermentación sobre algunas características finales de los granos de cacao. Los estudios se llevaron a cabo en 3 lugares geográficos diferentes. El primer se realizó en el departamento de Arauca y tuvo como objetivo identificar las principales actividades que desarrollan los agricultores de la región durante la fermentación y cómo estas actividades determinan la calidad fisicoquímica y sensorial del grano. El segundo estudio tuvo lugar en la isla de Trinidad y Tobago, allí se evaluaron dos sistemas de fermentación; un fermentador rotatorio y un cajón de madera. Por último se determinó la influencia de la frecuencia de volteo y la duración de la fermentación sobre los granos de cacao; este último estudio se hizo en la ciudad de Medellín con cacao cosechado en el municipio de San Roque-Antioquia. Abstract: The cocoa fermentation during the process of postharvest is a stage that determines the final quality of the cocoa beans. In this sense, this work was developed with 3 studies about how influences the fermentation on some final characteristics of the cocoa beans. The studies were conducted in 3 different geographic locations. The first was carried out in the department of Arauca and aimed to identify the main activities developed by farmers in the region during fermentation and how these activities determine the physical and chemical quality of the cocoa beans. The second study was done in Trinidad and Tobago Island, where two fermentation systems were evaluated; a rotary fermenter and a wooden Box fermenter. Finally, the influence of the turning frequency and the duration of the fermentation on the cacao beans were determined; this last study was done in Medellin city with cacao harvested in the San Roque-Antioquia city Maestría

This investigation had as an objective to evaluate types of fermenters and different times of fermentation used by cocoa producers from the central and north zone of Manabi province, Ecuador. Four fermenters were used: burlap sack, piles, wooden boxes and plastic vat with the ability to store 60 kilos of cocoa and fermentation times ranging from 2 to 5 days; a control was evaluated in addition (without fermentation). A Completely Randomized Blocks Design with additive factors arrangement with three replications was used. The data were analyzed using analysis of variance with Tukey test at 5% probability. Physical variables were analyzed: percentage of fermented, violet and slate (test cutting) grains; and chemical: polyphenols (photometry 760 nm), volatile acidity (steam stripping) and theobromine, caffeine (High Performance Liquid Chromatography, HPLC). The analysis of the results shows that the fermentation time unlike the type of fermenter, had an influence on the chemical and physical variables analyzed. The increased percentage of fermented beans and decreased violet grains occurred from the beginning until the end of fermentation. The chemical quality improves by reducing the concentration of alkaloid compounds and polyphenols, which impacts on the sensory characteristics of Nacional cocoa type. Of the fermenters and the times used by producers the best quality characteristics are presented between four and five days of fermentation in wooden boxes. La presente investigación tuvo como objetivo evaluar los tipos de fermentadores y los diferentes tiempos de fermentación usados por los productores de cacao de la zona norte y central de la provincia de Manabí-Ecuador. Se estudiaron cuatro fermentadores: saco de yute, montón, caja de madera y tina plástica, con una capacidad para almacenar 60 kg de cacao y tiempos de fermentación de 2 a 5 días; además, se evaluó un testigo (sin fermentar). El diseño fue bloques completos al azar en arreglo factorial aditivo con tres réplicas. Los datos se analizaron mediante análisis de varianza con la prueba de Tukey al 5% de probabilidades. Se analizaron variables físicas: porcentaje de granos fermentados, violeta y pizarrosos (prueba de corte); y químicas: polifenoles (fotometría 760 nm), acidez volátil (arrastre de vapor) y teobromina-cafeína (Cromatografía Líquida de Alta resolución, HPLC). El análisis de los resultados muestra que el tiempo de fermentación a diferencia del tipo de fermentador, tuvo influencia sobre las variables físicas y químicas analizadas. El aumento del porcentaje de granos fermentados y la disminución de los granos violetas ocurrieron desde el inicio hasta el final de la fermentación. La calidad química mejora con la reducción de la concentración de compuestos alcaloides y polifenoles, lo que repercute sobre las características organolépticas del cacao tipo Nacional. De los fermentadores y los tiempos utilizados por los productores se presentan las mejores características de calidad entre los cuatro y cinco días de fermentación en cajas de madera.

The objective of this study was to evaluate the effects of forage level and oil supplement on selected strains of rumen bacteria believed to be involved in biohydrogenation (BH). A continuous culture system consisting of four fermenters was used in a 4×4 Latin square design with a factorial arrangement of treatments, with four 10 d consecutive periods. Treatment diets were: i) high forage diet (70:30 forage to concentrate (dry matter basis); HFC), ii) high forage plus oil supplement (HFO), iii) low forage diet (30:70 forage to concentrate; LFC), and iv) low forage plus oil supplement (LFO). The oil supplement was a blend of fish oil and soybean oil added at 1 and 2 g/100 g dry matter, respectively. Treatment diets were fed for 10 days and samples were collected from each fermenter on the last day of each period 3 h post morning feeding. The concentrations of vaccenic acid (t11C18:1; VA) and c9t11 conjugated linoleic acid (CLA) were greater with the high forage diet while the concentrations of t10 C18:1 and t10c12 CLA were greater with the low forage diet and addition of oil supplement increased their concentrations at both forage levels. The DNA abundance of Anaerovibrio lipolytica, and Butyrivibrio fibrisolvens vaccenic acid subgroup (Butyrivibrio VA) were lower with the low forage diets but not affected by oil supplement. The DNA abundance of Butyrivibrio fibrisolvens stearic acid producer subgroup (Butyrivibrio SA) was not affected by forage level or oil supplement. In conclusion, oil supplement had no effects on the tested rumen bacteria and forage level affected Anaerovibrio lipolytica and Butyrivibrio VA.

1 Página.--Trabajo presentado al 2010 Annual Meeting Abstracts (Denver, Colorado, 11 al 15 de Julio del 2010).--J. Anim. Sci. Vol. 88, E-Suppl. 2/J. Dairy Sci. Vol. 93, E-Suppl. 1/Poult. Sci. Vol. 89, E-Suppl. 1, This study was designed to compare the effects of 4 diets on bacterial communities in bacterial pellets (BP) isolated from the solid (SAB) and liquid phase (LAB) of the rumen of sheep with those observed in Rusitec fermenters. The 4 experimental diets had forage:concentrate ratios (F:C) of 70:30 (HF) or 30:70 (HC) and alfalfa hay or grass hay as forage (FOR). SAB and LAB were isolated from each sheep (4 per diet) and fermenter (n = 4) immediately before feeding, and bacterial diversity was analyzed by ARISA-PCR of the 16S ribosomal DNA. A total of 170 peaks were detected in the ARISA electropherograms across the full set of 64 BP. The number of peaks (NP) in BP from sheep ranged from 42 to 82 for LAB, and from 31 to 81 for SAB (168 peaks in total). In fermenters, NP ranged from 53 to 79 for LAB, and from 21 to 69 for SAB (162 peaks in total). No effect of F:C (P > 0.05) on NP or Shannon index (SI) was observed on LAB in any system. F:C did not affect SAB profile in fermenters, but NP and SI were greater (P < 0.05) in SAB from sheep fed HF diets compared with those from HC-sheep. Feeding grass hay diets promoted greater (P < 0.01) SAB diversity in both systems compared with alfalfa hay diets. FOR did not (P > 0.05) affect LAB profile in sheep, but grass hay-fed fermenters had greater (P < 0.01) LAB diversity compared with fermenters fed alfalfa hay diets. The results indicate that bacterial diversity was more markedly affected by FOR than by F:C. There was a positive relationship (P = 0.001) between the NP in LAB and that in SAB in Rusitec, but no relationship (P = 0.72) was found in sheep; this would indicate that dietary effects on bacterial diversity were similar in LAB and SAB in fermenters, but contrasting in sheep. When all samples were analyzed together by clustering analysis, 2 distinct clusters were observed for in vivo and in vitro BP, which suggests a different structure of the bacterial communities in sheep and fermenters.

Made available in DSpace on 2014-06-11T19:25:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-25Bitstream added on 2014-06-13T19:32:32Z : No. of bitstreams: 1 silveira_rg_me_bauru.pdf: 2564361 bytes, checksum: 59979913e85e47f8a21eb524c379df8e (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) A fermentação alcólica, processo central da indústria cervejeira é um processo que libera uma grande quantidade de calor. Sendo assim, os recipientes de fermentação devem estar equipados com instalações de refrigeração para o correto controle da temperatura. A presente pesquisa tem como objetivo a análise da troca de calor de fermentadores cilindrocônicos dotados de sistema de refrigeração direta através de serpentina meia-cana. Para a consecução desse objetivo foi necessária a elaboração de um roteiro de cálculo seguro baseado em equações e experiências encontradas em renomadas literaturas. A análise dos resultados encontrados foi realizada a partir dos valores obtidos através do programa de cálculo atualmente utilizado em uma das maiores empresas fornecedoras deste tipo de equipamento para o mercado cervejeiro, a Dedini Indústrias de Base. Constatou-se que os valores obtidos pelo roteiro apresentado na presente dissertação foram maiores do que os calculados no programa, concluindo-se que as diferenças e dificuldades de resfriamento encontradas em equipamentos semelhantes fornecidos a clientes distintos podem ter origem na quantidade de refrigerante. As estimativas para o coeficiente global de transferência de calor independem do roteiro de cálculo seguido, pois há uma variação máxima de 3,5 % nos resultados para o cálculo deste. O mesmo é verificado para as vazões mássicas de amônia requerida, onde esta variação é ainda menor (cerca de 3,0%) Alcoholic fermentation, brewery industry's central process that liberates a great amount of heat. Therefore, the fermentation containers should be equipped with cooling installations for correct temperature control. The present research aims to analyze the heat exchange in cylindroconical fermenters endowed with a halp-pipe coil direct cooling system. To achieve this objective, the elaboration of a sate calculation route based on equations and experiences found in renowned references was necessary. The validation of the results was accomplished from the values obtained through the calculation program now used in one the largest supplying companies of this kind of equipment for the brewer market, Dedini indústrias de Base. It was verified that the flow of ammonia for the cooling system obtained by the itinerary introduced in the present article was larger than the one calculated in the program, and it can be concluded that the differences and cooling difficulties found in similar equipments supplied to different customers can have origin in the amount of ammonia used in the cooling system. The values for the overal heat transfer coefficient do not depend on the calculation itinerary followed, because there is a maximum variation of 3.5% in the results for the calculation of the coeffiecient. The same is verified for the mass flows of requested ammonia, where this variation is still smaller (about 3.0%)

En fermentaciones aerobias uno de los nutrientes que se constituye en limitante es el oxígeno, del cual la transferencia esta afectada por variables como el tamaño de burbuja, la temperatura, la presión, las propiedades del medio líquido, la concentración de oxígeno en el gas, la potencia transferida por la agitación, entre otras. En este trabajo se diseño, construyó y evaluó un aireador externo acoplado a fermentadores del tipo tanque agitado. Se empleó como modelo biológico una fermentación aeróbica con un Lactococcus sp que presenta extrema limitación de oxígeno. El sistema de aireación externo emplea un microburbujeador de acero sinterizado y recirculación de medio de cultivo, aumentando la presión y disminuyendo el diámetro de la burbuja. La caracterización mediante análisis dimensional de éste dispositivo permite su implementación en otros cultivos con microorganismos aerobios con alta demanda de oxígeno o células de mamíferos de alta sensibilidad a esfuerzos de corte. Se determina que las variables que tienen efecto significativo sobre el coeficiente volumétrico de transferencia de oxígeno-kLa- son la agitación y el flujo de recirculación, aumentando el kLa desde valores de 20.16(h-1) en el fermentador convencional con aireación interna, hasta valores de kLa de 90 (h-1) con el aireador externo. Se comprueba que el dispositivo es un sistema de alta tasa de transferencia de oxígeno. El estudio incluye las cinéticas de crecimiento y los valores de kLa medidos por la técnica dinámica durante la fase exponencial, para diferentes condiciones de operación, encontrando una condición base donde se elimina la limitación de oxigeno. Además presenta un análisis adimensional de las variables y su correlación con los datos experimentales. / Abstract. The aerobic fermentations usually have oxygen limitation. The oxygen transfer is affected by variables such as bubble size, temperature, pressure, culture medium properties, the concentration of oxygen, agitation rate, and others. This work is oriented to design, built and evaluates an external aerator in stirred tank fermenters. Lactococcus sp was used as biological model an aerobic fermentation, which has extreme oxygen limitation. The system uses an external sintered steel microbubbles diffuser and medium recirculation, it increase pressure and decrease bubble diameter. The characterization by dimensional analysis allows system implementation in other aerobic culture with high oxygen demand or high shear stress sensitive cells like mammalian cells. The highest effect on the volumetric oxygen transfer coefficient -kLa-is caused by agitation rate and recirculation flow, increasing the values of kLa from 20.16 (h-1) in the fermenter conventional with internal aeration until kLa values of 90 (h-1) with external aerator. It is verified that the device is a high rate oxygen transfer system. The study includes the kinetics of growth and kLa values measured by the dynamic technique during the exponential phase, for different operating conditions, finding a base condition which removes the limitation of oxygen. Also presents a dimensionless analysis of the variables and their correlation with experimental data. Maestría

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2001, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2001, Bu çalışmada fermentörlerin dizayn, simulasyon ve kontrolünün sağlanması amacıyla geliştirilmiş olan ilk fermentör dinamik matematik modeli ele alınarak irdelenmiş, belirli sitokiometik ve kinetik katsayıların model sonuçlarına olan etkileri araştırılmıştır. Matematik modelin mevcut bir bilgisayar programında çalıştırılmasıyla kullanılabilir bir araç elde edilmiş olmaktadır. Ayrıca bu çerçevede fermentasyon prosesi ile fermentör sistemlerinin özellikleri ve avantajları incelenmiştir. Matematik modeli oluşturan bileşenler, modele ait kabuller, model parametreleri, model sınırları ve temel kütle denge denklemleri verilmiştir. Matematik model kütle dengelerinden yola çıkılarak su sistemleri için geliştirilmiş bir bilgisayar programında çalıştırılmış, tam karışımlı bir fermentörün çıkış akımındaki VFA ve NH4-N konsantrasyonlarının çeşitli SRT ve HRT sürelerinde değişimleri belirlenmiş ve literatür datalarıyla karşılaştırılmıştır. Ayrıca çözünmüş KOI’yi oluşturan Css, Cmo, Ce gibi diğer değişkenlerinde fermentör çıkış akımındaki değerleri belirlenerek çözünmüş KOI oluşumuna ayrı ayrı olan katkıları araştırılmış ve modelde bu konudaki belirsizlik ortadan kaldırılmıştır. Fermentör çıkış akımındaki VFA ve NH4 konsantrasyonlarına çeşitli biyolojik kinetik ve stokiometrik katsayıların etkileri modelde “hassasiyet analizi” yapılarak belirlenmiştir., In this study, the first fermenter dynamic mathematical model developed to provide the design, simulation and control of the fermenters has been tackled and studied and the effects of certain stoichiometric and kinetic coefficients on the results of the model. With running the mathematical model in an existing computer program, a usable tool has been obtained. In addition, the fermentation process and characteristics and advantages of the fermenter systems have been investigated within this framework. The components constituting the mathematical model, assumptions belonging to the model, model parameters, model limits and basic mass balance equations have been given. Starting from the mass balances, the mathematical model was run in a computer program developed for the water systems, the changes of the concentrations of VFA and NH4-N in the effluent of a fermenter with a complete mixture have been determined at various SRT and HRT times and compared with the data in the literature. In addition, the values of the variables such as Css, Cmo, Ce forming the soluble COD in the fermenter effluent have been determined and their separate contributions to the soluble COD formation and the uncertainty in the model concerning this matter has been eliminated. The effects of the various biological kinetic and stoichiometric coefficients on the VFA and NH4 concentrations in the fermenter effluent have been determined by making a “sensitivity analysis” in the model., Yüksek Lisans, M.Sc.

Purple non-sulfur bacteria (PNSB) are phototrophic organisms that have raised interest for both industrial and domestic wastewater treatment and valorization because of their very high assimilation (~1 g CODX g-1 COD substrate) and valuable compounds production (i.e hydrogen, polyhydroxyalkanoates, pigments). PNSB have been studied mostly in pure- or co-cultures with fermentative bacteria. Mixed cultures have been little described. This work aims to enrich a stable association of fermenters and PNSB on a carbohydrate-rich wastewater in a single-step process with a mixed culture. Batches with glucose and acetate at different concentrations were inoculated with an in-house mixed-culture. A chemostat was continuously supplied with glucose (5 g COD L-1) and run at a dilution rate of 0.05 h-1 after start-up under batch mode and baseline stabilization of the PNSB enrichment with acetate. The reactor was constantly illuminated with a light filtered at wavelengths superior to 700 nm. Biomass, pigments expression and substrate depletion were tracked along the experiment. A model was developed to anticipate the biomass growth and the substrates consumption. In the batches fed with acetate, PNSB were dominant in purple biomass (>80% vs. total sequencing read count). The main PNSB population were Rhodopseudomonas and Rhodobacter. With glucose, the biomass turned white. The fermenter Enterobacter dominated the microbiomes (>95% abundance). In the stirred-tank reactor, batch operation with acetate led to the production of a substantial biomass enriched in PNSB (4.0 g VSS L-1) that assimilated the nutrients in a molar C-N-P ratio of 100:9.5:0.1 (- n/n/n). Under chemostat regime with glucose, PNSB were efficiently associated with fermenters in a biomass of 1.0-1.5 g VSS L-1. Phase-contrast microscopy displayed the typical morphotypes of Rhodopseudomonas and the fermenter Clostridium. The glucose was completely depleted. The main fermentation products were acetate (between 3 and 10 mmol L-1), ethanol (between 6 and 9 mmol L-1) and butyrate (between 2 and 4 mmol L-1). The hydrogen yield was low (0.033±0.012 mol H2 mol-1 glucose). A fermenters-PNSB mixed culture was successfully built by microbial community engineering by harnessing the chemostat regime to establish the ecological niches and interactions of these organisms. It provides an excellent opportunity to clean carbohydrate-rich wastewater in a compact single-stage process. In the case of direct application of PNSB, a concentrated biomass can be produced. The biomass can even find interesting applications for resource recovery in the form of, e.g., a protein-rich fertilizing biomass (on food and agricultural aqueous wastes), biogas, bulk chemicals and biopolymers.