Milhões de toneladas de resíduos são gerados pela agroindústria todos os anos, gerando problemas ambientais e econômicos; muitos destes resíduos, entretanto, são ricos em nutrientes e compostos funcionais, o que poderia tornálos subprodutos com valor agregado. A utilização de subprodutos possibilita enriquecimento dos alimentos processados, redução de descarte no meio ambiente e melhor aproveitamento dos recursos naturais. Os talos de beterraba são um exemplo de resíduo com potencial a ser explorado e, assim como os bulbos, são ricos em betalaína, composto responsável pela sua coloração vermelho-violeta. Esses pigmentos são aplicáveis na indústria alimentícia como corantes naturais, mas a sua estabilidade é um dos maiores desafios frente a sua utilização. Neste contexto, este trabalho tem como objetivo principal estudar a extração, a clarificação e a estabilização de betalaínas provenientes de talos de beterraba vermelha. Para tanto, foi inicialmente estudado a viabilidade da utilização dos talos de beterraba como fonte de betalaínas e, em sequência, a extração destes compostos via esmagamento. A utilização de diferentes processamentos com vistas à melhora da extração e o seu impacto na estabilidade das betalaínas presente no extrato foram investigados: o processamento por alta pressão (HPP do inglês High Pressure Processing) e o tratamento térmico com alta temperatura por curto tempo (HTST do inglês High Temperature Short Time). Por fim, foi realizado um estudo de clarificação do extrato por meio de processo de separação por membranas (PSM). A clarificação foi aplicada por microfiltração (MF) seguido por ultrafiltração (UF). Além disto, a MF também foi operada no modo diafiltração (DF). A redução da atividade da enzima peroxidase, as características físico-químicas, a cor e a taxa de degradação das betalaínas ao longo do armazenamento foram avaliados nos extratos antes e após a clarificação. Os resultados mostraram que os extratos obtidos via esmagamento possuíam em média 45% da quantidade de pigmentos presentes no extrato dos bulbos de beterraba. O processamento por HPP não foi considerado uma boa alternativa para melhorar a extração e também não contribuiu para o aumento na estabilidade dos pigmentos presentes nos extratos. O tratamento térmico HTST causou uma pequena degradação das betalaínas; porém, quando aplicado por 120 s a 85,7 °C nos extratos com alta concentração inicial, promoveu uma redução na taxa de degradação das betalaínas da amostra tratada de 1,2 para 0,4 mg de betanina/100 ml de extrato por dia após uma semana de armazenamento. No estudo de clarificação por PSM, os experimentos de MF e UF apresentaram reduções no fluxo do permeado ao longo do processo, além de elevada tendência ao fouling, em ambas as membranas. A aplicação da MF batelada seguida por UF ocasionou uma redução de 99,5% da atividade de peroxidase. Quando a MF foi operada em modo DF, a alimentação do processo foi modificada de duas bateladas de 2 L cada para uma batelada de 3 L, aproveitando melhor os pigmentos da alimentação. Além disto, a clarificação contribuiu para a estabilidade das betalaínas, uma vez que a taxa de degradação reduziu de 0,32 e 0,41 mg de betanina/100 ml de extrato por dia para 0,2 mg de betanina/100 ml de extrato por dia no 10° dia de armazenamento. Os processos de MF, em modo batelada e DF, seguidos por UF promoveram redução na turbidez e no teor de sólidos solúveis, além de extratos clarificados com cor mais intensa, luminosa e avermelhada. / Every year a huge amount of waste is generated by agricultural industry, becoming a serious environmental and economic problem; many of these wastes, however, contain nutrients and functional compounds, which could make them by-products with added value. The use of by-products allows the enrichment of processed foods and the reduction of discard in the environment, ensuring a better use of natural resources. The beet stalks are an example of waste with potential to be explored and, as the root, are rich in betalains, whose provide their red-violet color. These pigments are applicable in the food industry as natural dyes. The stability of these pigments, however, is one of the biggest challenges of using it. In this context, this work aims to study the extraction and clarification of betalains from red beet stalks. Initially it was studied the feasibility of using beet stalks like a betalain source and, after that, the extraction of these compounds through crushing was carried out. The utilization of different processing to improve the extraction and the impact on the betalain stability present in the extract were studied: the high pressure processing (HPP) and the thermal treatment high temperature short time (HTST). Lastly, a study of clarification of the extract using the membrane separation processes (PSM) was carried out. Clarification was first applied by microfiltration (MF) followed by ultrafiltration (UF). In addition, MF was also operated in diafiltration mode (DF). The peroxidase activity reduction, physico-chemical characteristics, color and degradation rate of betalains over the storage were evaluated in the extracts before and after the clarification. The results show that the stalks extract by crushing had about 45% of the pigments content in the extract from root of beet. HPP was not considered a suitable alternative to improve the extraction and did not contribute to the increase in the stability of the pigments present in the extracts. The thermal treatment HTST caused a small degradation of betalains. However, when it was applied for 120 s at 85.7 °C, in the extracts with high initial concentration, it promoted a reduction in the betalain degradation rate of the treated sample from 1.2 to 0.4 mg of betanin/100 ml of extract per day after one week of storage. In the PSM clarification study, the MF and UF experiments, showed permeated flux reduction, indicating high fouling tendency on both MF and UF membranes. The application of MF followed by UF caused a reduction of 99.5% in peroxidase activity. When MF was operated in DF mode, the process feed was modified from two batches of 2 L each to a 3 L batch, making better use of feed pigments. In addition, the clarification experiments contributed to the betalain stability, as the betalain degradation rate reduced from 0.32 and 41 mg of betanin/100 ml of extract per day to 0.2 mg of betanin/100 ml of extract per day on the 10th day of storage. The MF processes, batch and DF mode, followed by UF promoted a reduction in the turbidity and soluble solids content and the clarified extracts had color more intense, bright and reddish.

The sugar beet (Beta vulgaris) plant has in recent years been added to the Biofuel Industrial Strategy (Department of Minerals and Energy, 2007) by the South African government as a crop grown for the production of bio-ethanol. Sugar beet is commonly grown in Europe for the production of sucrose and has recently been cultivated in Cradock and the surrounding areas (Engineering News, 2008). The biofuel industry usually ferments the sucrose with Saccharomyces cerevisiae to yield bio-ethanol. However, researchers are presented with a critical role to increase current yields as there are concerns over the process costs from industrial biotechnologists. The beet factories produce a pulp by-product removed of all sucrose. The hemicellulose-rich pulp can be degraded by microbial enzymes to simple sugars that can be subsequently fermented to bio-ethanol. Thus, the pulp represents a potential source for second generation biofuel. The process of utilising microbial hemicellulases requires an initial chemical pre-treatment step to delignify the sugar beet pulp (SBP). An alkaline pre-treatment with ‘slake lime’ (calcium hydroxide) was investigated using a 23 factorial design and the factors examined were: lime load; temperature and time. The analysed results showed the highest release of reducing sugars at the pre-treatment conditions of: 0.4 g lime / g SBP; 40°C and 36 hours. A partial characterisation of the Clostridium cellulovorans hemicellulases was carried out to verify the optimal activity conditions stated in literature. The highest release of reducing sugars was measured at pH 6.5 – 7.0 and at 45°C for arabinofuranosidase A (ArfA); at pH 5.5 and 40°C for mannanase A (ManA) and pH 5.0 – 6.0 and 45°C for xylanase A (XynA). Temperature studies showed that a complete loss of enzymatic activity occurred after 11 hours for ManA; and 84-96 hours for ArfA. XynA was still active after 120 hours. The optimised lime pre-treated SBP was subsequently degraded using various combinations and percentages of C. cellulovorans ArfA, ManA and XynA to determine the maximal release of reducing sugars. Synergistically, the highest synergy was observed at 75% ArfA and 25% ManA, with a specific activity of 2.9 μmol/min/g protein. However, the highest release of sugars was observed at 4.2 μmol/min/g protein at 100% ArfA. This study has initiated the research within South Africa on SBP and its degradation by C. cellulovorans. Preliminary studies show that SBP has the potential to be utilised as a second generation biofuel source.

In my diploma thesis I am analysing world sugar market and the role of the Czech Republic on this market. In the first chapter I am describing sugar as a general commodity, its usage, consumption and production, also the production in important areas. In the second part of the thesis I am writing about the restrictions of the sugar market from European Union, I am describing all reforms and quotas and its influence on all countries. In the third part, the most important one, I am writing about sugar trade on Exchange which instruments are mainly being used, news forms of trading such as Fair Trade. I am also describing factors that influence development of prices. In the last part, also very important one, I am writing about the role of the Czech Republic on the world market and its development throughout the years and about attenuation of the sugar production in our country.

<p>Истраживања из овира овог рада обухватила су испитивање тока ферментације подлога на бази екстракционог, ретког и густог сока као међупроизвода, и меласе као нуспроизвода технологије прераде шећерне репе квасцем <em>Saccharomyces cerevisae.</em> Експериментално је потврђена изводљивост добијања етанола дисконтинуалном ферментацијом екстракционог, ретког и густог сока као и меласе из домаћих фабрика шећера&nbsp;квасцем Saccharomyces cerevisae у биореактору радне запремине 1,5 l.</p><p>Анализом резултата тока ферментације међупроизвода технологије прераде шећерне репе дефинисани су параметри значајни за моделовање применом поступка одзивне површине функције. За опис одзивних функција броја ћелија квасца, садржаја етанола и укупног садржаја шећера током ферментације испитан је утицај почетног садржаја шећера у опсегу 5-25 % m/v и трајања ферментације у опсегу 0-48 h. Добијени модели допринели су бољем разумевању утицаја различитог почетног садржаја шећера, трајања ферментације и међусобнихи интеракција ових фактора на одабране одзиве тока ферментације хранљивих подлога на бази међупроизвода технологије прераде шећерне репе.</p><p>Поред наведеног, циљ овог рада обухватио је и дефинисање оптималних вредности почетног садржаја шећера и трајања ферментације екстракционог, ретког и густог сока као међупроизвода и меласе као нуспроизвода технологије прераде шећерне репе, применом методе жељене функције у комбинацији са полиномским зависностима посматраних одзива. За екстракциони сок оптималне вредности варираних параметара, при којим жељена функција има највећу вредност су почетни садржај шећера 12,71 % m/v и трајање ферментације 38 h. Дефинисане оптималне вредности варираних параметара за густи сок су почетни садржај шећера 12,75 % m/v и трајање ферментације 42&nbsp;h. За меласу су дефинисане следеће оптималне вредности варираних параметара: почетни садржај шећера 11,59&nbsp;% m/v &nbsp;и трајање ферментације 34&nbsp;h.</p><p>Наставак истраживања је изведен са циљем провере валидности добијених резултата, односно њихове применљивости у увећаним размерама. Добијени резултати тока ферментације у биореактору радне запремине 10 l, при оптималним условима дефинисаним за ферментацију у биореактору радне запремине 1,5&nbsp;l су у доброј корелацији са вредностима оптимизованих одзива које су предвиђене моделима.</p> / <p>Istraživanja iz ovira ovog rada obuhvatila su ispitivanje toka fermentacije podloga na bazi ekstrakcionog, retkog i gustog soka kao međuproizvoda, i melase kao nusproizvoda tehnologije prerade šećerne repe kvascem <em>Saccharomyces cerevisae.</em> Eksperimentalno je potvrđena izvodljivost dobijanja etanola diskontinualnom fermentacijom ekstrakcionog, retkog i gustog soka kao i melase iz domaćih fabrika šećera&nbsp;kvascem Saccharomyces cerevisae u bioreaktoru radne zapremine 1,5 l.</p><p>Analizom rezultata toka fermentacije međuproizvoda tehnologije prerade šećerne repe definisani su parametri značajni za modelovanje primenom postupka odzivne površine funkcije. Za opis odzivnih funkcija broja ćelija kvasca, sadržaja etanola i ukupnog sadržaja šećera tokom fermentacije ispitan je uticaj početnog sadržaja šećera u opsegu 5-25 % m/v i trajanja fermentacije u opsegu 0-48 h. Dobijeni modeli doprineli su boljem razumevanju uticaja različitog početnog sadržaja šećera, trajanja fermentacije i međusobnihi interakcija ovih faktora na odabrane odzive toka fermentacije hranljivih podloga na bazi međuproizvoda tehnologije prerade šećerne repe.</p><p>Pored navedenog, cilj ovog rada obuhvatio je i definisanje optimalnih vrednosti početnog sadržaja šećera i trajanja fermentacije ekstrakcionog, retkog i gustog soka kao međuproizvoda i melase kao nusproizvoda tehnologije prerade šećerne repe, primenom metode željene funkcije u kombinaciji sa polinomskim zavisnostima posmatranih odziva. Za ekstrakcioni sok optimalne vrednosti variranih parametara, pri kojim željena funkcija ima najveću vrednost su početni sadržaj šećera 12,71 % m/v i trajanje fermentacije 38 h. Definisane optimalne vrednosti variranih parametara za gusti sok su početni sadržaj šećera 12,75 % m/v i trajanje fermentacije 42&nbsp;h. Za melasu su definisane sledeće optimalne vrednosti variranih parametara: početni sadržaj šećera 11,59&nbsp;% m/v &nbsp;i trajanje fermentacije 34&nbsp;h.</p><p>Nastavak istraživanja je izveden sa ciljem provere validnosti dobijenih rezultata, odnosno njihove primenljivosti u uvećanim razmerama. Dobijeni rezultati toka fermentacije u bioreaktoru radne zapremine 10 l, pri optimalnim uslovima definisanim za fermentaciju u bioreaktoru radne zapremine 1,5&nbsp;l su u dobroj korelaciji sa vrednostima optimizovanih odziva koje su predviđene modelima.</p> / <p>Research from the framework of this study included the examination of the course of fermentation based on raw, thin and thick juice as intermediate products, and molasses as by-products of sugar beet proccessing by yeast <em>Saccharomyces cerevisiae</em>. The feasibility of ethanol production from raw, thin and thick juice and molasses from local sugar factories was experimentally confirmed in batch fermentation in a bioreactor of working volume 1.5 l. lmportant parameters for modeling of the process using response surface methodology were defined by analyzing the results of the course of fermentation of intermediate products of sugar beet processing. For description of the response function of the number of yeast cells, ethanol content and total sugar content during fermentation, the effects of initial sugar content in the range 5-25% w/v and duration of fermentation in the range 0-4g h were examined. Obtained models have contributed to a better understanding of the impact of different initial sugar content, fermentation time and interactions of these factors on the selected responses of the course of fermentation of culture media based on intermediate products of sugar beet processing.</p><p>ln addition, the goal of this work included the selection of the optimal values of the initial sugar content and duration of fermentation of raw, thin and thick juice and molasses applying the obtained second-degree polynomial models of the process. Optimal initial sugar content and fermentation time for ethanol production from raw juice were estimated to be 72.71% w/v and 38 h, respectively. For thin juice optimal values of varied parameters were the initial sugar content 12.75% w/v and fermentation time 42 h. The optimal values of initial sugar content and fermentation time for thick juice were defined to be 21,12% w/v and 47 h, respectively. For molasses were defined the following optimal values of varying parameters: the initial sugar content 11,59% w/v and fermentation time 34 h.<br />Further research was performed with the aim of validation of the obtained results and confirmation of their applicability in the enlarged scale. The results obtained during the fermentation in bioreactor of working volume 10 l, under optimal conditions defined for fermentation in the bioreactor of working volume 1.5 l, were in good correlation.</p>

Subsurface drainage has recently become common for agriculturally productive soils and key to maintain and improve crop production in poorly drained, frigid clay soils. The first study was conducted for four years (2014-17) at Casselton, ND to determine best combination of drainage, tillage and crop rotation for higher corn yield. Our finding suggested corn yield was highest with no drainage, CS and CH combination in years with drought conditions. The second study was conducted for three years (2015-17) to evaluate subsurface drainage spacing (9, 12, and 15m) and depth (0.9 and 1.2m) combination on corn, soybean and sugarbeet yields and residual soil nitrate-nitrogen (NO3-N) contents. Results indicated that 9 m drain spacing produced highest corn and soybean yield when average across three years in contrast with drain depth that has no effect on corn and soybean yield except for sugarbeet where the 1.2m depth yielded higher than the 0.9m depth. / North Dakota Corn Council / North Dakota Soybean Council / North Dakota Water Resources Research Institute

Leafy spurge (Euphorbia esula L.) is a costly noxious weed to manage in the Northern Great Plains; it invades rangelands and displaces native and desirable vegetation. Our first objective was to test the recommended full rate and half rate of selected herbicides applied in September following a spring burn on a leafy spurge invaded plant community. Our second objective was to determine if raffinate (desugared beet molasses) applied to leafy spurge invaded rangeland would attract cattle to consume leafy spurge. The aminocyclopyrachlor with chlorosulfuron treatment had the best leafy spurge control at the full rate, with stem density reductions of 95 percent for both sites nine and twelve months after treatment. The salt block treatment had the best success at reducing leafy spurge stem density. Herbicides can be the most common and effective type of management; however, manipulating livestock to graze noxious weeds converts a weed into a useable forage.

Orientador: Francisco Luiz Araújo Câmara / Banca: Carlos Armênio Khatounian / Banca: Roberto Lyra Villas Bôas / Resumo: Com o objetivo de avaliar o efeito dos adubos orgânicos, em cultivos sucessivos de chicória e beterraba, foi instalado um experimento na Chácara São João, em Botucatu - SP. O delineamento experimental usado, foi de blocos ao acaso com 16 tratamentos, sendo combinações de quatro tipos de adubação e quatro dosagens, caracterizando um esquema fatorial 4 x 4, com quatro repetições. Os tratamentos usados foram composto orgânico, composto biodinâmico, compostagem laminar com esterco e compostagem laminar com Bokashi, todos a 0, 90, 180 e 270 kg N.ha-1. As parcelas foram constituídas de três fileiras de chicória (primeiro cultivo), e três fileiras de beterraba (segundo cultivo), com dois metros de comprimento. O espaçamento entre plantas foi de 30 cm para chicória, totalizando 18 plantas por parcela, e de 15 cm para beterraba, totalizando 36 plantas por parcela. Foram feitas análises de solo antes da instalação do experimento, após colheita da chicória e após colheita da beterraba, e análise dos teores de minerais (N, P, K, Ca, Mg) presentes na chicória e na beterraba. Em todos os tratamentos a chicória e beterraba apresentaram desenvolvimento adequado. O solo, inicialmente com teor adequado de nutrientes, pode ter influenciado a resposta das adubações efetuadas, fazendo com que todas as formas e doses utilizadas neste trabalho, inclusive a dose zero, se mostrassem satisfatórias no suprimento nutricional da chicória e da beterraba. / Abstract: The objective was to evaluate the effect of organic fertilizers, in successive cultivations of chicory and red beet. Two experiments were installed at Chácara São João, in Botucatu - SP. Ramdomized blocks were used for the experimental design with 16 treatments, by combinations of four types of fertilizers at four levels, characterizing a factorial scheme 4 x 4, with four replications. The treatments were organic compost, biodynamic compost, laminate compost with cattle manure and laminate compost with Bokashi, all of them 0, 90, 180 e 270 kg N.ha-1. The experimental units consisted of three rows of chicory (first cultivation), and three rows of red beet (second cultivation), with two meters length. The space among the plants was 30 cm for chicory, with 18 plants per plot, and 15 cm for red beet, with 36 plants per plot. Analysis of the soil were made before the installation of the experiment, after the harvest of the chicory and after the harvest of the red beet, and analysis of the amount of minerals (N, P, K, Ca, Mg) present in chicory and red beet. In all treatments chicory and red beet showed adequate development. The original level of nutrients in the soil, resulted in absence of response at any form and dosis of fertilizers, including zero level. So, all treatments resulted enough in the nutritional demands of Cichorium endivia and Beta vulgaris. / Mestre

O presente trabalho teve como objetivo avaliar os aspectos fisiológicos, bioquímicos e microbiológicos de beterrabas Early Wonder minimamente processadas e inteiras submetidas a tratamentos pós-colheita. Para os tratamentos, os seguintes produtos foram aplicados: etileno (1000µL L-1), 1-MCP (300nL L-1) e ácido salicílico (500mg L-1), além do controle sem tratamento. Após os tratamentos, o produto foi armazenado a 5oC durante 10 dias. Observou-se que o ácido salicílico, promoveu a diminuição nos teores de sólidos solúveis, pH e na taxa respiratória de beterrabas minimamente processadas. Além disso, verificou-se que a fisiologia de beterraba minimamente processada é diferente de beterraba inteira, que foi comprovada ao analisar a taxa respiratória e a produção de etileno, as quais foram significativamente maiores no produto minimamente processado. As contagens de bactérias psicrotróficas e coliformes totais, para beterraba minimamente processada mantiveram-se dentro dos limites aceitáveis durante 10 dias de armazenamento. Não foi detectada presença de coliformes a 45ºC e Salmonella. Ficou evidenciada a eficiência do armazenamento a 5ºC no controle da atividade metabólica e segurança de beterrabas minimamente processadas. As injúrias causadas durante o processamento mínimo induziram o aumento na atividade da fenilalanina amônia-liase. Entretanto, a aplicação de ácido salicílico diminuiu a atividade desta enzima. Os tratamentos aplicados nas beterrabas minimamente processadas e inteiras pouco influenciaram na concentração de betalaínas e de fenóis totais. Verificou-se que, em tecidos de beterrabas Early wonder, não houve qualquer indício de adstringência provocada por tanino. / The purpose of the present work was to evaluate physiological, biochemical and, microbiological aspects of Early Wonder whole and minimally processed beet roots submitted to different treatments. The following treatments were applied: ethylene (1000µL L-1), 1-MCP (300nL L-1) and, salicylic acid (500mg L-1). After treatments, beet roots were stored at 5oC during 10 days. It was observed that salicylic acid promoted decrease of soluble solids, pH and, respiratory rates of minimally processed beet roots. It was also noted differences between whole and minimally processed beet roots physiology. This difference was observed by the high values of respiratory and ethylene production rates in the minimally processed beet roots. Psychrotrophic bacteria and total coliforms count for minimally processed beet roots were within acceptable limits for 10 days of storage. The presence of coliforms at 45ºC and Salmonella was not detected. Storage at 5ºC was effective to control the metabolic activity and to keep food safety of minimally processed beet roots. The injuries occurred during the minimal processing induced the increase of phenylalanine ammonia-lyase activity. However, the use of salicylic acid decreased the activity of this enzyme. The treatments applied on whole and minimally processed beet roots have little influence on betalains and total phenol concentration. It was not detected astringency on beet roots Early wonder tissues.

Os objetivos deste trabalho foram determinar respostas fisiológicas, bioquímicas e microbiológicas associadas ao processamento mínimo de beterraba e desenvolver um fluxograma de preparo específico para está hortaliça, visando menor perda de qualidade e máxima capacidade de conservação. No primeiro experimento foram estudados alguns aspectos fisiológicos de beterraba intactas, descascadas e raladas e aspectos microbiológicos de beterrabas raladas. Neste experimento foram realizadas análises da taxa respiratória, da produção de etileno e microbiológicas. No segundo experimento foi testado o efeito do ácido cítrico sobre a respiração e pigmentos de betalaínas, determinando-se a taxa respiratória e os teores de betalaínas. No terceiro experimento avaliou-se o tempo de sanitização para beterrabas minimamente processadas, sendo realizadas análises sensoriais, microbiológicas e físico-químicas. No quarto experimento foi estudado o momento de sanitização ideal para beterrabas minimamente processadas, sendo também efetuadas análises sensorias, microbiológicas e físico-químicas. E no quinto experimento foi testado o novo fluxograma de preparo, específico para beterrabas minimamente processadas através de métodos combinados, obtidos a partir de resultados dos testes anteriores. Análises sensoriais, microbiológicas e físico-químicas foram realizadas para avaliar o novo fluxograma. A taxa respiratória foi maior para beterrabas raladas. A produção de etileno somente foi detectada em beterrabas raladas. Os resultados das análises microbiológicas estão de acordo com o padrão vigente atualmente. O ácido cítrico reduziu a atividade respiratória e o extravazamento e a degradação dos pigmentos de betalaínas em beterrabas minimamente processadas. O tempo de sanitização de 3 minutos é mais apropridado para manutenção da qualidade. A sanitização apenas após a pelagem é a mais apropriada para manutenção da qualidade, pois reduz a perda de pigmentos e garante um produto com padrões microbiológicos abaixo dos limites permitidos pela Legislação Brasileira, além de evitar o desperdício de cloro. Verificou-se pelo novo fluxograma de preparo que as beterrabas minimamente processadas tem um período de comercialização viável por 10 dias. O novo fluxograma desenvolvido é mais indicado para manutenção da qualidade por reduzir perda de pigmentos, reduzir a taxa respiratória e garantir a segurança alimentar do produto. / The purposes of this work were to determine the physiological, biochemical and microbiological responses to minimal processing of beet roots and to develop a preparation flowchart for this vegetable, aiming at lowering quality losses and maximizing preservation. Some physiological aspects of whole, peeled and grated beet roots, as well as microbiological aspects of grated beet roots were studied in the first experiment. Analyses of respiratory rate, ethylene production and microbiology were carried out in this experiment. In the second experiment, respiratory rates and betalain amounts were determined to evaluate the effects of citric acid on respiration and betalain pigments. In a third experiment, the sanitization time for minimally processed beet roots was evaluated and sensory, microbiological and physicochemical analyses were carried out. In a fourth experiment, the ideal sanitization time for minimally processed beet roots was determined and sensory, microbiological and physicochemical analyses were carried out. In a fifth experiment, a specific new procedures flowchart was tested for the minimal processing of beet roots using a combination of methods based on previous experiments. Sensory, microbiological and physicochemical analyses were conducted to evaluate the new procedures flowchart. The respiratory rate was higher in grated beet root. Ethylene production was detected only in grated beet roots. The microbiological results were in accordance with the current standard. Citric acid reduced the respiratory activity, betalain exudation and degradation in minimally processed beet roots. A three-minute sanitization showed to be the most suitable for quality maintenance. Sanitization alone after pealing is appropriate for quality maintenance, as it decreases pigment losses, prevents wasteful use of chlorine and ensures microbiological standards to be in accordance with the Brazilian Legislation. Minimally processed beet root produced by the new procedures flowchart are suitable for commercialization for 10 days. The new procedures flowchart is especially recommended for quality maintenance, once it decreases pigment loss and the respiratory rate, and ensures good food-safety standards for the product.

Intégrée dans une unité de production de sucre et d'éthanol, la digestion anaérobie peut fournir une solution écologique pour traiter la matière organique tout en fournissant l'énergie qui peut, en partie, couvrir les besoins énergétiques de l'usine. L’objet de cette thèse de doctorat est la compréhension et l’optimisation de la méthanisation des coproduits de sucrerie et de distillerie de betterave dans l’optique d’une intégration industrielle du procédé. D’une part, la faisabilité de la digestion des pulpes en mono-substrat et sans dilution en réacteur parfaitement agité a été démontrée. La digestion thermophile s’est révélée efficace et stable jusqu’à une charge organique comprise entre 5 et 5,9 kg MO/m3.j. La biodégradabilité des pulpes est élevée, le taux d’abattement de matière organique de 88,1% et la production spécifique de méthane de 0,353 Nm3 CH4/kg MO. Des contraintes technologiques spécifiques aux pulpes, comme par exemple les phénomènes de moussage ou d’abrasion des pompes, ont été mises en évidence.D’autre part, la méthanisation des vinasses en conditions mésophiles a révélé les limites du procédé parfaitement agité. La charge maximale, autour de 3 kg DCO/m3.j, a permis d’obtenir une production spécifique de méthane de 0,353 Nm3 CH4/kg MO mais l’accumulation de sels d’acides gras volatils, y compris à faible charge organique, indique un déséquilibre entre les flores acidogène et méthanogène. D’un point de vue biologique, il semble que c’est la concentration élevée en sels des vinasses (C=31,7 mS/cm et [K]=14 g/L), qui représenterait le frein principal au développement et à l’activité des microorganismes. L’utilisation du modèle AM2, qui distingue deux phases, acidogénèse et méthanogénèse, a mis en évidence un faible taux de croissance spécifique des archées méthanogènes. L’extraction partielle des sels par électrodialyse a permis de lever une partie de cette inhibition, tandis que leur dilution a permis, à charge organique équivalente, de diminuer le temps de séjour d’un facteur 4 sans altérer les performances de la méthanisation, ceci en diminuant les concentrations en acétate et propionate dans le digesteur. Pour permettre l’intensification du procédé, le recyclage des microorganismes dans le digesteur a été étudié et a permis d’atteindre une charge organique de 6 à 7 kg DCO/m3.j. Enfin, la caractérisation des digestats de méthanisation a permis d’envisager leurs différentes voies de traitement (évapoconcentration, séparation solide/liquide,…) et de vérifier leurs caractéristiques agronomiques.En perspective, Cristal Union envisage la construction d’un démonstrateur permettant de tester différentes configurations à l’échelle industrielle. Le traitement successif des coproduits selon leur disponibilité, les pulpes en campagne sucrière, puis les vinasses en intercampagne, est envisagé. Les phases de transition entre ces deux périodes ont été étudiées et la faisabilité d’une alimentation mixte, sans réduction de la charge, démontrée. Dans cette optique, notre choix se porterait sur des conditions de température mésophiles, plus favorables au traitement d’un produit tel que les vinasses. Un système de recyclage de la biomasse est alors indispensable. / The growing international demand for energy and water constitutes a significant challenge for modern industry. Integrated in a sugar and ethanol factory, anaerobic digestion can provide an environmentally friendly solution by using organic matter co-products to provide energy that can partially cover the factory’s needs. The purpose of this doctoral thesis is the study of the anaerobic digestion of sugar beet pulps and distillery vinasses. We used a multiscale approach to achieve the two main objectives: understanding the biological phenomena involved and analyzing the technological problems that can occur in the digesters. We first demonstrated the feasibility of the anaerobic digestion of beet pulps in a continuously stirred tank reactor (CSTR) without water addition. Thermophilic digestion was effective and we achieved a high degradation of pulps with satisfactory biogas yields. The thermophilic process could operate stably up to an organic loading rate of 5 to 5,9 kg VS.m-3.d-1. The biodegradability of pulps was very high and allowed to obtain a VS destruction of 88,1% with a specific methane production of 0,353 Nm3 CH4.kg-1 VS. Next, the mesophilic anaerobic digestion of vinasses revealed the limits of the CSTR process for the treatment of this high strength distillery wastewater. The maximum loading rate reached was between 2 and 3 kg COD.m-3.d-1, with a specific methane production of 0,344 Nm3 CH4.kg-1 VS. However, the accumulation of volatile fatty acid salts, even at low organic loading rates, indicated an imbalance between acidogenic and methanogenic microflora. From a biological perspective, we assumed that the high salt concentration of vinasses (up to 41,3 mS/cm) is the main obstacle to the development and activity of microorganisms, as a two-reaction model (AM2) showed low specific growth rate of methanogens. The partial extraction of salts by electrodialysis allowed to remove a part of this inhibition, while their dilution led, at equivalent organic loading rate, to the reduction of the residence time by a factor 4. This was achieved without decreasing methane yield, while also reducing concentrations of acetate and propionate in the digester. To enable process intensification, biomass recycling in the digester, after the centrifugation, was tested to compensate for their low specific growth rates; loading rates reached 7 kg COD.m-3.d-1. We subsequently put in place a strategy for digesters control, to ensure effective monitoring. Finally, we had to characterize the digestates and to consider their different treatment paths. (evapoconcentration, solid / liquid separation, ...) before final valorization. For the industrial scale up, we envisage the successive treatment of the coproducts according to their availability: pulps during the sugar campaign and then vinasses in the intercampaign. As such, we also studied the transition periods and demonstrated the feasibility of a mixed feed, without reducing the loading rate. For such a project, we would choose mesophilic temperature conditions, more favorable for the treatment of a product like vinasses. A system for biomass recycling, whose efficiency was demonstrated, must be installed when the vinasses are treated. The system needs to be compatible with the treatment of the two substrates proposed, for example centrifugation or filtration.