O objetivo deste trabalho foi avaliar os efeitos de dois modificadores metabólicos, a sesamina, presente no óleo de gergelim, e ácido alfa-lipoico (na forma pura), sobre desempenho zootécnico, perfil de ácidos graxos, composição química dos filés de pacus e alterações histológicas no fígado. Foram utilizados 480 juvenis de pacu (3,35±0,78 g), distribuídos em 24 caixas de polietileno com volume de 50 litros, sendo estocados 20 peixes em cada unidade. Durante o período experimental de 90 dias, a temperatura média da água permaneceu em 26 °C e os demais parâmetros (amônia, nitrito, pH e oxigênio dissolvido) apresentaram-se dentro dos níveis adequados para o desenvolvimento desta espécie. O delineamento experimental foi inteiramente casualizado, no qual foram avaliados seis tratamentos em esquema fatorial 3x2, sendo três níveis do fator óleo (OS: óleo de soja; OG: óleo de gergelim; OL: óleo de linhaça) e dois níveis do fator ácido alfa-lipoico (AAL) (sem e com), resultando em seis tratamentos: T1: OS (controle); T2: OG+OL; T3: OL; T4: OS+AAL; T5: OG+OL+AAL e T6: OL+AAL. Os dados obtidos foram analisados estatisticamente por análise de variância (ANOVA) e diferenças significativas foram verificadas pelo teste de Tukey (5%). As dietas contendo OL como única fonte lipídica (T3 e T6) proporcionaram melhores índices de peso médio (PM) e ganho de peso individual (GPI) nos juvenis de pacu. Além disso, proporcionaram maiores (P<0,05) teores de ácidos graxos poli-insaturados (AGPI) da família n-3 nos filés, especialmente do ácido eicosapentaenoico (EPA, 20:5n-3). A única variável da composição química dos filés dos juvenis de pacu que apresentou diferença (P<0,05) foi o teor de proteína bruta, sendo maior nos filés dos peixes alimentados com as dietas sem ácido alfa-lipoico (T4, T5 e T6). Os óleos utilizados nas dietas experimentais não causaram alterações nas células dos fígados de juvenis de pacu. Conclui-se que a sesamina, fornecida por meio de óleo de gergelim, não promoveu alterações no desempenho zootécnico dos pacus, nem na composição química e metabolismo de ácidos graxos poli-insaturados (AGPI) dos filés de juvenis de pacu. A presença do ácido alfa-lipoico não afetou o desempenho zootécnico dos animais e sua ausência promoveu maiores teores de proteína bruta e ácidos graxos poli-insaturados nos filés dos pacus. / The objective of this work was to evaluate the effects of two metabolic modifiers, sesamin, present in sesame oil, and alpha lipoic acid (in pure form), on pacus growth performance, fatty acid profile, chemical composition of pacus fillets and histological alterations in the liver. We used 480 pacu juveniles (3.35±0.78 g), distributed in 24 boxes of polyethylene with volume of 50 liters, being stored 20 fish in each unit. During the experimental period of 90 days, the mean water temperature remained at 26 °C and the other parameters (ammonia, nitrite, pH and dissolved oxygen) were in the appropriate levels for the development of this species. The experimental design was completely randomized, in which six treatments were evaluated in a 3x2 factorial scheme, being three levels of the factor oil (OS: soybean oil, OG: sesame oil, OL: linseed oil) and two levels of the alpha acid factor -lipoic acid (AAL) (without and with), resulting in six treatments: T1: OS (control); T2: OG+OL; T3: OL; T4: OS+AAL; T5: OG+OL+AAL and T6: OL+AAL. Data were analyzed statistically by analysis of variance (ANOVA) and significant differences were verified by the Tukey test (5%). Diets containing OL as the only lipid source (T3 and T6) provided better average weight (PM) and individual weight gain (GPI) in pacu juveniles. In addition, they provided higher (P <0.05) levels of polyunsaturated fatty acids (PUFA) of the n-3 family in fillets, especially eicosapentaenoic acid (EPA, 20:5n-3). The only variable of the chemical composition of pacu juvenile fillets that presented a difference (P <0.05) was the crude protein content, being higher in the fish fillets fed the diets without alpha-lipoic acid (T4, T5 and T6). The oils used in the experimental diets did not cause changes in the livers cells of pacu juveniles. It was concluded that sesamin, provided by sesame oil, did not promote changes in the growth performance of pacus, nor in the chemical composition and metabolism of polyunsaturated fatty acids (PUFA) of pacu juvenile fillets. The presence of alpha-lipoic acid did not affect the animals growth performance and its absence promoted higher levels of crude protein and polyunsaturated fatty acids in pacus fillets.

O presente trabalho teve como objetivo estudar diferentes tecnologias na extração de óleo da semente de gergelim e de compostos fenólicos e proteínas da torta de gergelim. Este estudo está dividido em quatro partes. O objetivo da primeira parte do trabalho foi extrair compostos fenólicos de diferentes tortas de nozes e sementes nas mesmas condições e comparar o teor de tais compostos e a atividade antioxidante dos extratos. Nessa fase, foram utilizadas nos experimentos tortas das sementes de girassol, linhaça e gergelim, e das nozes amêndoa, pecã, macadâmia e avelã. O extrato da torta de noz pecã apresentou o maior teor de todos os compostos fenólicos analisados, seguido pelo extrato da torta de semente de girassol e de avelã. Essas amostras também apresentaram as maiores atividades antioxidantes. As etapas seguintes do trabalho focaram-se no gergelim. A segunda parte do trabalho teve como objetivo a otimização da extração, pela metodologia convencional, de fenólicos totais e lignanas da torta de gergelim. Inicialmente, um modelo polinomial de segunda ordem foi utilizado para predição dos resultados, mediante a variação da temperatura, concentração de etanol e razão, sólido/solvente. As variáveis de resposta foram as concentrações de fenólicos totais, de sesamina e de sesaminol triglicosídeo e a atividade antioxidante dos extratos obtidos. Entre os compostos analisados, o sesaminol triglicosídeo está presente em maior quantidade na torta de gergelim. A razão sólido/solvente e a concentração de etanol foram os fatores que mais afetaram a extração, enquanto a temperatura demonstrou uma influência reduzida. Na terceira etapa, o escopo da pesquisa foi a avaliação de metodologias alternativas na extração desses mesmos compostos e, também, de proteínas. As tecnologias usadas foram as de campo elétrico pulsado (CEP) e de descargas elétricas de alta tensão (DEAT). A análise da aplicação de CEP e de DEAT foi realizada usando essas tecnologias como pré-tratamentos ao processo de extração com solvente. Os resultados demonstraram que as técnicas foram eficazes e aumentaram os rendimentos do processo para fenólicos totais, lignanas e proteínas da torta. O uso de diferentes porcentagens de etanol também se mostrou significativo nessa etapa, entretanto, esse efeito foi reduzido quando utilizadas as tecnologias elétricas. Da mesma forma, o efeito da temperatura na etapa difusiva foi menor quando os pré-tratamento foram utilizados. Os comportamentos observados sugerem que a aplicação de CEP e DEAT aumenta a eficiência da extração de compostos de interesse. Por fim, na quarta parte do trabalho, objetivou-se melhorar a eficiência do processo de extração do óleo de gergelim aplicando as tecnologias previamente citadas. Esses experimentos demonstraram um efeito significativo dos tratamentos de CEP e DEAT e um aumento na quantidade de óleo extraído com o aumento da energia aplicada às sementes. O uso de DEAT gerou um aumento maior na quantidade de óleo extraído, se comparado à tecnologia de CEP. / The goal of the present work was to study different technologies in the extraction of oil from sesame seed and phenolic compounds and proteins from sesame cake. This study is divided in four parts. The first part aimed to extract water-soluble compounds from different seed and nut cakes under the same conditions and compare the phenolic content and antioxidant activity of the extracts. For the first portion of the study, seed cakes of sunflower, pumpkin, flaxseed and defatted sesame, and nut cakes of almond, pecan, macadamia and hazelnut were used in the experiments. The extract from pecan nut cake presented the highest amounts of all compounds analyzed, followed by sunflower seed and hazelnut cake extracts. These samples also had the highest antioxidant activities. The following steps of the work focused on sesame only. The second part of the work aimed to optimize the extraction of total phenolics and lignans from sesame seed cake. Initially, a second-order polynomial model was set up to predict the responses in different temperatures, solid/solvent ratios and ethanol concentrations. The response variables were the concentrations of total phenolics, sesamin, sesaminol triglucoside and antioxidant activity of the extracts. Among the analyzed compounds, ST is presented in the highest quantity in sesame cake. Solid to liquid ratio and ethanol concentration where the most important factors affecting extraction, whereas temperature showed reduced influence. In the third part of this work, the aim was to evaluate alternative methodologies in the extraction of phenolics and proteins. The technologies used were pulsed electric fields (PEF) and high voltage electric discharges (HVED). These methods were used as pre-treatments, prior to diffusion. Result show that PEF and HVED were efficient and increased the extraction yield for phenolic compounds, lignans and proteins from the cake. The use of different percentages of ethanol was also significant in this stage; however, the effect of this parameter was reduced when the electrical treatments were used. In the same way, temperature also showed a smaller influence on the results when the pre-treatments were used. The observed behaviors suggest that the use of PEF and HVED increases extraction efficiency. Finally, the goal of the last part of the work was to improve oil expression from sesame seeds, using the aforementioned technologies. These experiments show a significant effect of both PEF and HVED. It was observed an increase of the amount of oil extracted with the energy input applied to the seeds. When compared both technologies, HVED showed a more expressive effect then PEF.

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Το RDF (Resource Description Framework), πρότυπο του W3C, είναι ένα μοντέλο δεδομένων για την αναπαράσταση πληροφορίας στον Παγκόσμιο Ιστό και αποτελεί τη θεμελίωση ενός συνόλου τεχνολογιών για τη μοντελοποίηση κατανεμημένης γνώσης στο Σημαντικό Ιστό. Η παρούσα διπλωματική εργασία περιλαμβάνει τη μελέτη της τεχνολογίας RDF και της σημασιολογικής επέκτασης αυτής, του RDF Schema. Επίσης, στα πλαίσια αυτής της μελέτης έγινε συγκριτική αξιολόγηση των ήδη υπαρχόντων αρχιτεκτονικών για την αποθήκευση και επεξεργασία δεδομένων RDF, εκτιμώντας παράλληλα τη συμπεριφορά τους στην περίπτωση των κατανεμημένων αποθεμάτων. Επιπρόσθετα, αξιολογήθηκαν οι δυνατότητες που προσφέρει σε τέτοιους μηχανισμούς η γλώσσα SPARQL, μια γλώσσα επερωτήσεων για RDF η οποία αποτελεί πρότυπο του W3C. Τέλος, ερευνήθηκαν στο επίπεδο των κατανεμημένων αποθεμάτων δύο πολύ σημαντικά χαρακτηριστικά αυτής της τεχνολογίας, η δυνατότητα συνδυασμού των δεδομένων και της εξαγωγής συμπερασμάτων (inferencing) και η υποστασιοποίηση (reification). Στο τελευταίο στάδιο, και βάσει της παραπάνω αποτύπωσης, πραγματοποιήθηκε η ανάπτυξη μιας εφαρμογής σε γλώσσα Java, η οποία επιτρέπει τη σύνδεση σε ένα ή περισσότερα απομακρυσμένα ή και τοπικά αποθέματα RDF, διαθέτοντας τον απαραίτητο μηχανισμό αποστολής επερωτήσεων (queries) προς αυτά. Η συγκεκριμένη εφαρμογή επιτυγχάνει τον κατάλληλο συνδυασμό των διαθέσιμων κατανεμημένων πληροφοριών και την εξαγωγή συμπερασμών, μια διαδικασία που αποτελεί πρωταρχικό στόχο στο πεδίο του Σημαντικού Ιστού. Για την αξιολόγηση των χαρακτηριστικών της χρησιμοποιήθηκαν απλά παραδείγματα που επιβεβαιώνουν την ορθή λειτουργία της και φανερώνουν το εύρος των δυνατοτήτων της. Άλλωστε, η επεκτασιμότητα και η αξιοπιστία ενός τέτοιου μηχανισμού αποτέλεσαν τη φιλοσοφία πάνω στην οποία στηρίχθηκε η ανάπτυξη του, λαμβάνοντας συγχρόνως υπόψη τα ιδιαίτερα χαρακτηριστικά των κατανεμημένων αποθεμάτων εγγράφων RDF. / RDF (Resource Description Framework), a W3C recommendation, is a data model for representing information in the World Wide Web and constitutes the foundation of many existent technologies for the modeling of distributed knowledge in the Semantic Web. This thesis includes a study of the RDF technology and of its semantic extension, RDF Schema. Also, a comparative evaluation was made among already existing frameworks for the storage and management of RDF data, appreciating their behavior in the case of distributed repositories. Moreover, an evaluation was made for the possibilities that SPARQL offers in such mechanisms, a RDF query language and soon a W3C recommendation. Finally, two very important characteristics of this technology were researched in the field of distributed repositories, the possibility of combination of data and export of conclusions (inferencing) and reification. In the last part, and based on the above imprints, an application was developed in Java, which allows the connection to one or more remote and local RDF repositories, having the necessary mechanism as well for making queries. This application successfully combines distributed knowledge and leads to inferencing, something that is a fundamental objective in the field of Semantic Web. For the evaluation of this application's characteristics, simple examples were used that confirm its proper function and reveal the breadth of its possibilities. Scalability and reliability have been the main goals during this application's development phase, having always in mind that we refer to distributed RDF repositories, which are more complicated and have some special characteristics.

The aim of this study was to determine the rheological properties of tahin/pekmez blends at different tahin concentrations (20-32%) and temperatures (35-65 &deg / C) by using a concentric cylinder rotational viscometer. Samples were sheared with seven different rotational speeds at an increasing order. The shear rates (0.75-63.9 s-1) were calculated by the Power-law Approximation method. Tahin/pekmez blends were found to exhibit non-Newtonian, shear thinning behavior at all temperatures and tahin concentrations. The experimental data of apparent viscosity versus shear rate were successfully described by the Power-law model. The model parameters / flow behavior index, n varied in the range of 0.7-0.85, whereas the values for the consistency coefficient, K, were in the range of 282-2547 mPa.sn. Apparent viscosity and consistency coefficient of blends increased with increasing tahin concentration and decreasing temperature. Temperature dependency of K was described by an Arrhenius-type equation. Activation energies (Ea) of the blends appeared in the range of 13376-28592 J/mol as the tahin concentration was increased from 20% to 32%. The effect of temperature on n was found to be significant but did not follow any descriptive trend. The relationship between K and tahin concentration was explained by exponential and power functions while tahin concentration had no significant effect on flow behavior index. Power function was found to be superior in explaining the variation of Ea with tahin concentration. A mathematical model was formulated to determine the combined effect of temperature, tahin concentration and shear rate on apparent viscosity.

In this study, new methods and processing equipments for sesame dehulling were investigated. First, water absorption of sesame seed was studied at 20, 30, and 40&deg / C. The data could be modeled using Peleg equation where it was found that the constant k1 was inversely related to temperature but the effect of temperature on k2 was negligible. In the second phase of the work a lab scale continuous screw conveyor as dehuller and two equipments, (1) fluidized bed dryer and (2) hull separator to function as agitator, dryer and separator, for hull separation were designed. Fluidized bed unit was unsuccessful as it caused rapid drying of seeds before hulls can be removed. Using designed dehuller and hull separator, seeds at 30.5, 50.4 and 70.7 % db moisture contents were processed at dehuller speeds of 420, 840, and 1150 rpm. It was found that the percentage of dehulled seeds was linearly dependent on moisture content, optimal speed of designed dehuller was 840 rpm, and results for the efficiency of dehulling the seeds were significantly the same at 420 and 1150 rpm. Repeated passes of seeds through dehuller not only increased the efficiency of dehulling but also the percentage of damaged seeds. A dehulling efficiency of about 92.5 % was attained after four passes. The possibility of soaking seeds in an enzyme solution before dehulling was also investigated. By this means, after soaking in 0.2 % (v/v) Peelzyme-I solution for 15 min, a dehulling efficiency of 95 % was achieved.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 6 uppsatser.

Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 4 uppsatser.

Espumas à base de amido possuem limitações para utilização como embalagens na indústria alimentícia, principalmente, devido à alta hidrofilicidade e fragilidade. Para melhorar essas propriedades, torna-se necessário o uso de plastificantes e outros aditivos, como proteínas e fibras lignocelulósicas, ou ainda um aditivo fonte desses recursos, como a torta de gergelim obtida como resíduo do processamento do gergelim. Sendo assim, o objetivo deste trabalho foi desenvolver e caracterizar espumas à base de amido de mandioca adicionadas de 0 – 40 % (m/m) de resíduo de gergelim, produzidas pelo processo de expansão térmica, a fim de avaliar a influência do aditivo nas propriedades físicas, morfológicas e mecânicas dos materiais obtidos para utilização como embalagens para alimentos. A adição do resíduo resultou em espumas com menores espessuras e densidade aparente, bem como, maior capacidade de expansão dos materiais. Além disso, apresentaram melhores propriedades mecânicas e, em geral, menores capacidade de absorção de água e adsorção de água em baixas umidades relativas, em relação aos materiais compostos somente por amido. Embora as propriedades mecânicas das espumas sejam influenciadas pelas condições de umidade relativa de armazenamento, as espumas contendo 20 % de resíduo (20R) apresentaram uma combinação de propriedades no ensaio de tração (resistência à tração e módulo de elasticidade) que podem ser consideradas comparáveis às amostras de bandejas comercias de poliestireno expandido (EPS), nas três umidades relativas avaliadas (33, 53 e 90 %). Os resultados obtidos nos ensaios de flexão dessas espumas indicaram que as mesmas foram mais rígidas e menos flexíveis do que as amostras de EPS. A adição de 20 % de resíduo resultou em importantes melhorias nas propriedades físicas e mecânicas em comparação às espumas à base de amido de mandioca, além de apresentarem menos defeitos morfológicos do que os observados em espumas com maiores teores do resíduo (30 e 40 %). Foram realizados testes de aplicação das espumas 20R no acondicionamento de dois tipos de alimentos com diferentes teores de umidade: bolo (23 %) e brócolis (91 %), em comparação ao armazenamento em embalagens comerciais de EPS. A partir dos resultados obtidos para a variação de umidade, perda de massa e propriedades mecânicas na flexão das embalagens, foi observado que as espumas propostas não foram adequadas para o acondicionamento das amostras de brócolis, apresentando alta absorção de umidade e deformações após três dias de contato com o alimento. Por outro lado, as espumas 20R mostraram bom desempenho no acondicionamento das amostras de bolo, não apresentando mudanças significativas nas propriedades mecânicas no período de 3 a 9 dias de armazenamento. Dessa forma, o resíduo de gergelim em combinação com o amido de mandioca mostrou elevado potencial para o desenvolvimento de espumas que podem ser utilizadas como embalagens para alimentos com baixos teores de umidade, sendo necessários estudos mais detalhados, considerando principalmente aspectos de segurança para utilização de resíduos em produtos em contato direto com alimentos. / Starch based foams have limitations for use as food packaging, mainly due to high hydrophilicity and fragility. In order to improve these properties it is necessary the use of plasticizers and others additives, such as lignocellulosic fibers and proteins, or an additive source of these constituents like sesame cake, which it is obtained from sesame processing. In this way, the main objective of this work was to develop and characterize starch based foams added with 0 – 40 % (w/w) of sesame residue to evaluate the influence of this additive on physical, morphological and mechanical properties of materials for using as food packaging. The foams were produce by thermal expansion process. Residue addition resulted in foams with smaller thickness and density, as well as greater expansion capacity of the materials produced. In addition, foams incorporated with residue exhibited better mechanical properties and, in general, lower water capacity absorption and water adsorption at low relative humidities compared to foams made only with starch. Although mechanical properties of the foams are affected by storage humidity conditions, foams added with 20 % of residue (20R) showed tensile properties (tensile strength and tensile elasticity modulus) that can be considered comparable to expanded polystyrene (EPS) commercial trays for different relative humidities evaluated (33, 53 and 90 %). Flexural properties indicated that starch foams produced was tougher and less flexible than EPS commercial trays. Addition of 20 % of sesame residue on cassava starch-based foams resulted in relevant improvements compared to foams without residue. Besides that, fewer morphological defects were noted, as observed in foams with higher residue content (30 and 40 %). Thus, 20R formulation was selected to carrying out applicability tests of starch-based foams in packaging of two types of food with different moisture content: cake (23 %) and broccoli (91 %) compared to EPS commercial packaging. From the results obtained for moisture variation, loss of weight and flexural properties of the foams, it was found that the material proposed was not applicable to package broccoli samples. Due to high water absorption by the foams alterations on the shape were noted in the materials after 3 days in contact with this food. Nonetheless, foams based on cassava starch and 20 % of sesame residue exhibited a good performance during storage time of cake samples (9 days). It was not observed any effect on flexural mechanical properties for 3 to 9 days of storage. Thereby, sesame cake added to cassava starch showed high potential to developing foams that could be used as packaging for low moisture food. Additionally, more detailed studies are necessary, especially considering safety aspects mainly for using agricultural residues directly in contact with food products.

Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-05-17T19:54:36Z No. of bitstreams: 1 ALÉCIO RODRIGUES PEREIRA – DISSERTAÇÃO (PPGMET) 2016.pdf: 1473036 bytes, checksum: f4065590dec1a06792fec3cb161284c1 (MD5) / Made available in DSpace on 2018-05-17T19:54:36Z (GMT). No. of bitstreams: 1 ALÉCIO RODRIGUES PEREIRA – DISSERTAÇÃO (PPGMET) 2016.pdf: 1473036 bytes, checksum: f4065590dec1a06792fec3cb161284c1 (MD5) Previous issue date: 2016-04-13 / CNPq / O experimento foi realizado na Chapada do Apodi, a oeste do Rio Grande do Norte, na estação experimental da EMPARN - Empresa de Pesquisa Agropecuária do Rio Grande do Norte, localizada no município de Apodi -RN. O objetivo da pesquisa foi determinar as necessidades hídricas do gergelim irrigado (Sesamum indicum L.), cultivar BRS ANAHÍ. Foi conduzido durante a estação seca do ano de 2015, entre os meses de agosto, setembro e outubro. Uma torre micrometeorológica instalada na área de cultivo abrigou os seguintes instrumentos para determinação dos componentes do balanço de energia: um saldo radiômetro, dois piranômetros, dois psicrômetros, dois fluxímetros, dois anemômetros e um datalogger. Na estimativa da necessidade hídrica da cultura foi empregado o método do balanço de energia baseado na razão de Bowen (BREB). A evapotranspiração da cultura (ETc) e o coeficiente de cultivo (Kc) foram obtidas para as condições climáticas da Chapada do Apodi. A evapotranspiração de referência (ET0) foi estimada pelo método de Penman-Monteith utilizando os dados meteorológicos, obtidos na estação automática do INMET, em Apodi-RN. Os resultados evidenciam que, em relação ao saldo de radiação (Rn), os fluxos de calor latente (LE), calor sensível (H) e calor no solo (G) corresponderam a 81,3%, 17,7% e 0,4%, respectivamente. Com a evolução da cobertura do solo pela cultura a fração do saldo de radiação utilizada como fluxo de calor latente aumentou, enquanto que aquela utilizada como fluxo de calor sensível diminuiu. A ETc acumulada ao longo da estação de cultivo foi de 566,2 mm, correspondendo a uma média de 6,9 mm dia-1. A Fase III (desenvolvimento reprodutivo da cultura) apresentou maior demanda hídrica, com média de 8,0 mm dia-1. Os valores do Kc foram: 0,6 no estágio inicial, 0,9 no estágio médio e 0,8 no estágio final. O valor do Kc médio determinado experimentalmente foi inferior àquele recomendado pela FAO-56 nas Fases: I (emergência), II (desenvolvimento vegetativo) e III (desenvolvimento reprodutivo), enquanto que na Fase IV (frutificação e maturação) foi superior. / The experiment was conducted in the Apodi Chapada, west of Rio Grande do Norte, in experimental station EMPARN - Agricultural Research Company of Rio Grande do Norte, Located in the municipality of Apodi -RN. The objective of the research was to determine the water requirements of irrigated sesame (Sesamum indicum L.), grow crops BRS ANAHÍ. It was conducted during the dry season 2015 year, between the months of August, September and October. A micrometeorological tower installed in the growing area housed the following instruments for the determination of the components of energy balance: a net radiometer, two pyranometer two psychrometers, two soil heat flux plates, two anemometers and one datalogger. In estimating the water requirement of the crop was used the Bowen Ratio energy balance method (BREB). The crop evapotranspiration (ETc) and the crop coefficient (Kc) were obtained for the climatic conditions of Apodi Chapada. The reference evapotranspiration (ET0) was estimated by the Penman-Monteith method using meteorological data, obtained in the weather station of INMET, in Apodi-RN. The results show that, compared to net radiation (Rn), the latent heat flux (LE), sensible heat (H), and soil heat flux (G) corresponds to 81.3%, 17.7% and 0.4%, respectively. With the evolution of the soil covered by the crop the fraction of net radiation used as latent heat flux increased, while the one used as sensible heat flux decreased. A ETc accumulated during the growing season was 566.2 mm, corresponding to an average of 6.9 mm day-1. Phase III (reproductive development of culture) showed higher water demand, with 8.0 mm day-1. The values Kc were: 0.6 at the initial stage, 0.9 in the middle stage and 0.8 in the final stage. The value of the average determined experimentally Kc It was lower than that recommended by the FAO-56 in phases: I (emergency), II (vegetative growth) and III (reproductive development) while Stage IV (fruit set and ripening) was higher.