Artigos Científicos - ITEC

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/3360

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Acesso aberto (Open Access)
Simulation of machine learning-based 6G systems in virtual worlds
(International Telecommunication Union, 2021) OLIVEIRA, Ailton Pinto de; NASCIMENTO, Arthur Matheus do; COSTA, Walter Tadeu Neves Frazão da; TRINDADE, Isabela Pamplona; BASTOS, Felipe Henrique Bastos e; GOMES, Diego de Azevedo; MÜLLER, Francisco Carlos Bentes Frey; KLAUTAU JÚNIOR, Aldebaro Barreto da Rocha
Digital representations of the real world are being used in many applications, such as augmented reality. 6G systems will not only support use cases that rely on virtual worlds but also benefit from their rich contextual information to improve performance and reduce communication overhead. This paper focuses on the simulation of 6G systems that rely on a 3D representation of the environment, as captured by cameras and other sensors. We present new strategies for obtaining paired MIMO channels and multimodal data. We also discuss trade-offs between speed and accuracy when generating channels via ray tracing. We finally provide beam selection simulation results to assess the proposed methodology.
Acesso aberto (Open Access)
Comparison of the effects of brazil nut oil and soybean oil on the cardiometabolic parameters of patients with metabolic syndrome: a randomized trial
(Multidisciplinary Digital Publishing Institute, 2020) SILVA, Lívia Martins Costa e; MELO, Maria Luisa Pereira de; REIS, Fernando Vinícius Faro; MONTEIRO, Marta Chagas; SANTOS, Sávio Monteiro dos; GOMES, Bruno Alexandre Quadros; SILVA, Luiza Helena Meller da
Recent evidence suggests that replacing saturated fat with unsaturated fat is beneficial for cardiovascular health. This study compared the effects of Brazil nut oil (BNO) and soybean oil (SO) supplementation for 30 days on anthropometric, blood pressure, biochemical, and oxidative parameters in patients with metabolic syndrome (MS). Thirty-one patients with MS were randomly allocated to receive 30 sachets with 10 mL each of either BNO (n = 15) or SO (n = 16) for daily supplementation. Variables were measured at the beginning of the study and after 30 days of intervention. No change in anthropometric and blood pressure variables were observed (p > 0.05). Total (p = 0.0253) and low-density lipoprotein (p = 0.0437) cholesterol increased in the SO group. High-density lipoprotein cholesterol decreased (p = 0.0087) and triglycerides increased (p = 0.0045) in the BNO group. Malondialdehyde levels decreased in the BNO group (p = 0.0296) and total antioxidant capacity improved in the SO group (p = 0.0110). Although the addition of oils without lifestyle interventions did not affect anthropometric findings or blood pressure and promoted undesirable results in the lipid profile in both groups, daily supplementation of BNO for 30 days decreased lipid peroxidation, contributing to oxidative stress reduction.
Acesso aberto (Open Access)
Fracture modes of AISI type 302 stainless steel under metastable plastic deformation
(Associação Brasileira de Metalurgia e Materiais, 2017-11) SANTOS, Jheison Lopes dos; MONTEIRO, Sergio Neves; CÂNDIDO, Veronica Scarpini; SILVA, Anderson Oliveira da; RAMOS, Flávio James Humberto Tommasini Vieira
Martensitic transformation can be induced by plastic deformation in metastable iron-based alloys, such as stainless steels containing limited amounts of C, Ni and Cr. This transformation takes place at the temperature range from Ms and Md, usually at relatively lower temperature values. The transformed martensite has been associated with maximum ultimate strength and relatively high ductility. In the present work, the tensile fracture characteristics of a metastable AISI type 302 stainless steel was properties were compared to those of a stable AISI type 310 austenitic stainless steel. It was found that in 302 steel, its high degree of metastability and dilute dispersion of inclusions result in higher strength and complex modes of fracture, one of which consisting of martensite surrounding globular inclusions.
Acesso aberto (Open Access)
Análise da influência do formato de elemento de concreto e propriedades de fibras de aço na tenacidade à flexão
(Rede Latino-Americana de Materiais, 2018-10) OLIVEIRA, Marco Antonio Barbosa de; RAMOS, Edson Marcos Leal Soares; OLIVEIRA, Dênio Ramam Carvalho de; POMPEU NETO, Bernardo Borges
Concrete characterizing studies with steel fibers starting from the assay of the traction on flexural of prisms to obtain the toughness flexural have being done to the parameterization of the mechanic behavior of concrete pipes with steel fibers. The study aim is to adjust curves modeling the toughness estimates to the flex on concrete pipes in function to the toughness flexural on prims, both with steel fibers randomly oriented and moreover verify if there is or there is not significant statistic difference among toughness average to flexural when compared to the concrete element form (pipe or prism), and the priorities of steel fibers: Form Factor (65 or 80), State (free or joined to the basis comb) and theoretical fiber consumptions (0,25% or 0,38% or 0,50%). Curves were adjusted modeling the concrete pipe toughness with steel fibers in function of prism flexural toughness, being possible to observe that larger is the prism flexural toughness the larger will be the pipe flexural toughness. The analysis of variance was used to evaluate the existence or not of significant statistic difference among double or triple or quadruples associations. It was individually found that there is not significant statistic difference among the average values of toughness flexural, when compared concrete elements forms, however, there is significant statistic average values of toughness flexural when compared: (i) Form Factor; (ii) State and (iii) Theoretical Fiber Consumption. There was influence on the average values of flexural toughness when we make associations among the different levels of form factors, state and theoretical consumptions on fibers.
Acesso aberto (Open Access)
Avaliação do comportamento reológica e mecânico de geopolímero sintetizado com reaproveitamento de resíduo
(Rede Latino-Americana de Materiais, 2018-10) BRITO, Woshington da Silva; BRUM, Sebastião Martins; SILVA, André Luis Mileo Ferraioli; FELIPE, Augusta Maria Paulain Ferreira; SOUZA, José Antônio da Silva
The sustainable construction of the future, besides low energy consumption and greenhouse gas emissions must also adopt the principle of reusing wastes generated by the production chain that impact the environment. One of the most impacting wastes generated by the aluminum production chain is fly ash. Geopolymers are cementitious materials with a three-dimensional structure formed by chemical activation of aluminosilicates. According to studies some ashes have proven to be suitable sources of Al and Si for the geopolymerization reaction. One of the most important aspects in the commercializing these products is their behavior in a plastic state. The workability of fresh geopolymer paste can be measured using several common tests used for Portland cement concrete, such as flow and slump; however, a more in-depth characterization of their rheology is essential for understanding their basic setting mechanisms. The objective of this work was to evaluate the rheological behavior of the Davidovits (SiO2/Al2O3) geopolymer paste at 2.65; 3.04 and 4.11. The mechanical resistance to compression at 24 hours, 7 days and 28 days of geopolymer cure was also evaluated. The geopolymerization reaction was conducted at ambient temperature of 28°C and 15 Molar sodium hydroxide (NaOH) and 10 Molar sodium silicate (Na2SiO3), were used as the activator. Fly ash and metakaolin were used as source of Al and Si was used. XRD, XRF, SEM techniques were used in the characterization of raw materials and geopolymers. The geopolymer with a lower Davidovits ratio of 2.65 presented better workability in its fresh state and higher mechanical strength at 40.80 MPa compression with 28 days cure at ambient temperature. The Herchel Bulkley rheological model was the one that was best adjusted to the geopolymers.
Acesso aberto (Open Access)
Corrosão em estacas metálicas de torres de energia elétrica
(Rede Latino-Americana de Materiais, 2019-05) VILHENA, Alexandre Evangelista Rodrigues; PINTO, Renata Godinho; COSTA, Rafaela Reis da; PICANÇO, Marcelo de Souza; MACÊDO, Alcebíades Negrão
In order to maintain the quality and continuity of the power supply it is essential to monitor the integrity of the structure of the transmission towers usually executed in steel. This study evaluated soil corrosivity in the Amazon region in the Vila do Conde-Tucuruí stretch, state of Pará. The resistivity, potential soil structure, redox potential, pH, chloride, sulphate and sulfate concentration, besides the Steinrath index and the quantification of the soil corrosivity through the installation of test specimens in the studied soil. The data were collected in the dry and rainy period while the specimens were removed after 12 months of exposure. The soils of the region presented resistivity higher than 20 kΩ.cm, characterizing as few corrosives; the redox potential of 100 to 300 mV indicated mild to moderately corrosive soils; the potential soil structure remained in the range of -0.4 to -0.7 V/ECS being within the range considered normal; the Steinrath index classified the soils into little corrosive to non-corrosive and the corrosion rates of the test specimens indicated high corrosion at 3 meters depth. Based on the results of each evaluation method used it can be verified that the soil corrosivity increases with the depth, besides being favorable to the attack of microbiological corrosion.
Acesso aberto (Open Access)
Dependência de recursos e custos de transação: rumo a um modelo convergente
(Universidade Federal do Pará, 2017-12) LOPES, Arleson Eduardo Monte Palma
The present study addresses the process of inter-organizational relationships from two theoretical perspectives: resource dependence and transaction costs. First, the text presents a bibliographic review on the two theoretical constructs; next, it discusses how the use of these theories can contribute to understanding the interorganizational phenomenon. Despite the divergence between the two perspectives, the authors conclude that they are convergent based on the bibliographic review. The convergence of these conceptions relates to the fact that organizational relations are a key factor for the functioning of companies. The resource dependence perspective suggests that resources are distributed in the environment and that firms develop organizational relationships to obtain them; in contrast, the perspective of transaction costs refers to the relations of economic exchange between organizations. Therefore, it is necessary to consider the assumptions of these two theoretical perspectives to understand inter-organizational relationships
Acesso aberto (Open Access)
Identificação de patologias em fachadas e metodologia de análise: estudos de casos na Universidade Federal do Pará
(Universidade Federal do Pará, 2014-10) CARVALHO, Isabella Chaves; PICANÇO, Marcelo de Souza; MACÊDO, Alcebíades Negrão
The system of external cladding of the building acts as a protective layer and contributes to the proper aspect. The facade is subject to the action of agents of degradation as one of the most exposed areas of the building, with the presence of pathology becoming responsible for high repair costs. Research suggests as a goal, a survey on of buildings facades in the Federal University of Pará, to acquire grants to run future interventions in public facilities from the identification of the main problems present in the case studies. Started the development of evaluation methods to identify the damage with a standardized manner from the document production that facilitate visual inspections with obtaining information from damage. From the result of the identification of pathologies in facades with their respective methods of analysis, was expected to contribute to the increase in procedures that seek technical and economic performance of façades as a whole, assisting in future maintenance of the buildings in question, as well as production of reference source for other ventures.
Acesso aberto (Open Access)
Aforar, arrumar e alinhar: a atuação da Câmara Municipal de Belém na configuração urbano-fundiária da cidade durante o século XIX
(Universidade Federal do Pará, 2018-12-03) LIMA, José Júlio Ferreira; FISCHER, Luly Rodrigues da Cunha; ABREU, Paula Vanessa Luz de
The paper examines the morphological transformation of the city of Belém, influenced by the new land regime inaugurated by the Land Law of 1850 and by the growth of state urban planning. We investigate the actions of the City Council in the urban land tenure and the implementation of an Expansion Plan for Belém in the 19th century. In order to understand the spatial actions undertaken by the City Council, we started from the study of three instruments: emphyteusis, the main form of land transfer used by the City Council; alignment, related to the public-private boundaries and streets definitions; and land demarcation. We investigated the original land documents that record the emphyteusis, alignment and land demarcation carried out by the City Council along the Bragança Road, the main axis of city expansion in the 19th century. From the graphic spatialization of the information contained in these documents and the research in local newspapers, it was possible to verify that the City Council acted as a pioneer state agent, through a systematized land subdivision project. The discussion contributes to the comprehension of the structuring role of the local power in the definition and change of urban morphology and to a new understanding of the Belém Expansion Plan, classifying it as not only a urban beautification project, but as a product of the political-land tenure transition that marks the nineteenth century.
Acesso aberto (Open Access)
Ornamentos de platibanda em edificações de Belém entre os séculos XIX e XX: inventário e conservação
(Universidade Federal do Pará, 2017-12) ARRUDA, Tainá Chermont; SANJAD, Thais Alessandra Bastos Caminha
The vitrified ceramic ornaments were used as decorative elements and pieces such as statues, had allegorical paper in the crowning of the facades to highlight or to characterize the typological function of the building or as a symbol that the owner wanted to convey referring to the values defended at the time of the Industrial Revolution. The ornaments on the platibands formed a set of pieces with allegorical meanings, which symbolized wealth and erudition, to be attributed to the elite, since the Modern era. The objective of this research was to identify the ornaments made of glazed ceramic that make up the eclectic architecture of the Historic Center of Belém (Pará) and its surroundings with a view to tracing subsidies for its preservation. We sought to identify and locate the types of vitrified ornaments existing in the Historic Center and its surroundings of the city of Belém do Pará, through a visual inspection of the region, making it possible to analyze and understand the context of these pieces in the local reality. A total of 225 properties with ornamental plaice were identified in the analyzed area. The use of textual documents, printed catalogs, newspapers and albums of the 19th and 20th century was used to support research and identification of ornaments. Vitrified ceramic ornaments suffer an accelerated process of disappearance because they are exposed in the building panels, since they are more vulnerable to intemperate action, be it physical, chemical or mineralogical, and anthropic action, including acts of vandalism. These glazed ceramic ornaments are important examples of the cultural heritage of Belém, as they are evidence of the European influence in the region, more specifically Portuguese, besides being products of technical development of the material and symbolic of the nineteenth century, which deserve urgent preservation actions.
Acesso aberto (Open Access)
Lime-based restoration paints: characterization and evaluation of formulations using a native species from the Amazon flora and PVA-based glue as additives
(Universidade Federal do Pará, 2017-09) SILVA, Mayra Martins; SANJAD, Thais Alessandra Bastos Caminha; COSTA, Marcondes Lima da; COSTA, Solange do Perpétuo Socorro Evangelista
Based on historic documents, two lime-based paint formulations were produced in laboratory in order to evaluate their basic characteristics as restoration materials for historic buildings with lime-based components. The paints were made basically with hydrated lime, clay, water and linseed (Linum usitatissimum L.) oil, and one formulation had PVA (polyvinyl acetate)-based glue as fixative, and the other one, Couma guianensis' latex. Each paint component was characterized by XRD and FTIR, and color and specular gloss measurements were performed on both paints. A preliminary assessment of the paints was conducted using the Pipe Method, the salt crystallization test, visual analysis for dustiness, and analysis of microbiological growth. The results showed that the laboratory-produced paints are theoretically and technologically compatible with lime-based coatings, however, their superficial performance can be improved to achieve greater durability. This study also brings to light local materials from the Amazon region that have great potential to be used and recognized as raw materials for paints and which could also be investigated for other uses.
Acesso aberto (Open Access)
Construction delays: a case study in the Brazilian Amazon
(Universidade Federal do Pará, 2017-09) MAUÉS, Luiz Mauricio Furtado; SANTANA, Wylliam Bessa; SANTOS, Paulo Cerqueira dos; NEVES, Renato Martins das; DUARTE, André Augusto Azevedo Montenegro
The construction industry is one of the industrial sectors with the lowest rates of fulfilment of contract deadlines, especially in developing countries. This fact has been the focus of considerable discussions seeking to identify the causes of the delays. The main purpose of this paper is to use factor analysis to identify the factors that are correlated with delay, contemplating exclusively residential real estate projects and using a city in the Brazilian Amazon as a case study. Based on the database from the government agency that authorises constructions in the city of Belém (City Planning Department - Secretaria Municipal de Urbanismo, SEURB) and data from construction companies, the study investigated 274 construction projects from the past 11 years. Factor analysis and work with the variables that can be identified and measured in the initial phase of the project, i.e., during the feasibility study, demonstrate that the physical characteristics of the apartments and the construction project are the primary causes for variations in construction delays; these causes have not yet been reported in the literature. We hope that the results of this study will contribute to more consistent forecasting of construction time, minimising the risk of delays.
Acesso aberto (Open Access)
Effect of the T6 Heat Treatment on Microhardness of a Directionally Solidified Aluminum-Based 319 Alloy
(Universidade Federal do Pará, 2017-11) MAGNO, Igor Alexsander Barbosa; SOUZA, Fabricio Vinicius Andrade de; BARROS, André dos Santos; COSTA, Marlo Oliveira; NASCIMENTO, Jacson Malcher; COSTA, Thiago Antônio Paixão de Sousa; ROCHA, Otávio Fernandes Lima da
Aluminum alloys of the ANSI series 319 present Si and Cu as the main alloying elements and the mechanical strength of these alloys can be improved by the precipitation of the metastable Al2Cu phase during the ageing heat treatment. In this paper, the Al-5.5wt.%Si-3wt.%Cu alloy was elaborated and solidified in a water-cooled horizontal directional solidification device. The as-cast ingot was subjected to the precipitation hardening heat treatment (T6 heat treatment), which consisted of: solution for 5 h at 490°C±2°C, followed by quenching in water at 60°C±2°C and ageing for 3 h at 155°C±2°C, and cooling-air. Secondary dendrite arm spacing (λ2) measurements were carried out before and after T6 heat treatment. The mechanical strength of the alloy was investigated by the microhardness test. It has been found that the heat treatment did not influence the λ2 values, however, highest HV values have been observed for the heat-treated samples.
Acesso aberto (Open Access)
Tubos de concreto produzidos com fibras de aço e agregados da região metropolitana de Belém do Pará
(Universidade Federal do Pará, 2017-12) OLIVEIRA, Marco Antonio Barbosa de; MACÊDO, Alcebíades Negrão; POMPEU NETO, Bernardo Borges; CABRAL, Antonio Eduardo Bezerra
Reinforced steel-fiber concrete pipes emerge as an interesting technological variant. In an incipient study of the locality, the main objective was to assess the technical feasibility of discontinued reinforced steel-fiber concrete pipes randomly oriented by the diametrical compression test for mechanical behaviour analysis. The second objective was to verify the water absorption and effective fiber content in the spigot, barrel and bell of the tube. In this study, DRAMIX 80/60 or 65/35 steel fibers were used (loose or glued) in the theoretical contents of 0.25%, 0.38% and 0.50%. The results indicated that the concrete pipes from the TCFA 80/60 - FCP series in the effective fiber contents of 0.36% and 0.50% and the TCFA 80/60 - FS series in all effective contents were the only ones that reached the minimum failure loading and post-cracking established by the NBR 8900 (ABNT, 2007). The water absorption results were below the maximum absorption recommended by NBR 8900 (ABNT, 2007) and there were higher levels of absorption and effective fiber content in the chain from the order spigot, barrel and bell. Finally, the technical feasibility of reinforced steel-fiber concrete pipes in the locality was shown to be timely.
Acesso aberto (Open Access)
Avaliação de processos de misturas de concretos com agregados graúdos reciclados
(Universidade Federal do Pará, 2017-09) CORDEIRO, Luciana de Nazaré Pinheiro; MASUERO, Ângela Borges; DAL MOLIN, Denise Carpena Coitinho; SOUZA, Paulo Sérgio Lima; PAES, Isaura Nazaré Lobato
The reuse of construction waste is a strategy employed to achieve sustainability, however, only a small number of construction initiatives use it. The variability of concrete residue is an inherent condition of this product and it must be considered. The control of the production process of concrete produced with concrete waste can improve the quality of the final composite. This paper aims to evaluate the effect of the mixing process and the mixer type on the fragility of recycled coarse aggregate concrete and to investigate their influence on compressive strength. This study also evaluates the effect of the mixer on concrete performance. Recycled coarse aggregate concrete was used as a total replacement for natural coarse aggregate. The results showed no significant differences between concrete produced from different types of mixtures, however, both yielded satisfactory compressive strength results at 28 days. However, the mixtures made in the vertical shaft mixer were more efficient than the mixtures produced in the inclined axis mixer, as the concrete produced by the former presented a lower variation coefficient. The study concluded that the equipment's characteristics contributed to better uniformity, leading to less variability in the resulting concrete.
Acesso aberto (Open Access)
Elaboration and characterization of snack bars made with ingredients from the Amazon
(Instituto Nacional de Pesquisas da Amazônia, 2017-06) PRAZERES, Isadora Cordeiro dos; DOMINGUES, Alessandra Ferraiolo Nogueira; CAMPOS, Ana Paula Rocha; CARVALHO, Ana Vânia
Snack bars were launched on the market as an alternative for people seeking healthier food options. They are popular portable snacks commonly eaten between meals. This study aimed to develop snack bars made with tapioca flour, Brazil nut and native fruit pulps (açaí, cupuaçu, muruci and taperebá) as well as to assess their physical, physicochemical, microbiological and sensory attributes. The preferred concentration of fruit pulp was 10% in the açaí bar, and 15% in the cupuaçu, muruci and taperebá bars. The acceptance rate of the açaí bars was greater than 70% for the attributes appearance, color, texture, and overall impression, but was lower for flavour. This result may be related to the eating habits of some panelists, who eat açaí pulp without adding any other ingredients that can impart the unique flavour of the fruit. The cupuaçu and muruci snack bars had higher sensory acceptance than the açaí and taperebá bars; therefore, they are more likely to have better market prospects.
Acesso aberto (Open Access)
Canaã dos Carajás: um laboratório sobre as circunstâncias da urbanização, na periferia global e no alvorecer do século XXI
(Associação Nacional de Pós-Graduação e Pesquisa em Planejamento Urbano e Regional, 2018-04) CARDOSO, Ana Cláudia Duarte; CÂNDIDO, Lucas Souto; MELO, Ana Carolina Campos de
This article addresses the processes of urbanization and urban sprawl in Canaã dos Carajás, a small relatively recent Amazonian municipality. The analysis is dialectically structured according to Lefebvre’s interpretation of the levels of social reality. The global level captures how capitalintensive activities (mining, ranching, and monoculture) have impacted the connection between the place of production and the global market. The mixed level explains how local social groups, inspired by global processes, have mediated urbanization. The local level demonstrates how blind spots in understanding the ongoing processes have impaired the strengthening of diversity, and led to the exclusion of social groups that most depend on the land and nature. We conclude that it is necessary to articulate contemporary formulations and studies on Brazilian urbanization so as to demonstrate the selective manner in which modernization takes place and is constituted in new forms of colonization, whenever economic opportunities formulate socioenvironmental issues in a conservative manner.
Acesso aberto (Open Access)
Diversity of yeasts during fermentation of cocoa from two sites in the Brazilian Amazon
(Instituto Nacional de Pesquisas da Amazônia, 2019-03) ALMEIDA, Silvana de Fátima Oliveira de; SILVA, Letícia Ribeiro Carvalho; GHAGAS JUNIOR, Gilson Celso Albuquerque; OLIVEIRA, Guilherme; SILVA, Silvia Helena Marques da; VASCONCELOS JUNIOR, Santelmo Selmo de Vasconcelos; LOPES, Alessandra Santos
The purpose of this study was to identify the yeasts involved in spontaneous fermentation of cocoa from the Brazilian Amazon region. The fermentation process was carried out experimentally with cocoa seeds from two sites (Medicilândia and Tucumã), State of Pará, northern Brazil, during a six-day period. Totals of 44 yeasts were isolated from Medicilândia and 29 from Tucumã. Molecular identification was carried out by sequencing the D1/D2 region fragment of the rRNA 26S gene, expanded with universal primers for the NL1GC and LS2 eukaryotes. Pichia manshurica and Saccharomyces cerevisiae were identified in Medicilândia and five yeast species (Pichia fermentans, P. kudriavzevii, P. manshurica, S. cerevisiae and Zygosaccharomyces bailii) were identified in Tucumã. The results showed that P. manshurica and S. cerevisiae may have potential for use as starter cultures in future studies to improve the quality of cocoa seeds fermented in the Brazilian Amazon region.
Acesso aberto (Open Access)
Comparative study on the quality of oil extracted from two tucumã varieties using supercritical carbon dioxide
(Universidade Federal do Pará, 2016-06) COSTA, Bárbara Elizabeth Teixeira; SANTOS, Orquídea Vasconcelos dos; CORRÊA, Nádia Cristina Fernandes; FRANÇA, Luiz Ferreira de
The vast Amazon region has considerable territorial peculiarities and plant species diversity, sometimes from the same botanical family, which can exhibit significant differences in physicochemical properties. From this diversity, two species stand out – Amazonas tucumã (Astrocaryum aculeatum Meyer) and Pará tucumã (Astrocaryum vulgare Mart.). The research focus is to analyze, comparatively, these oleaginous fruits, their similarities, particularities and potentials regarding the oil quality extracted from two tucumã varieties from the states of Amazonas and Pará, obtained using supercritical carbon dioxide, under different extraction parameters. The results demonstrate the biometric particularities of each species, highlighting the Amazon fruit, which also showed higher oil yield using supercritical CO2 extraction. The fatty acid quality and profile aspects of the oils show their unsaturated predominance, considering carotenoid content and how the extraction temperature can influence the nutritional quality of the oils. The statistical analyses indicated that the Amazon tucumã oil is superior to the Pará tucumã oil. However, in terms of added value both oils have potential applications in various industrial segments.
Acesso aberto (Open Access)
Chemical composition of different muscle zones in pirarucu (Arapaima gigas)
(Universidade Federal do Pará, 2017-04) MARTINS, Mayara Galvão; MARTINS, Déborah Elena Galvão; PENA, Rosinelson da Silva
Identifying potential patterns in pirarucu (Arapaima gigas) composition, as a function of the different fish muscle zones (dorse, venter, ventrecha and tail), was the main objective of this research. For such, the different pirarucu muscle zones were evaluated, in order to obtain proximate composition and minerals content. It was also determined amino acids and fatty acids contents in fish muscle. The dorsal, ventral and tail muscle zones presented similar moisture (76.5-78.2%), protein (17.8-18.9%), total lipids (1.0-1.5%) and ash (0.9-1.2%) contents. On the other hand, the ventrecha zone presented 25.8% of protein and the major total lipids content (17.1%). The main minerals found in fish muscle were K (183.5-288.6 mg/100 g muscle) and Na (65.1-175.5 mg/100 g). Glutamic acid (3027.6 mg/100 g muscle) was the main amino acid found in fish muscle, which presented 48% of essential amino acids in the protein fraction. Lipids content showed 57.3% of unsaturated fatty acids and 42.7% of saturated fatty acids.