Dissertações em Ciência e Tecnologia de Alimentos (Mestrado) - PPGCTA/ITEC
URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/8949
O Mestrado Acadêmico em Ciência e Tecnologia de Alimentos teve início em 2004 e funciona no Programa de Pós-Graduação em Ciência e Tecnologia de Alimentos (PPGCTA) do Instituto de Tecnologia (ITEC) da Universidade Federal do Pará (UFPA).
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Dissertação Acesso aberto (Open Access) Adsorção de cobre (II) presente em cachaça utilizando quitosana obtida por radiação micro-ondas: caracterização e estudo cinético(Universidade Federal do Pará, 2020-02-27) SANTOS, Lucely Nogueira dos; FERREIRA, Nelson Rosa; http://lattes.cnpq.br/3482762086356570; https://orcid.org/0000-0001-6821-6199Cachaça is a typical drink in Brazil and has been reaching more and more the national and international market. The cachaças produced in copper stills present unique characteristics, however they may be more susceptible to suffer contamination by copper (II). Adsorption by biopolymers has shown to be a very promising technique for the removal of metal ions. Chitosan is a biopolymer derived from the deacetylation of chitin and has free amino groups in its structure, which are strongly reactive to metal ions. Considering the aforementioned aspects, this work aimed to perform the deacetylation of chitosan using microwave irradiation technology and to evaluate the capacity of the chitosan obtained in adsorbing copper (II) from cachaça. Chitin was extracted from shrimp exoskeleton, chitosan was deacetylated and its adsorption capacity was evaluated through kinetic study using mathematical models. The copper (II) concentration remaining in the cachaça, in all kinetic experiments was estimated by the spectrophotometry technique in the visible region and confirmed by microwave-induced plasma optical emission spectrometry (MIP OES). Chitosan was characterized by infrared spectroscopy with attenuated reflectance (FTIR-ATR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and molecular mass The results of the characterization showed that the microwave deacetylation process it occurred efficiently, since the chitosan obtained had satisfactory properties in terms of its main characteristics observed, degree of deacetylation (above 85%), molecular weight, morphology and crystallinity. Regarding the adsorption kinetics, the best condition for copper adsorption was 6 mg of chitosan per mL of cachaça, in an equilibrium time of 60 min which resulted in a reduction rate of 84.09% of copper in the drink, according to results obtained by MIP OES. The kinetic analysis indicated the best fit of the data by the Elovich equation, suggesting that the chemisorption mechanism controls the kinetic process. Therefore, chitosan proved to be a good adsorbent for the removal of copper in cachaça and in this respect, a promising target for future technological investments.Dissertação Acesso aberto (Open Access) Aproveitamento de resíduos da indústria de óleos vegetais produzidos na Amazônia(Universidade Federal do Pará, 2014-12-17) SANTOS, Marcio José Teixeira dos; CARVALHO JUNIOR, Raul Nunes de; http://lattes.cnpq.br/5544305606838748; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170The objective of this study was the use of açaí waste, cupuassu and Brazil nut resulting from mechanical pressing of oil. In this context, the physico-chemical analysis of pies were made, and were subsequently applied oil extraction methods. Extraction methods were used: bligh dyer, sohxlet and supercritical fluid. We evaluated the efficiency of the extraction, the fatty acid profile, physico-chemical properties and the oxidative stability of oils obtained. Evaluating the results obtained, it could be said that the pies are an important source of nutrients, especially lipids, protein and fiber. The profile of fatty acids obtained Brazil nut pie, cupuassu pie and blend Brazil nut - cupuassu had higher unsaturated fatty acids, however, these tests showed the lowest time of oxidative stability. The extraction of oil from cupuaçu pie, applying supercritical fluid extraction and bligh dyer, obtained a ratio (ω-3 / ω-6) more significant when compared to the other raw materials and for the three extraction methods. Oil samples showed elevated levels of acidity, up establishing the RDC n ° 270. Regarding the peroxide values, with the exception of oil açaí pie, cupuassu - açaí blend and blend Brazil nut - açaí, all other samples showed peroxide values below that establishes the resolution. The oils obtained from mixtures had higher oxidative stability than the pure oil extracted from the pie, as well as profiles of more balanced fatty acids. The oils obtained from mixtures had higher oxidative stability than the pure oil extracted from the pie, as well as profiles of more balanced fatty acids.Dissertação Acesso aberto (Open Access) Avaliação da composição química, atividade antioxidante e antimicrobiana do óleo de cipó-de-alho (Mansoa standleyi) (Steyerm.) A. H. Gentry (Bignoniaceae) obtido via extração supercítica(Universidade Federal do Pará, 2019-05-31) URBINA, Glides Rafael Olivo; CARVALHO JÚNIOR, Raul Nunes de; http://lattes.cnpq.br/5544305606838748; https://orcid.org/0000-0002-4433-6580Mansoa standleyi is popularly known as "cipó-de-alho" because of its characteristic garlic odor (Allium sativum). The plant has an inhibitory effect on bacteria and fungi growth. The objective of this work was to evaluate the chemical composition, antioxidant and antimicrobial activity of the oil obtained from M. standleyi leaves via supercritical fluid extraction (SFE) and conventional extraction (Hydrodistillation). The SFE tests were performed using supercritical CO2, static extraction time of 30 min and dynamic time of 180 min, CO2 flow of 2.5 L/min and raw material mass of 10 g. The temperature and pressure variables were selected in order to obtain a difference in the CO2 density (𝜌𝐶𝑂2) in the 35 and 45 ºC isotherms combined with the pressure values of 100, 200, 300, and 400 bar. The results obtained allow us to verify that the global yield values of SFE on dry basis show significant differences between them (p≤0.05), with values varying from 0.87 to 2.02%. The highest average found refers to 400 bar/35 ºC condition (𝜌𝐶𝑂2 = 972.26 kg/m3). However, in Hydrodistillation extraction the oil yield was 0.14%. The results of phytochemical screening by high performance thin layer chromatography (HPTLC) evidenced the presence of terpenes, fatty acids, phenolic compounds, and flavonoids. It was demonstrated the presence of substances with antioxidant activity for all oils obtained with SFE, being observed a better identification in the oils obtained at high pressures. In the quantitative analysis of chemical composition, it was observed that the values ranged from 31.87 to 72.06 mg EAG/g oil in the content of total phenolic compounds. In relation to the antioxidant activity, the values ranged from 457.64 to 2475.55 EC50 expressed in g of oil/g of DPPH, the best results being obtained in the condition of 400 bar/35 ºC. In the fatty acid profiles of M. standleyi oil obtained by SFE, the results indicated that there was a difference in the fatty acids qualitative composition detected, in function of the operational extraction condition, where the presence of linoleic (≅95%), palmitic (≅12%), and oleic (≅5%) acid was observed. The chemical constituents identified in the obtained oil by Hydrodistillation were identified as sulfur compounds, phenols, and alcohols. The antimicrobial activity in vitro analysis showed that the oil obtained by SFE presents an antibacterial action against Stapphylococcus aureus and Escherichia coli. Finally, M. standleyi oil represents an alternative for future use in the treatment of diseases caused by microorganisms.Dissertação Acesso aberto (Open Access) Cinética de degradação térmica de folhas de mandioca (Manihot Esculeta Crantz) durante tratamentos de secagem em estufa e cocção(Universidade Federal do Pará, 2018-03-29) MODESTO JÚNIOR, Elivaldo Nunes; CHISTÉ, Renan Campos; http://lattes.cnpq.br/0583058299891937; https://orcid.org/0000-0002-4549-3297; PENA, Rosinelson da Silva; http://lattes.cnpq.br/3452623210043423Cassava leaves (Manihot esculenta Crantz), despite their use in animal feeding as silage, hay, or raw material, they are commonly used for human consumption in regional dishes in the North and Northeast of Brazil. Cassava presents cyanogenic glycosides in its composition linamarin and lotaustralin, which release hydrocyanic acid (HCN) after hydrolysis. The goal of this work was to study the effect of temperature and time of thermal processes application on the degradation of HCN from cassava leaves in order to establish processing conditions to obtain a safe product for human consumption. The cassava leaves were collected after six months of cultivation in a cassava farm from Salvaterra (Marajó-PA). Nine varieties of cassava leaves were characterized regarding their moisture, pH, total acidity, ashes, total lipids, crude protein, water activity, carbohydrates, total energetic value and HCN contents. Among the nine varieties, three of them were submitted to drying process at different temperatures and the thermal degradation of HCN was studied under drying and boiling conditions. The physicochemical characteristics of all studied cassava leaves were similar and total HCN content varied from 90.64- 560.88 mg HCN/kg leaves (total HCN, wet basis) and free HCN 16.65-59.24 mg HCN/kg leaves (free HCN, wet basis). Concerning the drying process, the increase in the temperature increased the effective diffusivity (Deff) of cassava leaves, which facilitates water loss; and temperatures above 50 °C are more effective. Thermal degradation studies of HCN showed that the drying and boiling processes were effective on total HCN removal after 180 minutes. Furthermore, a remarkable decrease in HCN contents was observed after 20 minutes of boiling, since the water facilitates HCN volatilization during the cooking process. Regarding free HCN, the drying method was more effective than cooking, showing high degradation percentages 74.07%- 92.19%).Dissertação Acesso aberto (Open Access) Desenvolvimento e aplicação de solventes eutéticos naturais profundos (NADES) para a extração de compostos bioativos da pitaya (Hyloreceus costaricensis)(Universidade Federal do Pará, 2020-08-12) PIRES, Ianê Valente; RODRIGUES, Antonio Manoel da Cruz; http://lattes.cnpq.br/7524720020580309; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170NADES (Natural Deep Eutectic Solvents) have been highlighted as an alternative to traditional solvents in the fields of green chemistry. They consist of a mixture of two or more components with specific properties that form a liquid at room temperature, and their main advantages are high biodegradability, low cost and non-toxic factors. In this research, lactic acid, glycine, ammonium acetate, sodium acetate, and choline chloride were studied to obtain NADES, which were prepared with and without the addition of water. The NADES synthetized in aqueous médium, showed lower viscosities and densities, but there was no difference in the vibrating modes in the FTIR and Raman spectra when compared to those prepared without water addition. NADES synthesis has been confirmed by two different techniques, FITIR and Raman spectra, by targeting hydrogen bonds formation. Because of its notoriety in the market and in the scientific field, the pitaya (Hyloreceus Costaricensis) was used for the extraction study with NADES. The best results for bioactive compounds extraction (193.18 and 186.08 mg 100g-1 b.s) were found, respectively, in NADES formed by lactic acid with glycine and lactic acid with ammonium acetate, both with water addition.Dissertação Acesso aberto (Open Access) Estudo dos riscos e benefícios associados ao consumo de três espécies de peixes da Amazônia(Universidade Federal do Pará, 2019-09-20) GOMES, Luciana Cristina Mancio; LOURENÇO, Lúcia de Fátima Henriques; http://lattes.cnpq.br/7365554949786769Fishing is one of the most explored activities in the amazon region, fish is an important protein source, however, it can represent one of the main vehicles of contamination due to its great capacity to bioaccumulate substances in tissues such as muscle and organs, being considered excellent bioindicators of the species. Its habitat. The aim of the present work was to study the amazonian species, curimatã (prochilodus nigricans), goby hake (macrodn ancylodon), and pyramutaba (brachyplatystoma vaillantii) by investigating the risks or benefits associated with consumption. In the muscle tissue and liver of the fish in different seasonal periods (rainy and dry season) amino acid and fatty acid profile analyzes were performed by liquid and gas chromatography. The determination of essential elements (cu, fe, mg, na and zn) was quantified by flame atomic emission spectrometry and the contaminants, lead (Pb) and mercury (Hg) by graphite furnace atomic absorption spectrometry. The validation of the methodology was performed through the addition and recovery method. The results obtained in the muscle and liver were correlated with biometric data, species feeding habits and the limits established by the national health surveillance agency for human consumption. The calculation of the tolerable weekly intake index (PTWI) was applied for the toxic elements pb and hg in different seasonal periods. According to the results, the species presented oleic (n-9), linoleic (omega-6) and arachidonic (omega-6) polyunsaturated fatty acids in the muscle, whereas in the liver the three species were c18:0, c18:1ω9, c18:2ω6, c20:4ω6, c22:6ω3. The total saturated fatty acid contents identified were higher in piramutaba, polyunsaturated in hake and monounsaturated in curimatã. Regarding the amino acid profile of the fillets, the highest predominance was histidine, alanine and serine. The species studied presented high levels of monounsaturated and polyunsaturated fatty acids. The monounsaturated ones presented higher contents in the curimatã species and the polyunsaturated ones were higher in the hake, both in the muscle and liver. Regarding minerals, calcium levels were quite significant between species in different seasonal periods, being predominant in the dry season, while Fe, Cu, Na and Zn presented higher levels in the rainy season. In the liver, during the rainy season, Mg, Zn and Cu values had average concentrations in curimatã specimens. While in the dry season the ca, mg, na and zn contents had higher predominance among the species. Regarding contaminants, pb levels were higher than the limit allowed by the legislation, showing significant behavior in relation to seasonality. The hg content in the three species was higher in the rainy season, the curimatã species reached higher levels in the muscle. In the liver, the levels of Hg in the rainy season were above the limit recommended by the legislation. In the dry season, the curimatã species contributed the most with 131.79%, exceeding the tolerable weekly limit of hg consumption, being considered inappropriate. According to the estimated weekly intake of toxic elements (PTWI) during the rainy season, acceptable limits were found among the contaminants. However, in the dry season, curimatã contributed the most with 131.79%, exceeding the tolerable weekly consumption limit. From Hg. It is concluded that the constant biomonitoring of the species commercialized in Belém-PA and surroundings that may present some contamination by toxic elements is necessary, thus avoiding possible reflexes and the compromise of human health and fish reproductive process.Dissertação Acesso aberto (Open Access) Folhas de mandioca cozidas: avaliação do processamento e estudo de uma etapa de detoxificação(Universidade Federal do Pará, 2019-08-21) LEHALLE, Ananda Leão de Carvalho; ABREU, Laura Figueiredo; http://lattes.cnpq.br/9379947446021216; https://orcid.org/0000-0001-7286-4789; LIMA, Consuelo Lúcia Sousa de; http://lattes.cnpq.br/2971385954203459This study evaluated the technological processes used to produce cooked cassava leaves (cooked manioc) considering the insertion of a detoxification process (rest test), aiming at reducing the total cyanide content. Ten samples of cooked cassava leaves commercialized in the city of Belém-PA were collected, five from fairs and five from supermarkets, where analyzes of cyanogenic (total cyanide, non-glycosidic cyanide and free cyanide), microbiological and physical contents were performed. -chemistry. The processes for producing cassava leaves cooked at fairs and agro-industries were verified. Good Manufacturing Practices (GMP) were verified by applying a checklist to two agro-industries. To study the detoxification process (rest test) the leaves were ground and remained at rest without and with added water at the times: 1.5; 3; 4.5; 6 and 24h, being performed analysis of cyanogenic compounds in all tests and pH only in fresh leaves and homes of 24h. Four processes of production of cooked cassava leaves were reproduced on a laboratory scale: two used in fairs and agroindustries (1 and 2) and two considering the rest tests that showed greater elimination of cyanogenic compounds (3 and 4). In the product of each assay, pH, cyanogenic and microbiological compounds analyzes were performed. Cyanogenic compound contents were determined by spectrophotometric reading at 605 nm. Microbiological analyzes were performed of: Salmonella spp, Bacillus cereus counts, coagulase positive staphylococci, coliforms at 45 ° C, mesophilic aerobes and mold and yeast. The physicochemical analyzes of moisture, ashes, proteins, lipids, carbohydrates, fibers, pH determination by direct reading in potentiometer and Total Titratable Acidity (TTA) were performed. The results of the cyanogenic compounds will vary from 1.25 to 8.22 mg HCN / kg, being 100% above the free cyanide legislation. All samples complied with legislation for Salmonella spp, coagulase positive staphylococci and Bacillus cereus. For coliforms at 45 ° C, 60% of the fair samples and 20% of the supermarket were in compliance with the legislation. The results of mesophilic and mold aerobic and yeast ranged from <2.40 to 5.38 and <2.88 to 7.30 log CFU / g, respectively. The fair samples were below the minimum recommended for humidity, lipids and pH and the supermarket samples, below the established for ashes, lipids and pH. Agroindustries were considered to be at high risk compared to GMP. The results of the detoxification study show significant difference between the pH of fresh leaves and the resting time of 24 h. The 6h rest tests with and without water showed greater elimination of cyanogenic compounds, so they were used in laboratory scale processing. Regarding the results of the processes on laboratory scale, There was no significant difference in the pH of fresh leaves compared to the products of the processes nor between the products 1, 3 and 4, in relation to the cyanogenic compounds and microbiological parameters. Changes in processing influence the contents of cyanogenic compounds, as well as the scarcity of GMP preceded by contamination. Resting tests contributed to the elimination of part of the cyanogenic compounds, however much of the conversion and elimination of HCN occurred in the leaf milling process, being this primordial step for detoxification and the previous grinding cooking proved unsatisfactory in relation to the parameters. cyanogenic and microbiological.Dissertação Acesso aberto (Open Access) Influência do fungo cladosporium cladosporioides no índice de qualidade e perfil aromático de sementes de cacau (Theobroma cacao L.) fermentadas(Universidade Federal do Pará, 2020-11-17) KONAGANO, Evelyn Mayumi Hanawa; FERREIRA, Nelson Rosa; http://lattes.cnpq.br/3482762086356570; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191Cocoa is a fruit that has great scientific and economic importance. However, the existing microbial diversity between lots and locations, results in different products, in relation to physical, chemical and sensory attributes. Thus, Araujo et al. (2014) proposed variables that can be used in order to standardize the quality indices of this raw material, in addition to what is already governed by legislation. In addition, there are several studies that use starter cultures of bacteria and yeasts in the fermentation of cocoa seeds, in order to obtain beans with superior quality and desirable aromas, in addition to resulting in a more homogeneous fermented raw material between different batches and locations. However, there are still no reports of the use of filamentous fungi as a starter culture, despite having biotechnological potential, mainly due to the excretion of several enzymes. A species that has already been reported in the fermentation of cocoa seeds is Cladosporium cladosporioides, which produces antifungal metabolites aimed at plant pathogens, in addition to having pectinase, laccase, glucanase, amylase, cellulase and xylanase enzymatic activity, important for the improvement of the cocoa bean fermentation process. The objective of this study is, therefore, to evaluate the influence of this filamentous fungus during the fermentation process, in an unprecedented way, through physicochemical and microbiological analyses. For this, two fermentation experiments were carried out: without inoculum (control) and with starter culture. The use of filamentous fungus did not significantly impact the formation of aromatic compounds in the almonds, compared to the control experiment. However, the presence of C. cladosporioides had a significant influence on the percentage of well-fermented almonds (p ≤ 0.05), through the cutting test, as a probable consequence of the lower content of total phenolic compounds, and of catechin and epicatechin. In addition, there was a lower concentration of acetic acid and a higher content of bioactive amines (p ≤ 0.05), when compared to the control experiment. These observed aspects were confirmed through multivariate analysis. Based on these results, it can be said that the use of C. cladosporioides proved to be promising and could provide improvements in fermented and dried cocoa beans.Dissertação Acesso aberto (Open Access) Otimização da pasteurização da polpa de jambolão (Syzygium cumini lamarck)(Universidade Federal do Pará, 2014-11-21) AMÉRICO, Gilciane Vergolino; CARVALHO, Ana Vânia; http://lattes.cnpq.br/7856575452724939; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191The Syzygium cumini Lamarck fruits, popular known as jambolan, are a source of anthocyanin and antioxidant. This study aimed to optimize the thermic pasteurization of the jambolan pulp, with the purpose to inactivate the enzymes, the bioactive compounds and the antioxidant activity retention. Physical analyses: transverse length (2,49cm), longitudinal length (1,68cm) and percent yield (57,22%); and physicochemical: moisture (89.43%) ash (0.27%), lipid (0.23%), protein (0.72%), acidity (5.99% citric ac.), soluble solids (9,17 ° Brix), pH (3.34), total phenolic (182.01 mgGAE.100g-1), total anthocyanin (93.56 mg.100g-1) and antioxidant activity by DPPH method (EC50 = 4552.26 g / gDPPH) and ABTS (18,48 μMTrolox / g) were performed. Due to a resistance while trying to flow the jambolan pulp in the pasteurizer pipes, the pulp was diluted and complied with the national legislation (Brasil, 2003) for tropical juice. The methodology used was a central composite design (2²), using as independent variables: temperature (°C) and time (s), and as response variables: total phenolic compounds, total anthocyanin, antioxidant activity (DPPH and ABTS) and enzymatic activity (POD and PPO). The enzymes of the jambolan tropical juice were completely inactivated, except for POD in the test treated with 85ºC/39sec. The independent variables and the interaction of them didn’t influence significantly at 95% of confidence level in the results obtained to generate predictive models of the characteristics evaluated, except for the total phenolic content. The best condition to obtain a maximum retention of the compounds analyzed and the complete inactivation of the enzymes was the temperature 92ºC and time 70sec for tropical juice of jambolan which was pasteurized.
