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BDTD - Biblioteca Digital de Teses e Dissertações

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Biblioteca Digital de Teses e Dissertações da UFPA (BDTD). Sistema Eletrônico de Teses e Dissertações (TEDE). Projeto BDTD/UFPA e Instituto Brasileiro de Informação em Ciência e Tecnologia (IBICT).

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Acesso aberto (Open Access)
Avaliação dos efeitos da desodorização da gelatina de pele de pescada amarela (Cynoscion ocupa) por diferentes métodos
(Universidade Federal do Pará, 2023-04-14) RABELLO, Fernanda Sales; LOURENÇO, Lúcia de Fátima Henriques; http://lattes.cnpq.br/7365554949786769
Fish skins are considered good sources to extract high quality gelatine for applications in the food industry, however, this fish gelatine may have a characteristic odor and taste, causing limitations for its application, especially as a food ingredient and in supplements. Several methodologies have been studied in order to remove or reduce the odor in products made with fish. Among these techniques, we can find degreasing and adsorption. The objective of this research was to deodorize the gelatine from the skin of yellow hake (Cynoscion acoupa) using three different methodologies: activated charcoal, ethanolic delipidation and their combination. Gelatin was obtained from the immersion of the skins in acidic and alkaline solutions. The desorization by delipidification occurred with the use of an ethanol solution (1:2) and the adsorption made use of activated charcoal in powder (0.5%) and in grain (0.7%). Analyzes were carried out to evaluate the physical-chemical, technological and sensorial quality of the gelatins. The analysis results were submitted to ANOVA and Tukey Test (p <0.05). All physicochemical parameters analyzed in the present study showed a significant difference between the studied variables, except for proteins, lipids and moisture. The variables of emulsifying capacity, gel strength, melting point showed a significant difference between the deodorization methodologies in relation to the control treatment. The EGAC treatment influenced the higher luminosity of the samples, presenting negative values in the a* parameter. The treatment with powdered activated charcoal influenced the lower chromaticity and lower yellowish tone. According to the electropheretic profile, samples E, ACP and EGAC showed collagen α and γ bands. From the FTIR analysis, the presence of activated carbon in the desorizations (ACP, GAC and EGAC) resulted in lower interactions with the amine group. In the sensorial evaluation, the samples deodorized with activated charcoal behaved similarly in the sensorial evaluation, highlighting the behavior of the EGAC sample.
Acesso aberto (Open Access)
Caracterização da gordura da amêndoa da gordura de cupuaçu (Theobroma grandiflorum S.) obtida por extração aquosa enzimática
(Universidade Federal do Pará, 2022-09-02) SILVA, Danylla Cássia Sousa; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170; https://orcid.org/0000-0002-6002-9425
Aqueous enzymatic extraction is considered an emerging green technique that is being extensively investigated. In this work, cellulase, pectinase and protease enzymes are used in the aqueous extraction process of cupuassu fat, aiming to obtain a higher extraction yield. Different incubation systems were tested, at a temperature of 60 °C and following extraction kinetics (2 to 8 hours). The samples that obtained the highest fat extraction efficiencies were analyzed: aqueous phase, in terms of phenolic compounds and antioxidant activity, and oily phase (fats) characterized in terms of physicochemical properties, fatty acid profile, oxidative stability, thermal and bioactive compounds. The aqueous phase showed higher concentrations of phenolic compounds and antioxidant activity when compared to the oil phase. The fat samples showed approximate contents of monounsaturated and saturated fatty acids with higher concentrations of oleic and stearic, showed good oxidative stability (about 14 h) and thermal stability (close to 406 oC) and the best yield result (80.86 %) was achieved with the protease enzyme within 6 hours of incubation. The results indicated that cupuassu fats obtained by enzymatic aqueous extraction have potential for use in the food, pharmaceutical and cosmetics sectors.
Acesso aberto (Open Access)
Cinética de secagem do camarão-da-amazônia (macrobrachium amazonicum) por refractance window
(Universidade Federal do Pará, 2023-10-19) ROSA, Matheus Yury de Oliveira; RODRIGUES, Antonio Manoel da Cruz; http://lattes.cnpq.br/7524720020580309
In the Amazon region, freshwater prawns are distributed throughout the hydrographic subbasins. Macrobrachium amazonicum, popularly known as the Amazon Prawn, is the species with the highest production in the region and has the greatest potential for fishing and aquaculture. Its capture and commercialization are one of the main and sometimes the only source of income for several families, especially those living along the riversides, due to the final destination of this production, with distribution in ports in Pará and Amapá. Although prawns are known for their high nutritional value, this characteristic can be affected when this food does not undergo a suitable preservation method to extend its shelf life. Given the importance of this food, it is necessary to explore new technologies, such as the use of ethanol in food pretreatment - which has the ability to dissolve cell membranes, alter the sample structure to be dehydrated, improve moisture transfer, and reduce drying time when combined with Refractance Window (RW) drying, a method that is known in literature as a technological innovation, in view of its advantages, which are: it retains bioactive compounds; it preserves quality and increases the product's shelf life; it has energy efficiency; it involves lower operating costs; and it is environmentally viable. The objective of this dissertation was to evaluate the performance of the RW drying method associated with ethanol pretreatment assisted by mechanical agitation and ultrasound in the dehydration process of an animal-based matrix (Amazon Prawn – Macrobrachium amazonicum). Simultaneously, mass transfer parameters and thermodynamic properties controlling the drying process were determined. The samples (peeled abdomen) were pretreated with 100% ethanol (1:18) under mechanical agitation (PTAG) and ultrasound (PTUS) for 10 minutes, in addition to the sample without pre-treatment (SPT). Then, the samples subjected to the drying process in RW at temperatures of 50, 70, and 90ºC. The parameters of the mathematical models by Dincer & Dost, Crank, and Motta Lima and Massarani were estimated using Origin Software 2023. The analyses were done in duplicate using analysis of variance (ANOVA) and the Tukey test at 5% probability. Additionally, the quality of fit for the experimental drying kinetics (CS) data was estimated by the coefficient of variation (R²) and the chi-squared (X²). After obtaining the data, the moisture determination indicated that at a temperature of 90ºC, the PTAG (12.93 ± 0.16%) and PTUS (11.86 ± 1.59%) samples had the lowest final moisture content. Through ANOVA, the results show that the ASPT and PTUS samples presented a significant difference, while the PTAG sample did not present a significant difference (p<0.05) between the temperatures. Regarding the mathematical modeling of CS, the Motta Lima and Massarani model showed the best fit to the experimental data, with R² ≥ 0.98 and reduced X² values for all temperatures. Thermodynamic properties were calculated based on data obtained by the Dincer & Dost model, such as activation energy (Ea) with a range between 42.97 - 30.37 kJ/mol; positive enthalpy (ΔH) values, indicating the need for heat energy for the drying process to occur; and negative entropy (ΔS) values, indicating that the process occurred without a significant increase in disorder in the system. Based on the results, it was evident that the combination of pretreatment with ethanol assisted by AG and US, coupled with RW drying, significantly reduced the time required for drying the Amazon Prawn.
Acesso aberto (Open Access)
Definição de condições ótimas para o processo de secagem em spray dryer da polpa de buriti (Mauritia flexuosa L.)
(Universidade Federal do Pará, 2022-02-09) CRUZ, Tatyane Myllena Souza da; MEDEIROS, Heloisa Helena Berredo Reis de; http://lattes.cnpq.br/9067574515452039; https://orcid.org/0000-0002-5234-840X; PENA, Rosinelson da Silva; http://lattes.cnpq.br/3452623210043423
Buriti (Mauritia flexuosa) is a native fruit of the Amazon, known for its functional potential, attributed to a high concentration of carotenoids. The spray drying process, in turn, can transform solution, suspensions or pastes into small droplets, which in contact with hot air produce powders with characteristics that favor the preservation of the product, in addition to facilitating storage and the transport. Thus, the objective of this work was to optimize the drying process of buriti pulp, in spray dryer, aiming to obtain a powdered product with desirable characteristics. For this, a central composite rotatable design (CCRD) was used to determine the influence of the variables: drying air temperature (130 – 190 °C), feed flow (7 – 17 mL/min) and carrier agent concentration (20 – 60%), on the product properties: moisture, water activity (aw), hygroscopicity, total carotenoid content, water solubility index (WSI) and the instrumental color parameter b* (fruit characteristic color parameter). To ensure the stability of the emulsion in the suspension, soy lecithin was added to all formulations, in the amount of 5% in relation to the dry matter of the sample. The response surface methodology (RSM) and the desirability function defined as optimal conditions for the drying process of buriti pulp: a gum arabic concentration of 60%, feed flow rate of 17 mL/min and drying air temperature of 190 °C; in the experimental domain. Under these conditions, the powder obtained had the following characteristics: 0.62 g/100 g moisture, aw of 0.16, hygroscopicity of 18.79 g/100 g, carotenoid content of 60.92 µg/g, ISA of 80.26% and a value of 31.32 for the chromaticity parameter b*.
Acesso aberto (Open Access)
Determinação de parâmetros de transferência de massa e de propriedades termodinâmicas na secagem curcuma longa L. usando a técnica de refractance window
(Universidade Federal do Pará, 2020-12-01) CUNHA, Natasha; RODRIGUES, Antonio Manoel da Cruz; http://lattes.cnpq.br/7524720020580309
The Curcuma Longa L. rhizomes (CL) presents a significant amount of starchy, lipids, vitamins, minerals and important bioactive compounds. The CL is an aromatic spice with natural dye action. However, these rhizomes are perishable, requiring dehydration treatment. The drying by Refractance Window (RW) is a very effective technique in the dehydration process. As far as we know, no information about dehydration or parameters prediction of mass transfer and thermodynamics of CL using this technique is available in literature. Thus, this study had as objective to determinate mass transfer parameters and thermodynamics properties that control the dehydration process of the Curcuma Longa L. by Refractance Window in different temperatures. (70, 80, 90° C), through applicability of the analytical model developed by Dincer e Dost (1995). It was observed that the dehydration process of the samples occurred in a small period. The unity content in natura was 80.71±1.12% (b.u) and of the dry product varied from 20.81 to 17.34% (b.u). The CL samples submitted to drying with exhaustion obtained a small influence on the drying fees when compared to the samples with no exhaustion. According to the model of Dincer & Dost, diffusivity of moisture varied from 5.21 × 107 m².s-1 to 12.89 × 107m².s-1 without exhaustion and 7.89 × 107 m².s-1 a 19.67 × 107m².s-1 with exhaustion and the mass transfer coefficient varied in the range of 9.79 × 105 to 6.73 × 105 m.s-1 without the exhaustion and 8.86 × 105 a 0.51 × 105 m.s-1 with exhaustion. All the entropy values (ΔS) obtained related to the drying of the CL by RW were negative (ΔS < 0). The study showed that the exhaustion system had a small influence on the mass transfer flee during the drying of the CL sample. The thermodynamics properties pointed to a nom spontaneous process with positive values of enthalpy and free energy of Gibbs, and negative values of entropy.
Acesso aberto (Open Access)
Discriminação da origem geográfica e quantificação de parâmetros de qualidade em sementes sementes de cacau (Theobroma cacao) cultivadas na amazônia utilizando espectroscopia no infravermelho próximo e ferramentas quimiométricas
(Universidade Federal do Pará, 2022-06-03) FERREIRA, Fabielle Negrão; OLIVEIRA, Marcos Enê Chaves; http://lattes.cnpq.br/9052059910078575; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191; https://orcid.org/0000-0002-8584-5859
This work discusses the application of the Near Infrared Vibrational Spectroscopy (NIR) technique in cocoa samples from different regions of the state of Pará (Medicilandia, Tucumă and Tomé-açu) with the aim of predicting major components and discriminating these different geographic regions. The NIR technique was associated with exploratory analysis of spectral data, testing different regression and discrimination models. This research is divided into three chapters. The first chapter reviews the concepts related to the NIR technique, and explores the most diverse articles on the application of the NIR technique in cocoa for different evaluations, such as, for analysis of major components, identification of fraud and discrimination of cocoa in different regions, from the planet. In the second chapter, prediction models were developed for nitrogen, moisture and total lipids in non-fermented samples, since certain cocoa components are not altered during fermentation, so these major components of the seeds could be quickly predicted by FT spectroscopy-NIR using PLS regression. The third article presents the application of NIR associated with exploratory analysis of spectral data by principal components, for discrimination of cocoa beans under five different treatment conditions (raw, dry fermented, dry unfermented and fermented defatted), from the three different regions mentioned geographic areas, and the best results were obtained when evaluating the fermented cocoa samples from the three regions.
Acesso aberto (Open Access)
Elaboração e caracterização de filmes a partir de farinha de pupunha (Bactris gasipaes), quitosana e glicerol pelo método de casting
(Universidade Federal do Pará, 2019-06-26) COSTA, Rebeca Desireé Sousa da; RODRIGUES, Antonio Manoel da Cruz; http://lattes.cnpq.br/7524720020580309; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170
Environmental problems caused by packaging manufactured from non-biodegradable and renewable sources have led to increased interest and attention from industry and researchers in terms of films and edible toppings development. Films are usually obtained from polymers such as polysaccharides, proteins and lipids, used to help maintain the quality and food shelf life. Thus, the aim of this study was to develop films using the casting technique from biodegradable sources with antimicrobial activity, in addition to evaluate the mechanical, barrier, optical, structural and thermal properties as well as to analyze the rheological behavior of the different filmogenic suspensions. The films were prepared with different ratios of peach palm flour, chitosan and glycerol. The presence of chitosan led to an improvement in the mechanical, optical and morphological properties of the films; however, they did not show antimicrobial activity against foodborne pathogens as E. coli and S. aureus. The rheological study showed that all the filmogenic suspensions presented non-Newtonian fluid behavior, with dilating characteristics. The Herschel-Bulkley and Bingham models were tested, and both fit satisfactorily to the rheological data, presenting high values for the R2 factor and low values for the χ2 factor. The results obtained for the fluid behavior index (n) presented values of n> 1 for all the samples, proving the dilator behavior of the suspensions. The films obtained presented a smooth and homogeneous surface, slightly soluble, permeable to water vapor, yellow coloration due to the high content of carotenoids present in the peach palm. FTIR spectra revealed the presence of the group amide I and the films exhibited the type C X-ray pattern. After 15 days in soil, the films lost 30% of its initial weight. Therefore, films obtained exhibit properties / properties similar to conventional films, with the advantage of being biodegradable from renewable sources and can replace the current packaging.
Acesso aberto (Open Access)
Estudo da influência do extrato purificado do açaí (euterpe oleracea) em filmes de gelatina e seu comportamento como indicador de pH
(Universidade Federal do Pará, 2019-05-14) BRITO, Raíra Sá de; LOURENÇO, Lúcia de Fátima Henriques; http://lattes.cnpq.br/7365554949786769; https://orcid.org/0000-0001-5009-8235
Acesso aberto (Open Access)
Estudo das etapas de obtenção e de armazenamento do pirarucu salgado-seco
(Universidade Federal do Pará, 2020-06-29) MARTINS, Mayara Galvão; PENA, Rosinelson da Silva; http://lattes.cnpq.br/3452623210043423
Arapaima gigas (Schinz, 1822) has promoted interest for commercial exploitation, due to its nutritional quality and sensory characteristics, as well as having a high rate of growth in captivity and a high carcass yield. Salting and drying are the main processes used in the fish muscle conservation, which is traditionally sold in the form of dry-salted. On the other hand, the processing of pirarucu does not have standard technological conditions and the sale of products also occurs without effective control, which compromises the quality products. Thus, this study aimed to assess the quality of commercial dry-salted pirarucu, as well as to study the process of obtaining dry-salted pirarucu, with satisfactory stability and quality. In the first chapter, a review of the literature on the themes addressed in the study is presented and in the following four chapters the main research results are presented. In the second chapter, a manuscript is presented that deals with the evaluation of the composition and physical-chemical quality of the dorsal and ventral regions of salted-dried pirarucu sold in the Metropolitan Region of Belém (Pará, Brazil). The composition and quality parameters (water activity, pH, total titratable acidity, instrumental color, total volatile bases, substances reactive to thiobarbituric acid and amine profile) from six commercial samples of the product were analyzed, to identify possible quality markers to be used during the processing and marketing of the product. The third chapter presents a manuscript with the results of the research, in which the impact of using different proportions of refined and coarse salt in the dry salting process of the dorsal and ventral regions of the pirarucu was evaluated. Additionally, the complementary drying process of the salted product was studied, as well as the possible changes of the product, during the storage period, in a standard atmosphere. In the fourth chapter, a manuscript published in the Food Research International magazine is presented, with the results of the research that evaluated the influence of the application of vacuum pulse and periodic vacuum pulses, as well as temperature, in salting process of the pirarucu muscle, by impregnation with sodium chloride. The fifth chapter presents a manuscript with the results of the study that compared the drying processes with hot air circulation and cold air circulation, of the pirarucu muscle impregnated with sodium chloride, using a periodic vacuum pulse. In this study, the hygroscopic behavior and the nutritional and sensory characteristics of the products obtained by the two drying processes were also evaluated
Acesso aberto (Open Access)
Extração de compostos bioativos de folhas de croton matourensis Aubl. com CO2 Supercrítico: determinação da composição química, atividade antioxidante e atividade biológica
(Universidade Federal do Pará, 2022-05-06) BEZERRA, Fernanda Wariss Figueiredo Bezerra; CARVALHO JÚNIOR, Raul Nunes de; http://lattes.cnpq.br/5544305606838748; https://orcid.org/0000-0002-2324-6287
The Croton matourensis species has health benefits, due to its composition, which has a high concentration of bioactive compounds such as phenolic compounds, terpenes, phenolic acids and phenylpropanoids. The most used method to obtain its extracts is hydrodistillation, however the extraction with supercritical carbon dioxide (SC-CO2) is an environmentally friendly method, with high selectivity and capable of obtaining extracts with a high concentration of larixol, an oxygenated diterpene of high economic value and with several biological activities. In this context, the present thesis aimed to use supercritical technology to obtain extracts from leaves of C. matourensis with a high concentration of larixol and to evaluate its potential anti-inflammatory, neuroprotective and antiviral activity against the COVID-19 virus. For this, in the first stage of the thesis, the extraction of C. matourensis leaves with SC-CO2 was carried out under different conditions of temperature (40 and 50 °C) and pressure (100 to 400 bar), the supercritical extraction was compared with hydrodistillation (HD) and hexane extraction (HE) through the evaluation of the mass yield, chemical composition and antioxidant activity of the extracts, then the experimental model of focal ischemia in the motor cortex of rats was carried out using the extract obtained in the best operating condition with SC-CO2. The highest yields were obtained in HE (5.73 ± 0.26%) and in the condition at 50°C/400 bar (5.60 ± 0.06%), which were statistically equal (p > 0.05), the supercritical condition was more advantageous in obtaining larixol (48.49%) compared to HE (2.93%). The extracts obtained by the different methods showed a high value of total phenolic compounds (51.81 ± 2.03 to 79.53 ± 1.19 mgGAE/g of extract), total flavonoids (2.50 ± 0.20 - 6.89 ± 0.45 mgQE/g of extract) and antioxidant activity with maximum inhibition percentage equal to 83.26 ± 0.58% at a concentration of 14 mg/mL. The focal cerebral ischemia study revealed that the animals treated with the C. matourensis extract showed a greater reduction in the lesion area than those treated with the control solution (Tween 5%), suggesting its potential anti-inflammatory and neuroprotective effect. In the second stage of the thesis, an in silico study was carried out to evaluate the interactions between the larixol ligand and four SARS-CoV-2 receptors. The molecular docking results showed that the mode of interaction played a fundamental role in the interaction with larixol, mainly in the interaction with Spike- protease. The study showed through the affinity energy that the ligand had stable conformations, forming a stable complex with the receptors, conforming to the catalytic site of the receptors. Molecular docking, molecular dynamics and Gibbs free energy data showed that larixol can bind to the binding compartment of receptors, evidencing its potential role as an antiviral agent or agent used in conjunction with other therapies that provide a line of defense against diseases associated with the coronavirus. Thus, the thesis showed that the extract of C. matourensis leaves obtained with SC-CO2 showed a high concentration of larixol, with potential anti-inflammatory, neuroprotective and antiviral activities, presenting potential to be applied as an input in the food, cosmetic and pharmaceutical industries.
Acesso aberto (Open Access)
Extração do óleo de uxi (Endopleura uchi) com CO2 Supercrítico: parâmetros de processo e qualidade funcional
(Universidade Federal do Pará, 2022-09-30) PINTO, Rafael Henrique Holanda; CARVALHO JÚNIOR, Raul Nunes de; http://lattes.cnpq.br/5544305606838748; https://orcid.org/0000-0002-4433-6580
The uxi (Endopleura uchi) is a native species of the Brazilian Amazon, with fruits consumed by the local population in natura forms or as pulp. Another form of food consumption includes the use of the stem for the production of herbal tea. However, the interest in the wood of this species by civil and naval construction contributes to the felling of trees, which harms the ecosystem. In order to contribute to the appreciation and consequent awareness for the preservation of the species, as well as to promote the application of the vegetable raw material in the industrial scenario, this work aimed to extract the uxi oil (Endopleura uchi) with supercritical CO2 at in order to identify the best process parameters, in addition to characterizing the product obtained (uxi oil) and potentializing possible applications as a functional food from the chemical composition. The uxi oil extraction process with supercritical CO2 was carried out at temperatures of 40 and 60 °C and pressures of 200, 300 and 400 bar using lyophilized pulp. The best extraction condition was observed at 40°C and 300 bar, with high overall yield, lower energy consumption and less work done by the pump. The chemical composition of the oil showed a predominance of unsaturated fatty acids, especially oleic (n-9) and linoleic (n-6) acids. Carotenoids were also quantified in the obtained product. The indices of atherogenicity (AI), thrombogenicity (TI) and the ratio of hypocholesterolemic/ hypercholesterolemic (H/H) indicated that uxi oil has good functional quality.
Acesso aberto (Open Access)
Farinha de mandioca (Manihot esculenta) e tucupi: uma abordagem analítica utilizando espectroscopia no unfravermelho próximo (NIRS) e ferramentas quimiométricas
(Universidade Federal do Pará, 2022-04-25) POMPEU, Darly Rodrigues; SOUZA, Jesus Nazareno Silva de; http://lattes.cnpq.br/3640438725903079; PENA, Rosinelson da Silva; http://lattes.cnpq.br/3452623210043423
The near infrared spectroscopy (NIRS) coupled to chemometrics has been used as an alternative tool for quick and reliable solutions. Cassava flour (CF) can be classified as fermented and non-fermented types. Tucupi is a yellow broth, acidic, mostly aromatic and widely used in Regional dishes in Para state. This thesis proposed to apply for the first time the NIRS associated with chemometrics to predict quality parameters from CF and tucupi, as well as to discriminate fermented and non-fermented CF. One hundred six samples of CF was investigated and nine physicochemical parameters of CF were evaluated. Calibration equations with independent validation were developed to predict all parameters using the partial least square regression method. The performance of models was evaluated by the root mean standard error of calibration (RMSEC) and validation (RMSEV), and R2 values. The aW (RMSEC = RMSEV = 0.05), moisture content (RMSEC = 0.35%; RMSEV = 0.45%) and pH (RMSEC = 0.16; RMSEV = 0.18) could be predicted (R2 > 0.727) by NIRS coupled to multivariate analysis. NIRS coupled to Principal Component Analysis–Linear Discriminant Analysis (PCA-LDA) was also used to investigate the classification of fermented and unfermented CF. The use of NIRS spectra allows to obtain better performance parameters (training accuracy: 86.3–93.8%; validation accuracy: 84.6–96.2%) to discriminate fermented and unfermented CF than the use of the physicochemical properties (training accuracy: 80%; validation accuracy: 84.6%). NIRS was also used to predict nine quality physicochemical properties of tucupi Sixty-five samples of tucupi were used in this study. The performance of models was evaluated by the R2, RMSEC, root mean standard error of cross-validation (RMSECV) and RMSEV values. The total soluble solids contents could be predicted (R2 > 0.727; RMSEC = 0.184%; RMSECV = 0.411%; RMSEV = 0.338%) by NIRS coupled to multivariate analysis. NIRS and chemometrics proved to be a powerful tool to predict quality parameters in CF and tucupi as well as to discriminate fermented and non-fermented CF.
Acesso aberto (Open Access)
Hidrólise da quitosana: obtenção de um extrato enzimático e caracterização do produto hidrolisado
(Universidade Federal do Pará, 2022-08-09) GONÇALVES, Cleidiane Gonçalves e; FERREIRA, Nelson Rosa; http://lattes.cnpq.br/3482762086356570; https://orcid.org/0000-0001-6821-6199; LOURENÇO, Lúcia de Fátima Henriques; http://lattes.cnpq.br/7365554949786769; https://orcid.org/0000-0001-5009-8235
Chitin, extensively found in crustaceans exoskeletons, insects, and microorganisms, has limited usage due to its low solubility in aqueous solution, requiring its partial deacetylation to obtain chitosan. Chitosan's depolymerization has attracted considerable attention, as its oligomers have high water solubility, biocompatibility, and non-toxicity, as well as beneficial properties such as antimicrobial, antioxidant, and antitumor properties. For this reason, in this research, a review article was produced (Chapter I) based on the main methods of chitosan hydrolysis, besides analyzing the parameters that influence the acquisition, and characteristics of hydrolysis results, effectively and at a lower cost. Among the approaches studied, enzymatic hydrolysis excels due to its control ease and performance under milder conditions, making it possible to use low-cost enzymes belonging to the glycoside hydrolases group. Thus, enzymatic hydrolysis was defined as a technique for various sizes of chitosan acquisition (Chapter II) through the production of an enzymatic extract (integral enzymatic extract - IEE) from a filamentous fungus strain. The enzyme identification present in the IEE showed exo-chitinases, endo-chitinase, and cellobiohydrolase. Considering the same reaction conditions, the IEE showed greater efficiency than the commercial enzyme (Celluclast 1.5 L®), which was used as a parameter because it is an enzyme capable of cleaving the β-1,4-glycosidic bond of chitosan - similar to chitosanase, besides presenting a lower cost. The IEE reduced the molecular weight of chitosan by 47.80; 75.24 and 93.26% at 2.0; 5.0, and 24 h, respectively. Through the FTIR analysis, a lower absorbance of the spectral signals of chitosan oligomers was detected, and the crystallinity reduced after 3.0 h of hydrolysis. Based on this study, we can infer that enzymatic hydrolysis, under established conditions, is effective at obtaining lower molecular weight chitosan using unpurified crude extract.
Acesso aberto (Open Access)
Interesterificação enzimática de óleo de pracaxi, gordura de cupuaçu e estearina de palma: obtenção de gorduras especiais para aplicação na indústria alimentícia
(Universidade Federal do Pará, 2018-02-28) SILVA, Dayala Albuquerque da; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170
The methods of modification of oils and fats are widely applied in the food industry to obtain products with specific characteristics. Among these, the blending and interesterification stand out, through which the structured lipids are obtained. From the enzymatic interesterification, lipids can be obtained with greater control of the distribution of fatty acids than those obtained chemically. And its employs softer reaction conditions that interfere positively with the quality of the lipids obtained. However, although there are already several studies on obtaining lipid bases for application in the food industry through enzymatic interesterification, there are few studies applying as oilseeds of the amazon region. Thus, this study aimed to obtain special fats for application in the food industry through the blending and enzymatic interesterification of fats of amazon region (pracaxi oil, cupuassu fat and palm stearin). The binary blends between the oil and the fats were developed in ratios (w/w) 40:60, 50:50, 60:40 and 70:30. The Lipozyme TL IM (Thermomyces lanuginosus) was used. The reactions were carried out under the following conditions: at 60 ºC, 5% (w/w) of enzyme, agitation of 150 rpm and reaction time of 5 h. The pure samples and the blends were evaluated regarding of acidity, peroxide, melting point, iodine value, saponification value, fatty acid composition, triacylglycerol composition, oxidative stability, olid fat content and consistency. The samples’ nutritional quality was determined using the nutritional quality indexes (AI, TI and HH). Blends with more than 50 % of unsaturated fatty acids were obtained. The addition of pracaxi oil in the blends improved the nutritional quality indexes. The enzymatic interesterification caused the increase of the melting point for PC blends and the reduction for the PE blends. The same behavior was observed for the solid fat content. The blends obtained were suitable for use in fatty products, in special in the margarines, shortenings, bakery/confectionery fats and fat for frying.
Acesso aberto (Open Access)
Leveduras da fermentação do cacau amazônico: caracterização molecular e perfil de enzimas extracelulares
(Universidade Federal do Pará, 2018-08-29) ALMEIDA, Silvana de Fátima Oiveira de; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191
Scientific literature the most important step to obtain quality chocolate. The fermentation process is carried out by microorganisms naturally present in the utensils used to open the fruits, in the fermentation box and in the environment. The main microorganisms that carry out the fermentation of cacao are: yeasts, lactic and acetic bacteria. In order to obtain quality fermented almonds, it is essential to understand the role of yeasts, since these microorganisms initiate fermentation and remain throughout the process. The objective of this study was to isolate and identify the yeasts present during the cocoa fermentation and to investigate the ability of the isolated species to produce hydrolytic enzymes. The fermentations were carried out in farms, in the same way that the owners performed, both with duration of seven days and sample collection every 24 hours, for the identification of the yeasts the sequencing of the D1 / D2 region fragment of the 26S rRNA gene was carried out and amplified with universal primers for NL1GC and LS2 eukaryotes, at all fermentation times the temperature and pH of the samples were measured. A total of 44 yeast isolates were obtained from Medicilândia and 29 from Tucumã. In Medicilândia, the species Pichia manshurica and Saccharomyces cerevisiae were identified. In Tucumã five species Pichia fermentans, P. kudriavzevii, P. manshurica, S. cerevisiae and Zygosaccharomyces bailii. For the potency test in Medicilândia, 3 yeasts showed potential for the production of amylase, 10 for cellulase, 1 for lipase and 2 for proteinase, the yeasts that produced the enzymes were S. cerevisiae. In Tucumã S. cerevisiae did not produce any enzyme, the Pichia species obtained a positive result for the enzymes amylase, cellulase and phospholipase. Thus, this study proposes the importance of yeasts during cocoa fermentation, since the dominance of the Pichia and Saccharomyces genera was observed in the two localities of this research, and the production of hydrolytic enzymes from these species, which suggests that these yeasts can be used in biotechnological processes in the food industry.
Acesso aberto (Open Access)
Obtenção de Extratos Polissacarídicos do Cogumelo Comestível Pleurotus Ostreatus com tecnologia de fluido supercrítico
(Universidade Federal do Pará, 2020-03-13) BARBOSA, Jhonatas Rodrigues; BARBOSA, Jhonatas Rodrigues; http://lattes.cnpq.br/2588425611542447
The present dissertation proposal sought to develop an efficient method for recovery of extracts rich in polysaccharides from the edible mushroom Pleurotus ostreatus using binary system with hot water and supercritical CO2. The dissertation was structured in two interconnected chapters. Chapter I is a published article of review bibliographic, in which the latest findings of the literature on the subject are addressed clearly and factually, emphasizing the development of new extraction techniques, biological potential, and new technologies. Chapter II is a research article, where the main findings about the extraction and characterization process of a fraction rich in polysaccharides are displayed. The results show that the technology and process developed were efficient for recovery with a high yield of extracts rich in polysaccharides. In addition, research has shown that the extracts are a mixture of heteropolysaccharides, β-glucans, α-glucans, and oligosaccharides. The extract with the best extraction condition has high antioxidant activity, does not have cytotoxic effects, and has cytoprotective activity against free radicals. Thus, the method developed to recover extracts rich in polysaccharides is efficient, environmentally friendly and has potential for industrial implementation.
Acesso aberto (Open Access)
Óleos e gorduras da Amazônia: produção de bases lipídicas especiais por interesterificação enzimática e predição das propriedades físicas
(Universidade Federal do Pará, 2023-08-30) SILVA, Dayala Albuquerque da; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170; https://orcid.org/0000-0002-6002-9425
The lipid modification methods can increase the potential application of the Amazonian oils and fats in the food industry. In addition, the determination of the physical properties, such as density and viscosity, are fundamental to promote the industrial application of blends of oils and fats. In this context, the first part of this study aimed to obtain blendsin different proportions of pracaxi oil/cupuaçu fat (PC) and pracaxi oil/palm stearin (PS) (% w/w) (40:60, 50 :50, 60:40 and 70:30) and use enzymatic interesterification to change their properties. Pure samples and blends, before (NIE) and after (IE) enzymatic interesterification, were characterized. Samples with the greatest potential for food applications (ratio of 70:30) were characterized by X-ray diffraction, optical microscopy and thermal analysis. The second part of this study aimed to measure the density and viscosity of passion fruit oil, pracaxi oil and palm stearin, as well as their respective binary blends(40:60, 50:50, 60:40 and 70:30), at different temperatures (303.15 to 363.15 K). And perform the fitting of experimental data to mathematical models available in the literature for the prediction of these properties. The results obtained in the first part of the study indicated that the blends with the highest proportion of pracaxi oil (70:30) had the lowest indices of atherogenicity (AI) (PC 0.21; PE 0.34) and thrombogenicity (IT) (PC 0.38; PE 0.55). The fats (cupuassu fat and palm stearin) showed good oxidative stability (> 3.0 h) and contributed to increase the stability and plasticity of the lipid bases obtained. Enzymatic interesterification increased the plastic range of PC blends and reduced the solid fat contente (SFC) of PS blends. Interesterification caused a reduction in the consistency of the blends, which shows the improvement in textural properties. The β crystalline form was reduced in the interesterified blends. The crystals found in the blends showed more stable polymorphic forms, while the interesterified blends showed a reduction in the β crystalline form and the presence of crystals in the α form, which is less stable. In relation to the experimental determination and data modeling of density and viscosity of blends of passion fruit oil, pracaxi oil and palm stearin, it was verified that the linear model used for the prediction of the density behavior presented excellent adjustment parameters, with R 2 values greater than 0.99 (0.9927 – 1.0) and low RMSE values (3.14x10-5 – 1.19x10-3) and χ 2 (1.77x10-9 – 2.56x10-6). For viscosity, the Andrade, modified Andrade and Arrhenius models were the ones that presented the best fits, with coefficients of determination (R2) greater than 0.99 (0.9939 – 0.9993), and low RMSE values (5.72x10-3 – 4.78x10- 2) and χ 2 (0.0001 – 0.0032). Based on the Arrhenius model, it was found that pracaxi oil had the highest activation energy (28.21 kJ/mol), contributing to the greater sensitivity to temperature variation of PS blends. The models that presented the best fit parameters can be reliably used to predict the behavior of the pure samples and blends studied, and thus can be used to model the operations involved in the processing of these vegetable oils and fats.
Acesso aberto (Open Access)
Potencial de aplicação industrial de frutos de pupunha (Bactris gasipaes KUNT)
(Universidade Federal do Pará, 2018-06-25) PIRES, Márlia Barbosa; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170; RODRIGUES, Antonio Manoel da Cruz
The objective of this work was to evaluate the potential of industrial application of peach palm (Bactris gasipaes Kunt) fruits typical of the Amazonian region, which besides being a food source, presents great potential for industrial applications. The fruits are classified into three races according to their size: microcarpa (fruit <20 g); mesocarpa (fruit between 21 and 70 g) and macrocarpa (fruit> 70 g). For this study, three peach palm flour, one of each race microcarpa (MIF), mesocarpa (MEF) and macrocarpa (MAF) were elaborated. Flours were characterized and presented high energy potential (≥ 300 kcal / 100g) and high dietary fiber and starch content, as well as adequate technological properties, Water absorption capacity (≥ 255%) and Absorption capacity of oil (≥ 65%). Starches, extracted from flours by two methods, were characterized as to lipid content, protein, viscosity, swelling power, solubilization and amylose content. The results showed that although the starch contains a low amylose content, its gel is resistant to heat, maintaining its viscous behavior for longer. The low amylose content, (≤ 2.92 g.100g-1), was confirmed regardless of race, indicating the classification of peach palm starch as waxy starch. Starches with these characteristics are of great importance for industrial application, mainly in the food industry, where they are used to change or control characteristics such as texture, appearance and shelf life stability.
Acesso aberto (Open Access)
Uso de processo enzimático usando a obtenção de carotenoides da torta residual de dendê
(Universidade Federal do Pará, 2017-02-22) MESQUITA, Eric César Mano; CORRÊA, Nádia Cristina Fernandes; http://lattes.cnpq.br/5763999772352165
The residual fibers from the production of palm oil are a potential source of carotenoids of great economic importance, particularly β-carotene, due to its biological characteristics in human health and its pro-vitamin A. The enzymes cellulite have been shown to be a strong alternative to increase the yield in the oil extraction process, used particularly for the pretreatment of the constituent material of the plants, as it favors the release of the oil inside the plant cell, contributing to the increase of the amount of oil to be extracted and still reducing the extraction time, thus providing the efficiency of the extraction processes of compounds of industrial interest. In the pressed mesocarp pie (TMD), a pre-treatment with the enzymes cellulase (CELLUCLAST) and pectinase (PECTINEX) at the times of 3.6, 12, 24, 48 and 60 h was carried out to evaluate the highest volume yield carotenoid degradation. Then, the effect of the addition of the lipase enzyme was evaluated through a rotational central composite experimental design 2³, on the quality of the oil, in terms of β-carotenes (μg /gTMD48). The results for the pre-treated TMD indicate that 6 hours would be enough to reach this goal, obtaining 55% mass of carotenoids. For the results with addition of lipase, it was observed that in the highest concentration there was a decrease in acidity and an increase in the content of carotenoids. In the present study it was observed that hydrolysis did not occur as a function of the amount of water in the reaction medium favoring the opposite reaction, the esterification of the free fatty acids.