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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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Acesso aberto (Open Access)
Adição de ácido esteárico e surfactante em filmes elaborados com proteínas miofibrilares obtidas de corvina (micropogonias furnieri).
(Universidade Federal do Pará, 2017-03-03) VIEIRA, Lorena Limão; LOURENÇO, Lúcia de Fátima Henriques; http://lattes.cnpq.br/7365554949786769
The interest in biodegradable films as food packaging is a worldwide trend that has increased significantly in recent years. The myofibrillar proteins, particularly fish ones, have been gaining interest in film technology. The films made from polysaccharides or proteins have excellent mechanical and optical properties, but these films have a high water vapor permeability (WVP). The incorporation of hydrophobic substances, such as stearic acid, into the film-forming solution, is an alternative to increase the barrier properties of the film to water vapor. But to facilitate the incorporation of the lipid in the protein matrix, it is necessary to add surfactant, which are substances capable of interacting with the protein and the fatty acid. The objective of this work was to develop and characterize films of myofibrillar proteins obtained from corvina waste (Micropogonias furnieri) using glycerol as plasticizer, sodium dodecyl sulfate (SDS) as surfactant and stearic acid (SA) as lipid, to improve the technological properties of the film. The characterization of the waste and lyophilized myofibrillar proteins (MP) was performed, indicating that the raw material had a high protein content (96.03% b.s.), important for the formation of the biopolymer matrix. A complete factorial planning was done to define the region of better mechanical, physical and barrier properties of films. The optimized biofilm was prepared with 2.84% MP, 3.18% SA, and 78.41% SDS and 30% glycerol. Concentrations of SA and SDS significantly reduced the WVP, reaching 5.87E-11 g m m-² s-¹ Pa-¹, representing a reduction of 31% when compared to the control biofilm. The mechanical properties of the optimized biofilm were favored, presenting 235.60% of elongation and 6.35 MPa of tensile strength producing stronger and more flexible films. The values of transparency were high, indicating tendency to opaque and yellowish tone, however, with excellent UV barrier properties and it can be used in light sensitive foods. The optimized film also presented good thermal stability and the microstructure revealed a structural change in the filmogenic matrix, in relation to the control, with presence of grooves and protuberances on the surface, confirmed by X-ray diffraction, which indicated the influence of SDS and SA on crystallinity of the film. A 22% increase in solubility and a slight decrease in the swelling of the optimized film were observed.
Acesso aberto (Open Access)
Análise dos aspectos microbiológicos de peixes salgados comercializados no complexo do Ver-o-Peso e o impacto do processo de salga no crescimento de micro-organismos e na formação de aminas biogênicas
(Universidade Federal do Pará, 2017-08-01) BATTAGIN, Heloísa Valarine; RODRIGUES, Antonio Manoel da Cruz; http://lattes.cnpq.br/7524720020580309
Ver-o-Peso market is the main point of landing, processing and trading of salted fish in the metropolitan region of Belém and supplies several counties around. Thus, in order to provide better living circumstances for these communities, the present study aimed to analyze the hygienic/sanitary conditions of salted fish trading in the Ver-o-Peso market. Salting and manipulation processes of three fish species (king weakfish (Macrodon ancylon), thomas sea catfish (Notarius grandicassis) and laulao catfish (Branchyplastystoma vaillantii)) were evaluated. These species have huge commercial importance in the northern region of Brazil. The impact of salting processes on growth of microorganisms and biogenic amines accumulation was carried out in crevalle jack species (Caranx hippos). Although salting processes are simple to handle, when carried out by fishermen and fish handlers of Ver-o-Peso market the hygienic/sanitary conditions are not achieved, and management is inadequate, resulting in low-value products. The procedures mistakenly applied in fish salting and commercialization can afford the growth of microorganisms (such as staphylococci and thermotolerant coliforms) and the production of bioactive amines, which suggests the consumer may fall ill. Therefore, standardizing salting procedures and training fish handlers are necessary. The analysis of interactions among Gram-positive and Gram-negative bacteria in salted crevalle jacks (under controlled conditions) concluded these microorganisms behave in different manners under different concentrations of NaCl. The groups which presented more growth became involved in the production of higher concentrations of histamine, due to quorum sensing. In addition, drying process was positive in reducing the level of amines. Considering moisture, water activity and profile of amines, the association of salting and drying processes produced better quality products when applying 25% NaCl rather than 15% NaCl.
Acesso aberto (Open Access)
Aplicação da tecnologia supercrítica visando a valorização da casca do fruto do bacuri (Platonia insignis Mart.)
(Universidade Federal do Pará, 2021-08-17) FREITAS, Lucas Cantão; CARVALHO JÚNIOR, Raul Nunes de; http://lattes.cnpq.br/5544305606838748; https://orcid.org/0000-0002-4433-6580
The use of agro-industrial waste envisioning its valorization has generated interest from the scientific community and industries. Therefore, this work provides a comprehensive approach to the current state of the art in relation to the use of agro-industrial waste, emphasizing the obtainment of high value-added products through supercritical technology and other environmentally friendly technologies. In addition, the main products generated from the use of agro-industrial residues were reported and discussed in terms of process, feasibility and future perspectives. In this context, bringing to the Amazon scenario and putting into practice the current state of the art, it was decided to apply supercritical technology as a tool for valuing the agro-industrial residue of the bacuri fruit, more specifically its shell, as it is the largest fraction of this fruit, representing up to 70% in mass. Thus, the work aimed to develop a process for separating and/or minimizing the resin that exudes from the bacuri shell, since this is the main barrier to the technological use of this residue. For this, consecutive extraction with supercritical CO2 was applied, where the process parameters such as particle size, pressure and use of cosolvent were studied, in addition to the pre-processing steps. The extracts obtained were analyzed in terms of phenolic compounds and antioxidant activity (ABTS) by spectrophotometric methods. The results showed that the process was able to separate the resin from the bacuri shell, which is the first report described in the literature. Furthermore, the smaller particle size (0.25 mm) exhibited the most prominent impact on extraction rate, providing good yields of lipid extracts (up to 10.09 ± 0.02 %) and ethanoic extracts (up to 13.78 ± 0.41%). The obtained extracts presented good levels of phenolic compounds, which was associated with its high antioxidant activity. Thus, the application of supercritical technology added value to the bacuri shell, enabling new strands for industrial use of this residue with potential applications in the food, pharmaceutical and cosmetic industries, encouraging the circular economy and the bioeconomy of the Amazon region.
Acesso aberto (Open Access)
Avaliação do potencial nutricional e tecnológico da pupunha albina (Bactris Gasipaes)
(Universidade Federal do Pará, 2022-04-01) SOARES, Stephanie Dias; SANTOS, Orquídea Vasconcelos dos; http://lattes.cnpq.br/9446483074995655; PENA, Rosinelson da Silva; http://lattes.cnpq.br/3452623210043423
Among the species of fruit growing in the Amazon, the peach palm (Bactris gasipaes) is worth mentioning, with its different varieties in terms of pulp and peel characteristics, size, and shapes, and an important nutritional value. The natural hybridization promoted various plants and the origin of a palm tree with an albino fruit variety (white peel and pulp). Although there are fruits with yellow exocarp and white mesocarp, there is still no report in the scientific literature about albino peach palm. Thus, this research characterized pulp and pulp flour of raw and cooked albino peach palm. Macro and micronutrients, bioactive compounds, instrumental color, thermogravimetric and differential stability, spectral parameters, morphological structures, and functional and technological properties were evaluated. In the biometric evaluation, parthenocarpic fruits (without seeds) and fruits with seeds were observed; both constituted mostly by pulp (77%). The fruits of the albino peach palm were classified as a microcarp variety. The composition showed that carbohydrates and water were the main constituents of all samples. The cooking process increased the moisture content of the pulp but decreased its proteins, lipids, and carbohydrates contents. The colorimetric parameters indicated a significant browning and the intensification of the yellow color of the pulp after cooking. The content of bioactive compounds varied among the samples, been observed a reduction in the levels of total phenolic compounds and ascorbic acid in the pulp after cooking. The four samples presented a maximum loss of mass at 300ºC, with different thermogravimetric behaviors, according to the cooking and drying processes. The spectral patterns in the infrared region, for the pulps and flours, showed characteristic bands of organic compounds, especially hydroxyl OH, which are present in the structure of starches. Scanning electron microscopy showed amyloplast and fiber bundles with starches in the raw pulp and gelatinized starch granules in the cooked pulp and the flour from this pulp. The flour from raw pulp presented small and heterogeneous starch granules, with isolated amyloplast, attributed to drying and grinding operations. The two flours showed different granulometric distributions, but the highest proportion of both flours was retained in a 250 mesh sieve. Values of water solubility index were statistically different (p < 0.05) for both flours from raw and cooked pulp indicating that the cooking and drying processes increase the number of soluble constituents in the products. The water and oil absorption indices for both flour were significantly different (p ≤ 0.05). The results indicate that pulp and flour from the pulp of albino peach palm are raw materials important for consumption after cooking and to be exploited by the food, pharmaceutical, and biotechnological industries.
Acesso aberto (Open Access)
Caracterização de óleos e gorduras vegetais amazônicas: utilização de modelo para predizer viscosidade
(Universidade Federal do Pará, 2022-06-03) FREITAS, Joice Silva de; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170; https://orcid.org/0000-0002-6002-9425
The Amazon rainforest is rich in oilseed plant species, which have fruits that are attractive due to their economic potential and biological properties. Oils from oleaginous matrices have a unique composition with physicochemical and nutraceutical properties that attract attention as a source of fatty acids. The predictive model is based on the use of mathematical equations that are more comprehensive and less limited than simple linear or polynomial models, and are able to predict a certain property using one or more physicochemical parameters. Thus, this work aimed to use a predictive model to calculate the viscosity of Amazonian oils (açaí, bacaba, tucumã) and fats (cupuaçu, bacuri and tucumã). The samples were physicochemically characterized in terms of acidity index, density, oxidative stability, peroxide, melting point, iodine index, saponification index, fatty acid composition, triacylglycerol composition, solid fat content, atherogenicity index and heterogeneity. Two predictive models were used to obtain the viscosity values of oils and fats, the model using the profile of the mass fraction of polyunsaturated and monounsaturated fatty acids and the model using the iodine and saponification index.The results showed that the oils (patauá, pracaxi, bacaba, açaí, tucumã) had high levels of unsaturated fatty acids, especially oleic acid, which has good thermal stability, while the fats (cupuaçu, bacuri and tucumã) are composed of mainly by saturated fatty acids. The oxidative stability showed that at a temperature of 110 °C, pracaxi oil and cupuaçu fat presented the highest values, while bacaba oil presented a lower value, this low stability value indicates that this sample is more conducive to oxidation. Pracaxi oil showed the highest value for the ratio between hypocholesterolemic and hypercholesterolemic fatty acids (HH), indicating that it is more nutritionally adequate. The studies to predict the regularity of Amazonian oils and fats proposed in this work may contribute to simplifying the evaluation of the physicochemical properties of important regional oleaginous raw materials on which there are no studies, but with growing industrial interest in different areas, in addition of the food area.
Acesso aberto (Open Access)
Caracterização do amido de pupunha albina (Bactris gasipaes Kunth)
(Universidade Federal do Pará, 2024-02-07) ROSÁRIO, Rosely Carvalho do; PIRES, Márlia Barbosa; http://lattes.cnpq.br/0635360297333947; https://orcid.org/0000-0002-8237-1045; SANTOS, Orquídea Vasconcelos dos; http://lattes.cnpq.br/9446483074995655; https://orcid.org/0000-0001-5423-1945
A new variety of peach palm fruit from the Amazon region produces albino fruits possibly resulting from successive hybridizations that cause considerable differences in color and composition, exhibiting a high energy content for carbohydrates and a starch content that deserves to be investigated. Therefore, the objective of this study was to characterize albino peach palm starch, analyzing its nutritional and morphological composition, as well os its technological, thermal and pasting functional properties. The methodologies applied followed internationally accepted and recommended guidelines. Albino peach palm starch by aqueous isolation resulted in a yield of 17.34%, and a slightly yellowish white powder, with quality within that recommended by current national legislation, with its moisture content at 8.64%. The isolation of this starch provided effective physical and chemical characteristics for conservation (aw= 0.255, pH= 5.75) and good quality (ash = 0.12g/100g, proteins = 0.80g/100g, lipids = 1.0g/100g and total starch content = 89.01 g/100g). APA has small granules with type A crystalline and regular crystallinity value (24.40%), confirming the high content of amylopectin (86.70%) and very low content of amylose (13.30%), being classified as low amylose starch. APA granules were more resistant and less susceptible to breakage with prolonged heating and temperature increase. The technological and functional characteristics of albino peach palm starch showed a high gelatinization temperature (93.1°C), low maximum (921.33 cP) and final (1014 cP) viscosities, water and oil absorption capacity values (2.19 and 1.79 g/g) equivalents, a good gelling capacity and little loss of water when cooling and freezing the gel. It was concluded that the use of the fruit of the albino peach palm to isolate starch showed potentially applicable results to the food, textile, pharmaceutical and cosmetic industries, in addition to promoting the local appreciation of food and small Amazonian agricultural communities.
Acesso aberto (Open Access)
Caracterização dos sistemas de produção de leite quanto à qualidade higiênico-sanitária produzidos na agricultura familiar no nordeste paraense.
(Universidade Federal do Pará, 2018-03-29) OLIVEIRA, Priscila Santos da Conceição; LIMA, Consuelo Lúcia Sousa de; http://lattes.cnpq.br/2971385954203459
Milk is one of the most consumed and commercialized agricultural products in Brazil. This product has excellent nutritional characteristics for microbial proliferation, favoring the reduction in the quality of the dairy products produced. In addition to this productive highlight, milk is linked to family farming, which has low production due to inadequate or non-existent hygiene practices. The present study aimed to characterize the production, social and economic system of 20 family farmers in the Northeast of Para. In addition, to evaluate the influence of good hygienic practices on milking on the microbiological and physical-chemical quality of the milk in natura, in order to promote improvement in milk quality, generating a positive impact on the 20 properties through the adequacy of normative instruction 62 of MAPA, 2011. Evaluations were carried out based on a checklist and a semi-structured socioeconomic questionnaire in order to evaluate possible points of nonconformity in the properties and to characterize the main management techniques. Microbiological and physical-chemical analyzes were performed in raw milk before and after training in good practices, totaling 40 samples. In order to prove the influence of good practices on milk quality.
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)
Composição química, potencial antioxidante e antimicrobiano (in vitro) de extratos de geoprópolis de abelhas sem ferrão da Amazônia
(Universidade Federal do Pará, 2024-08-22) SILVA, Jonilson de Melo e; OLIVEIRA, Johnatt Allan Rocha de; http://lattes.cnpq.br/4620766111243038; MARTINS, Luiza Helena da Silva; http://lattes.cnpq.br/1164249317889517; https://orcid.org/0000-0003-1911-4502
The Amazon region presents a growing development of meliponiculture, the rational breeding of stingless bees. However, an essential product of this activity, geopropolis (a material made from resinous substances collected from plants to which bees add salivary secretions, wax, pollen, and earth), still has little value on the market due to the lack of information about its chemical composition and biological activities. The objective of this work is to study the geopropolis of stingless bees uruçu amarela (Melipona flavolineata), uruçu boca de renda (Melipona seminigra pernigra), and uruçu cinzenta (Melipona fasciculata), from the city of Terra Alta, located in the northeast of the state of Pará, regarding its chemical and mineral composition, determination of bioactive compounds, evaluation of antioxidant and antimicrobial properties and determination of the chromatographic profile (volatile compounds) of geopropolis ethanolic extracts obtained by agitation and sonication. The extracts from the optimal condition showed significant levels of total phenolic compounds, ranging from 5491.1 ± 446.33 to 13019.19 ± 186.56 mg EAG/100g, as well as the content of total flavonoids, which was between 190.31 ± 2.61 and 2498.02 ± 78.24 mg QE/100g. Regarding antioxidant activity, the sample with the best performance was yellow uruçu, which presented results of 1537.66 ± 19.52 μmol trolox eq./g, 1773.56 ± 6.52 μmol trolox eq./g and 7074, 41 ± 215.73 μmol ferrous sulfate eq./g, in the respective DPPH, ABTS and FRAP tests. Samples from uruçu Boca de renda and uruçu content presented antimicrobial action, with a minimum inhibitory concentration of 0.5 and 2 mg/mL, respectively. The analysis of volatile compounds demonstrated distinct chemical profiles between the samples since only 3 of the identified compounds (less than 4% of the total) were standard in all analyzed samples, suggesting that the geopropolis of the three species are made from different resin sources, despite the hives being located in the same environment. This exploratory research contributes essential information to the knowledge of the activities exhibited by the geopropolis produced in the Amazon region, helping in the progression of studies on stingless bees.
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)
Desenvolvimento de bebida fermentada análoga a kombucha, à base de inflorescências de jambu (acmella oleracea), e monitoramento de compostos bioativos
(Universidade Federal do Pará, 2023-12-19) BARROS, Vinícius Costa; BOTELHO, Vanessa Albres; http://lattes.cnpq.br/0992385832433182; CHISTÉ, Renan Campos; http://lattes.cnpq.br/0583058299891937; https://orcid.org/0000-0002-4549-3297
Kombucha is a fermented product that is increasingly expanding in relation to its consumption and the advancement of its research due to claims of its correlated health benefits, arising from its compounds generated in fermentation. Therefore, the following research aimed to corroborate these advances by developing an analogue to the fermented one using jambu (Acmella oleracea) as substrate, three formulations of the drink were developed in which in the first stage the pH values, total acidity were monitored for 7 days, total soluble solids, total and reducing sugars, antioxidant capacity, in addition to total phenolic compounds and flavonoids. After the product was ready, the same parameters, as in the first fermentation, were observed with the addition of volatile and fixed acidity, density, profile of phenolic compounds, microbiological and sensory analyses. The final products agreed with the regulated standard for kombuchas (IN 41 MAPA, Brazil), being microbiologically safe, and the formulation with 75% of jambu addition was the one with the highest sensorial preference as well as purchasing potential. In general, during the first fermentation, the formulation with 50% of jambu addition showed the best performance for phenolic compounds, flavonoids, and antioxidant capacity, requiring new future stability studies of these compounds to be available in ready-made products.
Acesso aberto (Open Access)
Desenvolvimento e avaliação de método rápido de análise semiquantitativa de cianeto total em derivados de mandioca
(Universidade Federal do Pará, 2018-03-23) CARDOSO, Tricia Noronha; ABREU, Laura Figueiredo; http://lattes.cnpq.br/9379947446021216; https://orcid.org/0000-0001-7286-4789; CARVALHO, Ana Vania; http://lattes.cnpq.br/7856575452724939
Because cassava is a raw material rich in cyanogenic compounds, and of safety issues, it is necessary to know the cyanide residues in the final products of flour, tucupi and maniva, since when ingested it can cause intoxication and development of chronic diseases. This work aimed to study a rapid and semi-quantitative method of analysis of total cyanide (kit) in cassava derivatives. Total cyanide determinations were carry out on roots and leaves of cassava, and their derived products (dry flour, tucupi and maniva) to evaluate the range of work to be proposed for the kit. The components of the kit were developed based on spectrophotometric methodology widely used in cassava research. It was established the storage time of the components of the developed kit and its validity from the figures of merit linearity, repeatability, working range and limit of detection. The total cyanide concentration in the cassava derivatives showed a distinct behavior among the samples, indicating a predominance of non - glycosidic cyanogenic compounds and linamarin residues. A suitable form of dehydrated and partially purified enzyme was developed from the precipitation of cassava weevil extract with ethanol solvent. The kit contains dropper bottles with buffer and alkaline solutions, color reagent, and enzyme on filter paper, stored in multilayer laminated packaging, which also sets up as the reaction vessel. This format was able to present visually differentiated color responses for the total cyanide concentration ranges in tucupi, flour and maniva samples. The stability study indicated that the kit should be stored under refrigeration and used in the maximum period of 30 days, for tucupi analysis, but with adjustments for the analysis of flour and maniva. The kit showed linearity between 1.03 and 3.97 μg of HCN per reaction package with correlation coefficient of 0.9898; working range between 5 and 100 ppm; relative standard deviation less than 3%; limit of detection of 5 ppm and recovery index between 88 and 94%.
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)
Efeito da adição de cera de abelha sobre as propriedades de filmes biodegradáveis elaborados com gelatina da pele de peixe
(Universidade Federal do Pará, 2022-08-22) MORAES, Vinicius Sidonio Vale; TEIXEIRA, Camilo Barroso; http://lattes.cnpq.br/7059706802675228; LOURENÇO, Lúcia de Fátima Henriques; http://lattes.cnpq.br/7365554949786769; https://orcid.org/0000-0001-5009-8235
Biodegradable films are defined as thin materials made from biomolecules, which act as a barrier against moisture, gases, light and mechanical injuries and, consequently, extend the shelf life of products. Biodegradable films made from biomolecules have gained visibility today, especially those made from gelatin extracted from fish skin. Despite having good optical and mechanical properties, they have high water vapor permeability (PVA). The addition of lipids such as beeswax is a good option to solve this problem. The objective of this work was the elaboration and characterization of a biodegradable film from yellow hake skin gelatin added with beeswax using sodium dodecyl sulfate (SDS) and stearic acid as a surfactant, aiming to improve the technological properties of the film. A complete factorial design was carried out to define the region with the best barrier and solubility of the films. The planning indicated the tendency of the concentrations for the best results of the characteristics of the film. Based on this, four films of film-forming solution containing 130 ml were prepared, the first being a Control film composed of 2% gelatin and 20% glycerol; second film (F1) composed of 2% gelatin, 20% glycerol, 5% beeswax, 80% SDS and 100% stearic acid; third film (F2) composed of 2% gelatin, 20% glycerol, 10% beeswax, 80% SDS and 100% stearic acid and the fourth film (F3) composed of 2% gelatin, 20% glycerol, 15% beeswax, 80% SDS and 100% stearic acid. The thickness of the films presented heterogeneous results due to the poor incorporation of the wax in the film matrix. Likewise, the addition of beeswax to the film did not have a positive influence on PVA because of the appearance of bubbles in the film-forming solution. However, all films obtained excellent solubility results, justified by the high hydrophobicity of the wax. The films obtained results that indicate opaque films with greenish yellow tones and high luminosity, with an excellent UV barrier, and can be used in foods with sensitivity to light. The microstructure analysis showed inhomogeneous films, with bi-layer-like structures, free spaces and cracks in the matrix.
Acesso aberto (Open Access)
Estudo cinético do processo fermentativo da seiva do tronco do óleo de palma (elaeis guineensis jacq.) para fins alimentícios
(Universidade Federal do Pará, 2018-04-09) VEIGA, Juliane Almeida; CORRÊA, Nádia Cristina Fernandes; http://lattes.cnpq.br/5763999772352165
The palm oil agro-industry generates millions of tons of solid biomass, among which trunks stand out. The sap contained in the central region has the highest concentration of fermentable sugars, making it an alternative raw material for the production of co products such as syrup, bioethanol and fermented alcoholic beverages. Therefore, the objective of the research was the kinetic study of the palm oil trunk sap for possible elaboration of a fermented beverage within the alcoholic standards required by Brazilian legislation. Introducing the raw sap: moisture content of 96.07%, ash content of 0.78%, pH 5.65, titratable acidity of 2.64%, specific mass of 1.02 g/cm3,°Brix of 8,03, concentration of total and reducing sugars of 55.89 g/L and 32.71g/L, respectively. To carry out the kinetics, the conditions of the crude sap were adjusted, through the process of evaporation by concentration, after treatment: 14 °Brix, pH 4.0, total and reducing sugars of 72.51 g/L and 55.89 g/L, varying only the concentration of initial cells (2.0, 3.5 and 5.0 g/L). A statistical analysis that there was no explained difference between the alcohol levels obtained. Presenting the inoculum with 5.0 g/L the best kinetic parameters for conversion of substrate into cells (YX/S 0.10), substrate into product (YP/S 0.41), efficiency (77.87%), productivity (1.72 g.L-1/h-1), μmax (0.07 h-1) and percentage of EtOH (3.50 °GL (% v/v))
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 da secagem da polpa de açaí pelo método de camada de espuma
(Universidade Federal do Pará, 2019-08-26) COLAÇO, Rafaella Maracajá Nunes; CORRÊA, Nádia Cristina Fernandes; http://lattes.cnpq.br/5763999772352165
The foam-mat drying was used as a dehydration method for açaí (Euterpe oleracea) pulp. Initially, the types of foaming agents were evaluated, also the influence of concentration’s and whipping times’ variation were evaluated for foam formation. By the choice of the best whipping time, the same diferente concentrations were used for the study of drying at different temperatures. For this, a prior study using a Central Composite Rotational Design were realized, which results have leading to a new experimental design to determine the best conditions of additive concentration and drying temperature, this time a 2² Factorial Design, with three central points were realized. The influence of the drying process conditions on the total anthocyanins, moisture, water activity and lightness (L*) was evaluated. Furthermore, an energy consumption study was performed based on the estimation of the equipment needed in the processes of obtaining dehydrated acai. This study allowed identify Emustab® as a good foaming agent for açaí foam, because it was produced foams with adequate density, expansion and stability for foam-mat drying. The drying temperature showed significative effects (p≤0,05) on total anthocyanins and moisture responses, whereas the effects statiscally significants (p≤0,05) for L* were concentration of additive and the interaction between concentration and temperature. The optimized condition was found by the desirability function. Still, estimation of energy consumption demonstrated the process of drying açai in foam layer as less energy intensive. Therefore, this study showed the feasibility of the technical and financial foam drying method for obtaining powdered açai pulp.
Acesso aberto (Open Access)
Estudo do processo de modificação química do amido na farinha de banana verde da variedade nanicão (Musa sp. AAA)
(Universidade Federal do Pará, 2014-06-27) NOGUEIRA, Francylla Milhomens; LOPES, Alessandra Santos; http://lattes.cnpq.br/8156697119235191; LOURENÇO, Lúcia de Fátima Henriques; http://lattes.cnpq.br/7365554949786769
Acesso aberto (Open Access)
Estudo dos atributos sensoriais das amêndoas de cacau (theobroma cacao l.) produzidas no estado do Pará
(Universidade Federal do Pará, 2022-02-11) SANTOS, Renato Meireles dos; SOUZA, Jesus Nazareno Silva de; http://lattes.cnpq.br/3640438725903079; https://orcid.org/0000-0002-0288-2321; LIMA, Consuelo Lúcia Sousa de; http://lattes.cnpq.br/2971385954203459; https://orcid.org/0000-0001-9432-8637
Cocoa (Theobroma cacao L.) has seeds that after processing become a valuable agricultural commodity in the world, in Brazil, the state of Pará is the main producer, accounting for more than 53% of national production. Although Pará is the largest producer, studies containing data on the sensory quality of almonds are not found in the literature, adding value and identity due to the characteristics of their origin. Thus, the aim of this study is to establish the sensory profile of almonds (nibs) from the main cocoa producing regions in the State of Pará (Lower Tocantins, Northeast, West, Southeast and Transamazônica). A questionnaire was applied to producers for fermentation and drying practices, followed by physical, physicochemical and bioactive compounds evaluation. The sensory profile was established from the Quantitative Descriptive Analysis (QDA), in addition to using an affective test to verify consumer preference for the chocolates produced. In the physical evaluation, the samples showed an acceptable commercial standard, however, with room for improvement in relation to seed fermentation. Among the physicochemical parameters (humidity, pH, acidity and water activity), moisture is within the established by legislation, the samples showed differences only in pH and acidity. The almonds from the Amazon mesoregions presented a very similar sensorial profile, it was possible to observe some differences in certain descriptors terms. It was verified that the post-harvest and/or processing parameters had no influence on the quality attributes of the cocoa beans.
Acesso aberto (Open Access)
Extração assistida por ultrassom de compostos bioativos das matrizes vegetais (eryngium foetidum L e talinum triangulare Jacq. Willd) do bioma amazônico utilizando solventes verdes
(Universidade Federal do Pará, 2021-10-19) SANTOS FILHO, Adilson Ferreira; RODRIGUES, Antonio Manoel da Cruz; http://lattes.cnpq.br/7524720020580309
The present work aims to evaluate the extraction parameters of bioactive compounds (phenolic compounds, flavonoids, carotenoids, chlorophyll, anthocyanins, betalains and saponins) and antioxidant capacity (DPPH and FRAP) of extracts using the probe assisted extraction method ultrasound with green solvents (ethanol and olein), in samples of chicória leaves (Eryngium foetidum L.) and cariru leaves (Talinum triangulare Jacq. Willd.). Five phases of extractions were evaluated, where in each phase the effect generated individually of each variable (ethanol concentration, proportion of ethanol and olein mixture, equipment range, temperature and extraction time) on bioactive compounds and antioxidant capacity were evaluated. In the 1st extraction phase, the results obtained in this presented work was high yields of biomolecules and antioxidant capacity in relation to the levels reported in the literature of chicória and cariru. The 70% ethanol concentration was the best extraction range for the samples. In the 2nd phase, the mixture ratio of 1:3 of ethanol: olein was the best range for capturing bioactive compounds for both samples. In the 3rd extraction phase (equipment range) when it varies from 50 to 80%, it was observed that depending on the compound of interest, the range used can vary, however, the range of 70% showed the highest yield in relation to bioactive compounds and antioxidant capacity for chicória and cariru. In relation to the 4th extraction phase (temperature) it allowed an increase in the capture of the compounds, being the ideal range of 30ºC for cariru and 40ºC for chicória. In the last extraction phase where the extraction time was evaluated, it was found that for both samples the period of 15 minutes provided high yields. Regarding the applied modeling, it can be highlighted that the kinetic model of mass transfer presents the possibility to predict the experimental data and to predict values of bioactive compounds with a confidence limit of 99%. By evaluating the oxidative stability of the extracts, it can be seen that the compounds present in the optimized extracts enabled a protective action, managing to extend the olein stability index from 8 hours to 13.68 hours in the case of cariru extract and 12.79 hours for chicory. 7