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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Item 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.Item 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/0000-0002-6002-9425The 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.Item 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.Item 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/2311121099883170The 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.Item Acesso aberto (Open Access) Obtenção de um produto desidratado à base de tucupi, jambu e banana verde através do processo de Refractance Window(Universidade Federal do Pará, 2014-11-10) SANTOS, Paula Hellayne Costa dos; SILVA, Luiza Helena Meller da; http://lattes.cnpq.br/2311121099883170Given the immense diversity of fruits, vegetables and products developed in northern Brazil, tucupi, jambu and banana are notable because they are widely used, not only in culinary of Pará, but for several other purposes. Aiming to use these abundant products in the northern Brazil, the present work aimed at obtaining a dehydrated product based on tucupi, jambu and green banana, through the Refractance Window process. The formulations were dried at a temperature of 70 ° C, in a time of 50 min. Two formulations coded as FORM I and FORM II were dried. The initial moisture content of the formulations was 88% wb, and the values of final moisture content of the dehydrated product were 10% (for FORM I) and 9% (for FORM II). The drying time of the samples varied from one formulation to another, and the time was shorter for the drying of FORM II. The dried products had high water absorption capacity (2159.091 for FORM II) and (1666.667 for FORM I) and had an average oil absorption capacity. As to hygroscopicity, the products were considered little hygroscopic: 7.9 and 9.27 g H2O / g of sample for FORM I and FORM II, respectively. The dehydrated products showed significant content of phenols: 221.18 and 169.49 mg GAE / 100 g of sample for FORM I and FORM II, respectively. Regarding antioxidant capacity, the dehydrated products had higher antioxidant capacity by DPPH radical sequestration than the ABTS radical. For the results of color, the values (ΔE *) varied significantly for the dehydrated products with the same drying conditions. The shelf life was evaluated for 35 days and it was observed that the dried product of the Form I showed no change from seventh day, when evaluated by moisture gain, whereas FORM II showed variation during the entire period of storage . When the assessed parameter was the water activity, the FORM II did not change from the 14th day, while the FORM I changed only in twenty-first day of storage.