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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Obtenção e caracterização da farinha de castanha (Castanea spp.) e seu potencial de aplicação em produtos de panificação / Obtaining and characterization of chestnut (Castanea spp.) flour and its potential application in bakery products

Moreira, Ana Cláudia Varanda, 1985- 12 March 2014 (has links)
Orientador: Caroline Joy Steel / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T00:29:09Z (GMT). No. of bitstreams: 1 Moreira_AnaClaudiaVaranda_M.pdf: 2755890 bytes, checksum: d8415f5cd4d888a1a91888ab6d03b7bc (MD5) Previous issue date: 2014 / Resumo: Apesar de ser um produto comercialmente muito importante nos países europeus, principalmente em Portugal, e em alguns países asiáticos, tais como a Turquia e a China, a produção e comercialização dos diferentes tipos de castanha do gênero Castanea spp. em grande escala no Brasil está restrita a algumas regiões específicas, de clima mais ameno, a exemplo das regiões de maior altitude do estado de São Paulo, visto que ela é altamente perecível e suscetível à contaminação por fungos, o que requer estocagem sob temperaturas de refrigeração. Entretanto, sua farinha pode ser conservada por mais tempo à temperatura ambiente; além disso, esta possui alto teor de amido, tendo sido encontrado alto teor de amido resistente. Ainda, a farinha de castanha possui conteúdo significativo de proteínas e um baixo teor de lipídeos. No Brasil, a farinha de castanha não é encontrada comercialmente e a sua produção a partir das sementes colhidas ainda não foi amplamente estudada, nem a sua aplicação. Por conseguinte, o objetivo deste trabalho foi avaliar o melhor método de obtenção da farinha de castanha (Castanea spp.), bem como caracterizá-las com relação à sua composição centesimal, características reológicas, propriedades de pasta e teor de amido resistente. Para tanto, foram obtidas três amostras de farinha de castanha por diferentes métodos, avaliando-se a possibilidade de sua aplicação em produtos de panificação, mais especificamente, em bolo inglês e em biscoito tipo cookie. As 3 farinhas obtidas foram analisadas em sua composição centesimal, cor, fibra alimentar, amido resistente e análise reológica em blends com farinha de trigo. Os cookies e os bolos produzidos foram avaliados quanto ao teor de fibra alimentar e amido resistente, bem como quanto à textura, umidade e atividade de água ao longo do armazenamento. Quanto aos resultados, a farinha Integral apresentou 7,6+0,3% de umidade, 1,49+0,07% de lipídeos, 4,61+0,17% de proteínas, 2,03+0,08% de cinzas e 16,75+0,45% de fibra alimentar. Já a farinha Refinada possuiu 7,12+0,19% de umidade, 1,39+0,39% de lipídeos, 4,50+0,03% de proteínas, 2,23+0,03% de cinzas e 10,88+0,43% de fibra alimentar. A farinha Seca Inteira possuiu 7,49+0,07% de umidade, 1,25+0,13% de lipídeos, 4,05+0,15% de proteínas, 2,15+0,02% de cinzas e 11,93+0,27% de fibra alimentar. Os teores de fibra alimentar e amido resistente nos bolos elaborados com farinha de castanha foram significativamente maiores que os constatados na formulação controle e, durante a estocagem, houve pouca alteração nos teores de umidade e atividade de água dos bolos, enquanto que, no que diz respeito ao parâmetro "textura", observou-se um aumento significativo da firmeza entre os dias 5 e 10 de estocagem. Já os cookies elaborados com farinha de castanha obtiveram maiores teores de fibra alimentar e de amido resistente que o controle, além de maior espalhabilidade. Por fim, os bolos e biscoitos foram submetidos à análise sensorial de aceitação e intenção de compra, todos obtendo notas de aceitação entre 6 (gostei ligeiramente) e 7 (gostei moderadamente), o que denota grande potencial de aplicação da farinha de castanha em produtos de panificação / Abstract: Despite being a very important commercial product in European countries, especially in Portugal, and in some Asian countries, such as Turkey and China, production and trade of different varieties of chestnut genus Castanea spp. in large scale in Brazil is restricted to specific regions of milder weather, such as the ones with higher altitudes in the state of São Paulo. The chestnut is highly perishable and very susceptible to contamination by fungi, requiring storage at refrigeration temperatures. However, chestnut flour can be stored for a longer time at room temperature; furthermore, this flour has high starch content and it has been found to have high resistant starch content. Also, chestnut flour has significant protein content, and it has low lipid content. In Brazil, chestnut flour is not commercially produced and its production from harvested seeds has not been widely studied, neither its application. Therefore, the aim of this study was to evaluate the best method of obtaining chestnut (Castanea spp.) flour, as well as to characterize the chestnut flours as to their chemical composition, rheological properties, pasting properties and resistant starch content. Three samples of chestnut flour were obtained by different production methods. Finally, the possibility of applying the flour in bakery products was evaluated, more specifically, pound cakes and cookies, for the purpose of nutritional enrichment of the products. The 3 flours obtained were analyzed for their chemical composition, color, dietary fiber, resistant starch and rheological analyses in blends with wheat flour. Cookies and pound cakes produced were evaluated for dietary fiber and resistant starch as well as texture, moisture and water activity during storage and sensory analysis of acceptance and purchase intent was performed. Whole flour had 7.6+0.3% moisture, 1.49+0.07% fat, 4.61±0.17% protein, 2.03±0.08% ash and 16.75+0.45% dietary fiber. Refined flour had 7.12+0.19% moisture, 1.39 +0.39% fat, 4.50+0.03% protein, 2.23+0.03% ash and 10.88+0.43% dietary fiber. Dried Whole flour had 7.49+0.07% moisture, 1.25+0.13% fat, 4.05+0.15% protein, 2.15+0.02% ash and 11.93+0.27% dietary fiber. The levels of dietary fiber and resistant starch in the cakes elaborated with chestnut flour were significantly higher than in the control. During storage, there was little change in moisture content and water activity of the cakes, but firmness showed a significant increase between the 5th and the 10th day of storage. Cookies made with chestnut flour showed higher spreadability and higher dietary fiber and resistant starch contents than the control. Both cookies and cakes evaluated presented acceptance scores between 6 (like slightly) and 7 (like moderately) showing the great potential of application of chestnut flour in bakery products / Mestrado / Tecnologia de Alimentos / Mestra em Tecnologia de Alimentos
22

Folate, choline, betaine, resistant starch & dietary fiber in Swedish lentils : Effect of cultivar and growing conditions

Dürr, Julia January 2020 (has links)
Background: One key component in the development of sustainable farming and foodstuffs is to increase the cultivation of legumes, due to their environmental and health benefits. Legumes contain several essential vitamins and minerals, protein and fiber, but cultivation can be problematic due to their weak stem strength which results in loss of crops as a result of crop lodging and susceptibility to weed invasion. One possible solution is co-cultivation with cereal crops such as oats as they provide support and outcompete weed growth, however, it is still unknown if co-cultivation will affect the nutrient content of lentils. Aim: The thesis has two aims: first, to compare choline, betaine, folate, resistant starch and dietary fiber content in two different types of lentils: Gotland lentils and Anicia lentils; and second to examine if cocultivation with oats will affect the nutrient content of the two lentil types. Methods: Betaine and choline were analyzed through high pressure liquid chromatography-mass spectrometry (HPLC-MS) and folate through high pressure liquid chromatography with fluorometric/UV detection (HPLC-FL/UV). Resistant starch, non-resistant starch and dietary fiber were analyzed according to enzymatic assay kits by Megazyme. Results: Significant differences in nutrient content between Anicia and Gotland lentils were seen regarding resistant starch content, with Gotland showing a 50 % higher content. A significantly greater choline content was found in Anicia lentil samples that were co-cultivated with oats, showing approx. a 15 % higher choline content. Gotland lentils co-cultivated with oats showed a significantly greater choline, resistant starch and dietary fiber content by 15 %, 70 % and 10 %, respectively. Conclusions: There was no reported significant difference in choline, betaine, folate and dietary fiber content, but in resistant starch between the two lentil types, with Gotland lentil showing a higher resistant starch content. There appeared to be a positive effect of co-cultivation with oats since a significantly higher choline content in both lentil types co-cultivated with oats and a significant increase resistant starch and dietary fiber in Gotland lentils co-cultivated with oats was reported. This suggests that cocultivation can lead to an increase in nutritional content for some nutrients in Gotland and Anicia lentils. The dietary fiber analysis confirmed that legumes are a great source of fiber by one portion providing approx. half the recommended daily amount. Cultivation and consumption of lentils can give both environmental and health benefits. Further studies are needed to explore other pulses and effect on other nutrients. / Svenska ekologiska linser
23

Reactive Extrusion of Phosphate Cross-linked Resistant Pea Starches

Huo, Gang 27 April 2016 (has links)
The primary objectives of this study were to develop an effective reactive extrusion process to produce granular phosphorylated pea starches with enhanced enzyme resistance, and examine the effects of bulk phosphorylation conditions on the morphology, physicochemical and functional properties of extruded pea starch phosphates. Two types of commercially available pea starches (NutriPea and Meelunie) were chosen as the research subjects in this study with differing native resistance. A number of methods including optical microscopy, SEM, ICP-OES, Englyst method, DSC and rapid visco analysis (RVA) were used to characterize the morphology and properties of extruded pea starches. The effects of feed formulations and extrusion conditions on phosphorus incorporation and Englyst digestion profiles were examined systemically. The results showed that phosphorus content and digestion profiles were highly dependent on the feed moisture. Enzyme resistance did not positively correlate with phosphorus content for extruded pea starch phosphates in contrast to their counterparts prepared by conventional aqueous slurry. This was because extrusion processing can markedly increase the susceptibility of pea starch granules to enzymatic digestion. Lower feed moisture content (40%) gave lower phosphorus content, significantly lower RDS content, and higher SDS and/or RS content. Bulk phosphorylation in the extruder resulted in decreased RS2 content but increased RS4 content. Screw geometry with excessive mixing index was not desirable in terms of producing resistant starch. High screw speeds (150rpm and 200rpm) and low feed rate (1.02kg/h) brought about higher yields of SDS and RS in spite of lower phosphorus incorporation. Reactive extrusion of pea starches under optimized conditions achieved a significant but moderate increase either in RS content (from 18.67% to 22.57% for NutriPea) or in SDS content (from 37.18% to 42.23% for Meelunie) compared to their native counterparts. However, RS and SDS content could not be improved simultaneously at least based on these pea starches and the reactive extrusion processes in this study. The optical and SEM micrographs confirmed that the granule integrity was largely retained after optimized reactive extrusion process. DSC thermograms found no significant correlation between gelatinization characteristics and Englyst digestion profiles. Evidenced by RVA pasting profiles, NutriPea pea starch phosphates exhibited enhanced thermal and shear stability in comparison to their native counterpart. A novel foaming injection technology of cross-linking reagents solution was pioneeringly introduced to uniformly coat all starch particles at the lowest moisture level possible during the continuous production of granular NutriPea pea starch phosphates. Yet, the resulting phosphorus incorporation was much lower than expected and would require further studies. / Thesis / Master of Applied Science (MASc) / The Canadian food industry is increasingly interested in the potential to probe new avenues to produce enzyme-resistant food starches from pulses starches. Although extrusion cooking is commonly used for manufacturing cereals, snacks and other food products, no research has been reported on using an extruder to rapidly produce resistant pulse starches for functional food ingredients. This study aimed to develop an effective reactive extrusion process to produce phosphate cross-linked pea starches with enhanced enzyme resistance (i.e., increased slowly digestible starch (SDS) and resistant starch (RS) content ) based on an examination of the effects of reaction conditions on the properties of extrusion products. Two types of commercially available pea starches, NutriPea and Meelunie, were chosen as subjects of the research. The cross-linked pea starches under optimized conditions achieved a significant but moderate increase either in RS content (for NutriPea) or in SDS content (for Meelunie) compared to their native counterparts. However, RS and SDS content could not be improved simultaneously at least based on these pea starches and the reactive extrusion processes in this study.
24

Preparation of resistant starch with heat moisture treatment, acid modification, enzymatic modification, and epoxidation methods

You, Sangwon January 2018 (has links)
The main objectives of this study were to develop an effective process to produce modified pea starch with enhanced enzyme resistance property (RS) for food applications. The work compares a non-chemical method (heat moisture treatment) versus a chemical method (crosslinking). One type of commercial pea starch (Nutri-Pea) was used exclusively as the raw material in this study. A number of methods were used to characterize the properties of the modified pea starches: water solubility index (WSI), titration (conversion, iodine value), intrinsic viscosity, infrared spectroscopy (FT-IR), Englyst digestion method, total starch content, and rapid visco analysis (RVA). The effects of heat-moisture treatment on native pea starch and enzyme treated pea starch were examined. The results showed that the produced samples with both native starch and enzyme treated starch exhibited a sharp increase in intrinsic viscosity. Overall, this method was deemed undesirable and not extensively examined past preliminary evaluations. The main focus of the study was on a citric acid crosslinking reaction, chosen for its food compliancy. A temperature of 120 oC was considered ideal for the reaction. FT-IR confirmed the presence of the citric acid incorporation in the starch samples. To improve the extent of reaction, Butanetetracarboxylic acid (BTCA) was considered as a replacement for citric acid and its treated samples showed higher conversion and lower water solubility index than that of the citric acid treated samples. Sodium propionate (NaP) was also considered in the reaction, this time as a food-grade catalyst and found to have minor benefit in cross-linking. BTCA/NaP treated sample reached the highest conversion of the study (96.8±2.3 %) and the lowest WSI (13.1±2.0 %), which increased the RS fraction of the starch from 18% to 32%. The RVA pasting profiles examined were too low to compare due to the high degree of cross-linking. Further improvements to RS were sought by debranching the starch before acid crosslinking. A BTCA/NaP treated sample with enzyme treatment showed a low WSI (31.7±2.3 %) yet substantially higher RS fraction (80.81±0.18 %). Similar to the non-debranched acid modified samples, there were no significant RVA pasting results because of the high cross-linking. Finally, crosslinking with an epoxidized oil was tested to continue looking at food-grade solution yet possible increase the rate of the crosslinking reaction. The results of WSI indicated that this method had little influence on cross-linking, possibly due to the low epoxidation efficiency of vegetable oils, as determined by iodine value. / Thesis / Master of Applied Science (MASc)
25

Physicochemical and Sensory Properties of Resistant Starch-Based Cereal Products and Effects on Glycemic and Oxidative Stress Responses in Hispanic Women

Aigster, Annelisse 06 October 2009 (has links)
The incidence of type 2 diabetes is considered an epidemic in Western countries, and its prevalence is more common in the Hispanic population than in non-Hispanic whites. Postprandial hyperglycemia has been associated with oxidative stress (OS), thus; reducing postprandial glycemia and/or OS through dietary consumption of resistant starch (RS) may be one approach to help modulate glucose and insulin responses. The purpose of this study was twofold: 1) to evaluate the physicochemical and sensory properties of cereal food products supplemented with RS. 2) to compare the effects of a single ingestion of granola bars with high (~18 grams of RS) and low (~0 grams of RS) RS compositions on the postprandial glucose and insulin responses (n=14) and oxidative stress parameters (cellular glutathione peroxidase, F2- isoprostanes, and oxygen radical absorbance capacity) in Hispanic women (n=9). Granola bars and cereals were developed to provide 2 levels (10% and 15%) of RS; isocaloric (0% RS) control samples were prepared with readily digestible (high amylopectin) starch. Samples were stored for up to 4 weeks at 20 °C. Mean composition of the high RS granola bars was 6% protein, 15% moisture, and 18% lipid. RS levels slightly increased from 14 to 16 g/serving after 4 weeks of storage, supporting published research that RS increases with storage due to retrogradation and crystallization of amylose chains. Color became lighter as the level of RS increased (p<0.001). Granola bars containing RS were less brittle (p=0.0043) than control granola bars. Sensory results indicated granola bars/cereals were acceptable. RS-supplemented granola bars were then used for the evaluation of RS ingestion in humans. There was no difference in postprandial glucose and insulin responses after a single ingestion of a RS-supplemented (18 g) granola bar. No differences were found in the oxidative stress parameters measured. In a subgroup of subjects (n=9), a lower glucose response 30 minutes after RS consumption was found (p=0.0496). Thus, RS consumption may lower fluctuations in blood glucose, which may help manage glucose levels in individuals at risk of type 2 diabetes. Further studies of short term RS consumption are warranted to elucidate its benefits in glucose management. / Ph. D.
26

Produtos derivados de banana verde ('Musa' spp.) e sua influência na tolerância à glicose e na fermentação colônica / Unripe banana (Musa spp.) products and their influence over glucose tolerance and colonic fermentation

Cardenette, Giselli Helena Lima 09 October 2006 (has links)
Crescente ênfase vem sendo dada ao estudo e desenvolvimento de alimentos ricos em carboidratos não-disponíveis em virtude de seus benefícios já comprovados. O presente trabalho visou caracterizar carboidratos da banana verde e avaliar efeitos fisiológicos de seus carboidratos não-disponíveis sobre a tolerância à glicose, entre outros parâmetros relacionados a ela ou à saúde em geral. A massa de banana verde (MBV) (banana verde cozida com casca) e o amido de banana verde (ABV) (amido isolado) foram os principais produtos estudados. Foram realizados ensaios de curta duração em humanos e em ratos, e de média duração somente em ratos. Para a caracterização dos produtos e rações utilizados, foram avaliados principalmente os teores de amido resistente (AR), fibra alimentar (FA), fração indigerível (FI) e o perfil da fermentação in vitro. Os efeitos fisiológicos dos produtos e rações foram avaliados por curvas glicêmicas, teste de tolerância à glicose (TTG), perfil lipídico e de fermentabilidade in vivo. Os produtos de banana verde e as rações elaboradas com os mesmos apresentaram alto teor de carboidratos não-disponíveis, diferentes em quantidade e qualidade, mas com alta fermentabilidade, sinalizada pelo aumento da produção de ácidos graxos de cadeia curta (AGCC) e diminuição de pH na fermentação colônica in vitro ou in vivo. A ingestão de MBV ou ABV como primeira dieta, em ensaios de curta duração com ratos, afetou a glicemia pós-prandial de uma segunda dieta padrão, o que não foi observado com rações contendo tais produtos em menor proporção. Por outro lado, em 28 dias as rações contendo MBV ou ABV causaram menor secreção de insulina em ilhotas pancreáticas, o que possibilita poupar as células ß. Os resultados indicam que os produtos estudados têm grande potencial para serem utilizados na elaboração de alimentos destinados à prevenção de determinadas doenças crônicas não-transmissíveis, como diabetes tipo 2. / The study of unavailable carbohydrates has been of great concern due to their proven benefits to health. This work aimed to characterize carbohydrates of unripe bananas, as well as to evaluate physiological effects of their unavailable carbohydrates over glucose tolerance, among other parameters related to it or to individuals\' health in general. The unripe banana mass (MBV) (unripe banana cooked with peel) and the unripe banana starch (ABV) (isolated starch from the fruit in natura) were the main studied products. Short term assays were carried out with humans and rats, while medium term ones were realized with rats. In order to characterize the products and diets used in this work, several parameters were evaluated, such as quantifications of resistant starch (RS), dietary fiber (DF), indigestible fraction (IF) and the study of the in vitro fermentation profile. The physiological effects of the products and diets were evaluated through glycemic curves, glucose tolerance test (GTT), and lipidic and fermentative characteristics. The unripe banana products, as well as the diets elaborated with them, presented high amount of unavailable carbohydrates, in different quantity and quality, but all of them with high fermentative rates, signalized buy an increase in short chain fatty acids (SFCA) production and decrease in pH on colonic fermentation carried out in vivo or in vitro. In the short term assays, the MBV and ABV intakes affected the postprandial glycemic response to a following diet in rats. Similar effect was not noticed in medium term assays after the intake of diets containing unripe banana products in lower proportions for 28 days. On the other hand, in this medium term assays, rats diets containing MBV or ABV lead to lower insulin secretion in isolated pancreatic islets, which may preserve ß cells function. The results of this work point that the unripe banana products have great potential to be applied in special food elaboration aiming the prevention of some non-transmissible chronic diseases.
27

Macarrão instantâneo funcional obtido pelos processos de fritura convencional e a vácuo / Development of functional instant noodles using atmospheric and vacuum frying

Vernaza Leoro, Maria Gabriela 17 August 2018 (has links)
Orientador: Yoon Kil Chang / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-17T11:10:29Z (GMT). No. of bitstreams: 1 VernazaLeoro_MariaGabriela_D.pdf: 8287795 bytes, checksum: a64048a016fa41109e78ee329b64b6fb (MD5) Previous issue date: 2011 / Resumo: A demanda por produtos com melhor qualidade nutricional e funcional tem aumentado nos últimos anos. O mercado de alimentos funcionais está aumentando no Brasil apresentando um crescimento superior a 50 % desde 2002. A soja e seus derivados apresentam grande potencial no mercado de alimentos funcionais, especialmente devido à presença das isoflavonas e ao alto teor protéico. Por outro lado, o amido resistente, considerado como um componente da fibra alimentar, não é digerido pelas enzimas presentes no sistema digestóriio dos seres humanos, mas pode ser fermentado pelas bactérias presentes no cólon, produzindo ácidos graxos de cadeia curta, trazendo benefociios á saúde das pessoas. O mercado mundial de macarrão instantâneo vem crescendo a taxas relativamente altas, maior do que o índice apresentado por sua própria categoria (massas alimentícias). O macarrão instantâneo, por ser um produto frito, contém uma alta porcentagem de óleo. Atualmente existe uma grande preocupação relacionada à saúde e ao consumo de alimentos com alto teor de gordura. Por isso, existe a necessidade de desenvolver produtos com melhor valor nutricional e a importância na utilização de novas tecnologias. A fritura a vácuo é uma forma alternativa de cozimento, a qual aumenta a qualidade dos alimentos desidratados. O objetivo geral deste trabalho visou o desenvolvimento de macarrão instantâneo funcional pela adição de amido resistente e isolado protéico de soja obtidos pelos processos de fritura convencional e a vácuo. Para alcançar o objetivo geral, o trabalho foi realizado em 3 etapas: i) Estudo da adição de sal (0-3 %) e de goma guar (0-1,5 %) na produção de macarrão instantâneo obtido pelo processo de fritura convencional, otimizando-se a formulação através da Metodologia de Superfície de Resposta, para obter um produto com características tecnológicas adequadas (baixo teor de gordura e boa firmeza); ii) Estudo da adição de 10 % de três amidos resistentes comerciais diferentes (Hi Maize 260, Promitor e farinha de banana verde) para estudar as propriedades reológicas e escolher a melhor formulação para obtenção de macarrão instantâneo funcional obtido pelos processos de fritura convencional e a vácuo, visando-se a obtenção de um produto com baixo teor de gordura, boa textura e alto teor final de amido resistente, e por ótimo; iii) Estudo da adição de amido resistente tipo 3 (AR3) (0-16 %) e de isolado protéico de soja (0-16 %) na produção de macarrão instantâneo obtido pelos processos de fritura convencional e a vácuo, visando-se a otimização da formulação através da Metodologia de Superfície de Resposta, com intuito de obter um produto com melhores características tecnológicas (baixo teor de gordura e boa firmeza), funcionais e nutricionais (alto teor de fibra e de proteína). Na primeira etapa, os resultados mostraram que a adição de goma guar e sal à formulação de macarrão instantâneo alteraram as propriedades da massa e a qualidade do produto final. Os maiores valores de absorção de gordura e os menores valores de firmeza foram obtidos quando utilizados valores médios das duas variáveis, enquanto que os menores valores foram alcançados ao utilizar os níveis extremos, ou seja, altos níveis de uma variável e baixos da outra, ou vice versa. Analisando os resultados obtidos no delineamento central composto rotacional (DCCR) foi possível escolher uma formulação adequada para dar continuidade ao estudo. Portanto, foi escolhido como ponto ótimo uma formulação com 0,22 % de goma guar e 2 % de sal para obter macarrões instantâneos de boa qualidade, com um teor de gordura moderadamente mais baixo e uma firmeza intermediária. Na segunda etapa, as misturas de farinha de trigo com 10 % de Hi Maize (HM10) (AR2) e Promitor (Prom10) (AR3) n? afetaram significativamente as propriedades reológicas da massa, quando comparados com a mistura com 10 % de farinha de banana verde (Ban10) que alterou significativamente a estabilidade da massa e o indice de tolerância à mistura. Os macarrões instantâneos Prom10 apresentaram as melhores propriedades tecnológicas, sendo que foram obtidos os menores valores de absorção de gordura e os maiores valores de firmeza, quando comparados com os macarrões instantâneos HM10 e Ban10. De uma forma geral, as amostras obtidas pelo processo de fritura a vácuo apresentaram menor teor de gordura, quando comparados aos macarrões obtidos pelo processo de fritura convencional. Concluindo, foi possível obter macarrões instantâneos funcionais com as três formulações diferentes estudadas, pois as amostras apresentaram um teor de amido resistente maior que 3 %, podendo ser declarados como fonte de fibra pela legislação brasileira. Na terceira etapa, as superfícies de resposta mostraram que a adição de amido resistente AR3 e de isolado protéico de soja diminuiu a absorção de gordura quando utilizados os dois processos de fritura (convencional e vácuo). No entanto, os macarrões instantâneos obtidos pelo processo de fritura convencional apresentaram teores de gordura maiores (18,28 - 25,09 %) do que os obtidos pelo processo de fritura a vácuo (18,08 e 22,26 %). Em ambos os processos foi possível obter macarrões instantâneos com um teor de amido resistente significativo (acima de 3 % para todos os ensaios). Na analise de textura, os macarrões obtidos pelo processo de fritura convencional apresentaram uma firmeza maior do que os obtidos pelo processo de fritura a vácuo. As superfícies de resposta mostraram que a adição de amido resistente e de isolado protéico de soja afetaram a firmeza dos macarrões devido à diluição das proteínas do glúten, apresentando macarrões menos firmes. Finalmente, independente do processo de fritura utilizado, ao adicionar 12 % de AR3 e 8 % de IPS foi possível desenvolver um produto funcional com alto teor de fibras, alto teor de proteínas, presença de isoflavonas e com um perfil de aminoácidos melhorado / Abstract: A higher demand for products with better quality has increased the use of new ingredients and new technologies. Therefore, nowadays, there is a greater demand for functional foods. The functional food market is growing in Brazil, showing a 50 % increase since 2002. Soybean and its derivatives present good potential in the functional food market, especially due to the presence of isoflavones and the quality of its protein and polypeptides. On the other hand, resistant starch, considered as a food fiber component, is poorly digested by the enzymes present in the human digestive system, but can be fermented by bacteria present in the colon, producing short chain fatty acids that provide health benefits to the consumer. The world instant noodle market has been growing at relatively high rates, higher than the rate presented by the category as a whole. Since they are fried products, instant noodles contain high levels of residual oil. Currently, there is a considerable concern about health with respect to the consumption of high fat foods. Therefore, there is a need to develop products with enhanced nutritional value and the use of new technologies. The vacuum frying process is an alternative way of cooking, which increases the quality of dehydrated foods when compared to the conventional deep-frying process. The objective of the present work was to develop instant noodles with functional properties, using both conventional and vacuum frying processes to reduce oil absorption and hence caloric content, by the partial substitution of wheat flour with soy protein isolate and resistant starch. To achieve the overall objective, the work was divided into three stages: i) Study of the addition of salt (0-3 %) and guar gum (0-1.5 %) in the production of instant noodles optimizing the formulation by Response Surface Methodology to obtain a product with appropriate technological characteristics (low in fat and good texture); ii) Study of the addition of 10 % of three different commercial resistant starches, such as Hi Maize (HM) (RS2), Promitor (Prom) (RS3) and green banana flour (GBF) to analyze the rheological properties to produce the best formulation of functional instant noodles obtained by both conventional and vacuum frying, in order to obtain a product with adequate technological properties (low in fat, good texture and high content of resistant starch), and finally, iii) Study of the addition of type 3 resistant starch (RS3) (0-16 %) and soy protein isolate (0-16 %) in the production of instant noodles obtained by conventional and vacuum frying, in order to optimize the formulation by Response Surface Methodology with the objective of obtaining a product with adequate technological properties (low fat and good texture) and high nutritional value (high fiber and protein). In the first stage, the results showed that the addition of guar gum and salt to instant noodles formulation changed the properties of the dough and the final product quality. The highest values of fat absorption and the lowest values of firmness were obtained when intermediate levels of the two variables were used, whereas the lowest values were achieved when using the extreme levels, i.e. high levels of one variable and low of the another, or vice versa. Analyzing the results obtained from the central composite rotational design (CCRD) it was possible to choose a suitable formulation to continue the next stages. Therefore, the instant noodles considered optimum in this stage contained 0.22 % guar gum and 2 % salt, resulting in a product of good quality, with significant lower fat content and intermediate firmness. In the second stage, mixtures of wheat flour with 10 % Hi Miaze 260 (HM10) (RS2) and Promitor (Prom10) (RS3) did not significantly affect dough¿s rheological properties when compared to the mixture with 10 % green banana flour (Ban10), that changed drastically the dough stability and the mixing tolerance index. Prom10 noodles presented the best technological properties, obtaining the lowest values of fat absorption and the highest values of firmness. In general, samples obtained by the vacuum frying process had lower fat content, compared to the samples obtained by the conventional frying process. Using the three different formulations, it was possible to obtain functional instant noodles because all samples presented a resistant starch content higher than 3 %, being possible to be claimed as source of fiber according to the Brazilian Legislation. In the third stage, the response surfaces showed that the addition of both resistant starch and soy protein isolate decreased fat absorption when using both frying processes (conventional and vacuum). However, instant noodles obtained by the conventional frying process presented higher levels of fat than those obtained by vacuum frying. In both cases there was a decrease in resistant starch content. In the texture analysis, noodles obtained by the conventional frying process presented higher firmness values than those obtained with the vacuum frying process. The response surfaces showed that resistant starch and soy protein isolate addition affected the firmness of noodles because of the dilution of gluten proteins, showing noodles with lower firmness. In conclusion, regardless of the frying process used in this study, when added 12 % of RS3 and 8 % of soy protein isolate, it was possible to develop a functional product with high fiber content (close to 8 %), high protein content (close to 11 %), isoflavones and with an improved amino acid profile / Doutorado / Doutor em Tecnologia de Alimentos
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Produtos derivados de banana verde ('Musa' spp.) e sua influência na tolerância à glicose e na fermentação colônica / Unripe banana (Musa spp.) products and their influence over glucose tolerance and colonic fermentation

Giselli Helena Lima Cardenette 09 October 2006 (has links)
Crescente ênfase vem sendo dada ao estudo e desenvolvimento de alimentos ricos em carboidratos não-disponíveis em virtude de seus benefícios já comprovados. O presente trabalho visou caracterizar carboidratos da banana verde e avaliar efeitos fisiológicos de seus carboidratos não-disponíveis sobre a tolerância à glicose, entre outros parâmetros relacionados a ela ou à saúde em geral. A massa de banana verde (MBV) (banana verde cozida com casca) e o amido de banana verde (ABV) (amido isolado) foram os principais produtos estudados. Foram realizados ensaios de curta duração em humanos e em ratos, e de média duração somente em ratos. Para a caracterização dos produtos e rações utilizados, foram avaliados principalmente os teores de amido resistente (AR), fibra alimentar (FA), fração indigerível (FI) e o perfil da fermentação in vitro. Os efeitos fisiológicos dos produtos e rações foram avaliados por curvas glicêmicas, teste de tolerância à glicose (TTG), perfil lipídico e de fermentabilidade in vivo. Os produtos de banana verde e as rações elaboradas com os mesmos apresentaram alto teor de carboidratos não-disponíveis, diferentes em quantidade e qualidade, mas com alta fermentabilidade, sinalizada pelo aumento da produção de ácidos graxos de cadeia curta (AGCC) e diminuição de pH na fermentação colônica in vitro ou in vivo. A ingestão de MBV ou ABV como primeira dieta, em ensaios de curta duração com ratos, afetou a glicemia pós-prandial de uma segunda dieta padrão, o que não foi observado com rações contendo tais produtos em menor proporção. Por outro lado, em 28 dias as rações contendo MBV ou ABV causaram menor secreção de insulina em ilhotas pancreáticas, o que possibilita poupar as células ß. Os resultados indicam que os produtos estudados têm grande potencial para serem utilizados na elaboração de alimentos destinados à prevenção de determinadas doenças crônicas não-transmissíveis, como diabetes tipo 2. / The study of unavailable carbohydrates has been of great concern due to their proven benefits to health. This work aimed to characterize carbohydrates of unripe bananas, as well as to evaluate physiological effects of their unavailable carbohydrates over glucose tolerance, among other parameters related to it or to individuals\' health in general. The unripe banana mass (MBV) (unripe banana cooked with peel) and the unripe banana starch (ABV) (isolated starch from the fruit in natura) were the main studied products. Short term assays were carried out with humans and rats, while medium term ones were realized with rats. In order to characterize the products and diets used in this work, several parameters were evaluated, such as quantifications of resistant starch (RS), dietary fiber (DF), indigestible fraction (IF) and the study of the in vitro fermentation profile. The physiological effects of the products and diets were evaluated through glycemic curves, glucose tolerance test (GTT), and lipidic and fermentative characteristics. The unripe banana products, as well as the diets elaborated with them, presented high amount of unavailable carbohydrates, in different quantity and quality, but all of them with high fermentative rates, signalized buy an increase in short chain fatty acids (SFCA) production and decrease in pH on colonic fermentation carried out in vivo or in vitro. In the short term assays, the MBV and ABV intakes affected the postprandial glycemic response to a following diet in rats. Similar effect was not noticed in medium term assays after the intake of diets containing unripe banana products in lower proportions for 28 days. On the other hand, in this medium term assays, rats diets containing MBV or ABV lead to lower insulin secretion in isolated pancreatic islets, which may preserve ß cells function. The results of this work point that the unripe banana products have great potential to be applied in special food elaboration aiming the prevention of some non-transmissible chronic diseases.
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Aplicação de amidos resistentes como ingredientes extensores substitutos de gordura em produto cárneo emulsionado / The use of resistant starch as fat replacers extenders ingredients in emulsified meat products

Carraro, Carla Ivone, 1985 21 August 2018 (has links)
Orientador: Marise Aparecida Rodrigues Pollonio / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-21T13:23:32Z (GMT). No. of bitstreams: 1 Carraro_CarlaIvone_M.pdf: 1342581 bytes, checksum: 704953159961e17e7eccb8bbed399c09 (MD5) Previous issue date: 2012 / Resumo: As mudanças nas exigências dos consumidores e o aumento da competição global no mercado de alimentos fazem com que as indústrias de produtos cárneos adotem novas tecnologias de processamento e uso de novos ingredientes, para agregar valor, especialmente no atributo saúde. Neste contexto, os amidos resistentes são compostos, que apresentam propriedades semelhantes às fibras, exercendo a mesma função fisiológica, no entanto muito pouco estudados em produtos cárneos. O objetivo deste trabalho foi avaliar a utilização de amidos resistentes em produto cárneo emulsionado tipo mortadela com reduzido teor de gordura para a obtenção de um produto final com apelo saudável. Os amidos resistentes do tipo 2, 3 e 4 foram testados quanto à capacidade de retenção de água e apresentaram valores similares a outros extensores já utilizados. Na primeira etapa do trabalho, foi escolhido o amido resistente (conhecido pela sigla AR) tipo 3 para ser avaliado frente a três diferentes níveis de adição. Na sequência, foram realizados os ajustes de formulação e elaboradas duas formulações controle, seguidas de quatro substituições parciais e substituições totais com 2,5 e 5,0 % de AR. .As formulações: C1 (10% de gordura e 5% de fécula de mandioca), C2 (20% de gordura e 5% de fécula de mandioca), F2 (10% de gordura e 5% de AR tipo 3), F4 (10% de gordura e 5% de AR tipo 2) e F6 (10% de gordura e 5% de AR tipo 4) foram selecionadas para avaliação sensorial. As formulações com farinha de banana verde foram excluídas no teste preliminar de diferença de controle pela diferença de coloração e propriedades físico-químicas indesejadas resultantes no produto final. As amostras foram submetidas a testes sensoriais de aceitação: cego e informado e de diferença do controle. Na avaliação sensorial por diferença de controle foi observado que nos atributos de textura e sabor as amostras não apresentaram diferenças significativas e no atributo cor, a amostra C1 obteve notas mais altas que o controle C2,demonstrando que o produto com menor teor de gordura teve uma boa aceitação. As amostras F2, F4 e F6 não apresentaram diferença com relação ao controle C1, concluindo que a substituição da fécula de mandioca por amido resistente foi satisfatória. O teste cego de aceitação para os atributos: aparência, aroma e sabor não apresentaram diferenças significativas entre as amostras, sendo que o controle C1, obteve pontuação maior em relação ao controle C2. Nos atributos de textura e impressão global, as amostras F4 e F6 não apresentaram diferenças significativas e a amostra F2 obteve menor pontuação. No teste informado não houve mudança perceptível na avaliação dos consumidores, porém a amostra controle C2 teve uma aceitação melhor, demonstrando que o consumidor ainda não está preparado para o conceito de alimento com apelo saudável. Desta forma pode-se concluir que é possível reduzir a gordura de mortadelas sem prejudicar a composição físico-química, propriedades funcionais e sensoriais do produto através da utilização de amido resistente como ingrediente extensor / Abstract: Changes in consumer demand and the increase of competition in the global food market make meat product industries adopt new processing technologies and we use new ingredients to add value, especially in health attribute. In this context, the resistant starches are compounds that exhibit properties similar to fibers, with the same physiological function, however very little studied in meat products. The aim of this study was to evaluate the use of resistant starches in emulsified meat product as Bologna sausage with reduced fat to obtain a final product with healthy appeal. The resistant starches, type 2, 3 and 4 were tested for their ability to retain water with the same results of others extenders already used in meat products. In the first step, was chosen resistant starch (abbreviated as RS) type 3 to be evaluated against three different levels of addition. After, adjustments were made to formulate and elaborate: two control formulations, followed by four substitutions partial and total replacements with 2,5% and 5,0% of RS. These formulations were selected for sensory assessment: C1 (10% fat and 5% cassava starch), C2 (20% fat and 5% cassava starch), and formulations with starch replacement by resistant starch: F2 (10% fat and 5% RS Type 3), F4 (10% fat and 5% RS Type 2) and F6 (10% fat and 5% RS type 4). The formulations with green banana flour were excluded by difference from control, as the different colour and physicochemical properties resulting undesired final product. The samples were tested for sensory acceptance: blind and informed test and difference from the control. In sensory evaluation by difference from control was observed that the texture and flavor attributes of the samples showed no significant differences in the color attribute and the sample C1 was obtained higher scores than the control C2, demonstrating that the product with lower fat content had a good acceptance. The samples F2, F4 and F6 showed no difference compared to the control C1, concluding that the replacement of cassava starch by resistant starch was satisfactory. The blind acceptance for attributes: appearance, aroma and flavor showed no significant differences between the samples, and control C1, obtained higher scores than control C2. In texture attributes and overall impression, F4 and F6 samples showed no significant differences and F2 sample obtained lower scores. In reported test no noticeable change in the assessment of consumers, but the control sample C2 had a better acceptance, demonstrating that the consumer is not ready for the concept of meat products with healthy appeal. Thus it can be concluded that it is possible to reduce fat in Bologna sausage without impairing the physical and chemical composition, functional and sensory properties of the product through the use of resistant starch as an extender ingredient / Mestrado / Tecnologia de Alimentos / Mestra em Tecnologia de Alimentos
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Influência da adição de diferentes fontes de fibras (farinha de trigo de grão inteiro e amido resistente) e de transglutaminase nas características tecnológicas, estruturais e sensoriais de massas alimentícias / Influence of the addition of different sources of fibers (whole grain wheat flour and resistant starch) and transglutaminase on technological, structural and sensory characteristics of pasta

Jaekel, Leandra Zafalon 22 August 2018 (has links)
Orientador: Yoon Kil Chang / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-22T11:08:16Z (GMT). No. of bitstreams: 1 Jaekel_LeandraZafalon_D.pdf: 6646939 bytes, checksum: 22f384ec4204fdfd6cd400a411696f70 (MD5) Previous issue date: 2013 / Resumo: O interesse dos consumidores por alimentos com características funcionais tem aumentado nos últimos anos. A farinha de trigo de grão inteiro (FTGI) contém constituintes com efeitos benéficos a saúde (fibras, minerais, vitaminas, antioxidantes e aminoácidos). O amido resistente (AR) também tem sua contribuição à saúde, atuando como fibra alimentar. Massas alimentícias, cuja produção brasileira cresce a cada ano, constituem uma excelente forma de aplicação dessas matérias-primas. Contudo, a FTGI e o AR podem trazer prejuízos tecnológicos. A enzima transglutaminase (TG) mostra-se como alternativa a esse problema, pode atuar formando ligações cruzadas com a glutenina e a gliadina. O objetivo geral foi estudar o efeito de diferentes fontes de fibras (FTGI ou AR) e da transglutaminase nas características tecnológicas, estruturais e sensoriais de massas alimentícias tipo espaguete. O estudo foi desenvolvido em quatro artigos: 1°) estudar a influência da adição de FTGI (51 a 100 %) e TG (0 a 0,5 %) nas características reológicas, de cozimento, textura e solubilidade de proteínas dos espaguetes, através de um delineamento composto central rotacional (DCCR); 2°) estudar o efeito da TG (0,5 %) nas características de cozimento e textura, estruturais e sensoriais de espaguetes adicionados de 58 % de FTGI; 3°) estudar o efeito da adição de AR (0 a 20 %) e TG (0,2 a 1,0 %) nas características (citadas no 1°artigo) dos espaguetes, através de um DCCR; 4°) estudar o efeito da TG (1,0 %) nas características (citadas no 2° artigo) de espaguetes adicionados de 14 % de AR. No 1°) observou-se que a adição de FTGI e TG foi estatisticamente significativa (p<0,10) para o tempo de desenvolvimento da massa, índice de tolerância à mistura e cor (L*). Os produtos constituem fontes de fibras, pois contêm mais de 3 % de fibra alimentar no produto pronto para o consumo (Portaria SVS/MS nº 27, 13/01/1998). No 2°) verificou-se que a TG aumentou (p<0,05) a firmeza e a temperatura final de gelatinização; também observou-se seu efeito na estrutura do produto por microscopia eletrônica de varredura (MEV). A avaliação sensorial mostrou que o produto adicionado ou não de TG não diferiu estatisticamente (p<0,05) do controle quanto à textura e sabor, e a aparência foi melhor. Nos testes de aceitação e intenção de compra, a média dos espaguetes foi 7 e 4, que correspondem a "gostei moderadamente" e "provavelmente compraria", respectivamente. Além disso, as massas com adição de 58 % de FTGI são consideradas fonte de fibras e produtos e baixo índice glicêmico (aproximadamente 65 %). No 3°) AR e TG foram estatisticamente significativos (p<0,10) para cor, tempo ótimo de cozimento, aumento de peso, elasticidade e o teor de AR. Alguns dos produtos desenvolvidos foram fontes de fibra. No 4°) TG aumentou significativamente (p<0,05) a firmeza e elasticidade. A solubilidade proteica foi inferior no produto com TG para um tipo de solvente. O efeito da TG também foi observado através de MEV. Na avaliação sensorial, os espaguetes com ou sem TG não apresentaram diferença estatística para os parâmetros analisados através do teste de comparação múltipla, na aceitação e intenção de compra. A adição de 14 % de AR, além de caracterizar os produtos como fonte de fibras e de baixo índice glicêmico, possibilita a obtenção de produtos de qualidade tecnológica semelhante aos existentes no mercado / Abstract: The consumer interest in foods with better nutritional and functional characteristics is increasing in recent years. Whole-grain wheat flour (WGWF) contains many constituents with beneficial health effects (fiber, minerals, vitamins, natural antioxidants and amino acids). The resistant starch (RS) also contributes to human health once it presents similar effect of dietary fiber. Pasta, whose Brazilian production is increasing every year, consists of an excellent way of applying these raw materials. However, WGWF and RS may produce harmful effects during production process, since these components dilute the proteins forming the gluten in the product. The transglutaminase enzyme (TG) can act by forming cross links with the glutenin and gliadin, showing up as an alternative to this problem. The general objective was to develop spaghetti and study the effect of different sources of fiber (WGWF or RS) and transglutaminase on the technological, structural and sensory characteristics of the pasta. The study was conducted in four article: 1) the influence of adding WGWF and TG on texture, cooking characteristics and protein solubility of pasta using a randomized central composite design (RCCD), where the independent variables were WGWF (51 to 100%) and TG (0 to 0.5); 2) the effect of TG (0.5%) in texture, cooking, sensory and structural characteristics of pasta added 58% WGWF; 3) the effect of adding RS and TG on texture, cooking characteristics and protein solubility of pasta using a RCCD, where the independent variables were RS (0 to 20%) and TG (0.2 to 1.0); 4) the effect of TG (1.0%) on texture, cooking, structural and sensory characteristics of pasta containing 14% of RS. 1) The addition of TG and WGWF was statistically significant (p <0.10) in the dough development time, mixing tolerance index and color (L *). All formulations can be considered sources of fiber, since they contain more than 3% total dietary fiber. 2) We found that the addition of TG significantly increased (p <0.05) firmness and final gelatinization temperature and this effect was also observed in scanning electron microscopy (SEM). The sensory evaluationbased on the multiple comparison test showed that either pasta with TG addition orwithout the enzyme was not statistically different (p <0.05) than control sample with respect to texture and flavor. The appearance of these products was considered better than the control sample and did not differ from each other. Regarding the acceptance test and purchase intention, the average scores was 7 and 4, which correspond to "like moderately" and "probably buy" respectively. In addition, astacontaining 58% WGWF is considered source of fiber and low glycemic index food (about 65%). 3) RS and TG influenced the product quality, being statistically significant (p<0.10) for the color (L *, a *, b * and _E) optimum cooking time, increase weight, elasticity and RS content. It is worth mentioning any of the pasta developed in this study is source of dietary fiber. 4) We observed a significant effect (p <0.05) of TG on the characteristics of texture (firmness and resilience), once the product with added TG showed higher values than the product without TG addition. A significant effect was also observed on protein solubility, which was lower in the product containing TG when using a mixture of solvent. The effect of TG was also observed in scanning electron microscopy. In sensory evaluation, pasta with TG added or without the enzyme showed no statistical difference for theparameters studied by multiple comparison test, acceptance test and purchase intention. Besides characterizing the products as a source of fiber and low glycemic index, adding 14% of RS allows for obtaining competitive high-quality products / Doutorado / Tecnologia de Alimentos / Doutora em Tecnologia de Alimentos

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