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BINDING OF COPPER, ZINC AND IRON BY SIX DIETARY FIBER SOURCESThompson, Sue Angele January 1980 (has links)
Six dietary fiber sources, wheat bran, corn bran, soy bran, oat hulls, rice bran, and cellulose were examined with regard to their abilities to bind copper, zinc, and iron. Their chemical composition, some of their physical properties, and their in vivo action on mineral status in tissues of chicks were investigated. Also, a comparison of the physicochemical properties of neutral detergent treated (NDF) and pepsin-pancreatin treated (EIR) residues was made. The release of endogenous copper, zinc, and iron from the fiber sources was pH dependent. Greater amounts of minerals were released into solution at pH 0.65 than into solution at pH 6.8. After a sequential treatment of pH 0.65 solution, neutralization, then pH 6.8 buffer, the mineral levels in the residues were similar to those remaining in the residues after the near neutral treatment. This indicated that the minerals were rebound after the pH of the solution was raised from acidic to near neutral. The amount of zinc in the residues from the sequential treatment correlated positively to protein and phytic acid contents and negatively to NDF and EIR contents. Neither copper nor iron showed any significant correlations. Hydrogen ion buffering capacities were determined for three preparations of the six fiber sources: (1) untreated, original material; (2) NDF-treated; and (3) EIR-treated materials. The buffering capacities were expressed as functions of the slopes of titration curves, where the smaller the slope, the greater the buffering capacity. The treated preparations had lower buffering capacities than did the untreated preparation. The treatments reduced the amounts of digestible/soluble components, especially protein in the fiber sources. Protein content was strongly correlated to buffering capacity for the untreated and the EIR-treated preparations but not for the NDF-treated preparation. Wheat bran, soy bran, oat hulls, and cellulose were subjected to NDF and EIR treatments, and the residues were used as column material for cation exchange experiments. A factorial experiment was performed using fibers by treatments by three solutions. The solutions were copper alone, zinc alone, and copper-zinc in combination. Cation exchange capacities (CEC) and protein contents were also determined. The CEC values for the residues from the two treatments for wheat bran and cellulose were similar but were very different for the soy bran (EIR-treated CEC was higher than NDF-treated) and oat hulls (NDF much greater than EIR). More mmoles of copper were bound than zinc whether presented alone or in equimolar combination. Protein content correlated to mmoles mineral bound for only the NDF-treated residues and only when the minerals were presented singly. These in vitro experiments demonstrated the intrinsic differences of the fiber sources. One fiber source may be beneficial to nutritional status while another may be detrimental. The fiber isolation technique produced residues with different compositions and different physical properties. Future biochemical investigations of dietary fiber must acknowledge the possible divergence from physiological reality which results from the isolation methodology. The chick feeding study used diets which had the fiber sources added to be equivalent to the addition of 6% dietary fiber (as NDF). At this level, all the fiber sources, except rice bran, resulted in adequate growth and adequate deposition of tissue minerals. The chicks on the rice bran diet had lowered feed intakes, significantly reduced growth and significantly lower tibia zinc, iron, and manganese levels. One factor in the rice bran diet, which may have influenced the status of the chicks, was its phytic acid content which was the highest of the fiber sources. This in vivo experiment again indicates the dissimilarity in effects of the dietary fiber sources.
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Nonstarch polysaccharide fractions of raw, processed and cooked carrotsKim, Sooyoun 18 May 1994 (has links)
The total and soluble nonstarch polysaccharide (NSP)
components of raw, processed (canned and frozen) and home-cooked
(boiled) Royal Chantenay carrots have been analyzed.
NSP fractions were characterized by separation and summation
of the monosaccharides resulting from acid hydrolysis of the
parent polysaccharides. Total NSP was primarily composed of
glucose, ~37%, and uronic acid, ~35%, containing
polysaccharides. Soluble NSP was composed of >50% uronic
acids. Processing and simulated home-cooking of raw carrots
resulted in an increase in the amount of NSP/unit dry
weight. Relative to raw carrots, cooking of canned product
resulted in the largest (~2-fold) increase in total and
soluble NSP/unit dry weight. Relative differences in NSP
were not as great when compared on a wet weight basis. / Graduation date: 1995
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Studies of high-fiber foods: I. The effect of a pinto bean diet on plasma cholesterol in hamsters. II. The effect of freeze-drying and heating during analysis on dietary fiber in cooked and raw carrotsPhillips, Katherine M. 14 October 2005 (has links)
The effect of a diet including cooked pinto beans on plasma total cholesterol in hamsters was investigated. The legume diet had 8.1% total fiber (1.0% soluble, 7.1% insoluble), all from pinto beans. Animals initially consumed a hypercholesterolemia-inducing diet. One control group remained on this feed for the duration of the study, and another consumed a diet with 8.6% total fiber (cellulose).
The pinto bean diet lowered plasma cholesterol significantly (13%) only in hypercholesterolemic hamsters (approximately 75% of the animals). When all animals were considered, the legume diet had no effect on cholesterol. Variability among hamsters in plasma cholesterol levels and changes was large. Results indicate the importance of including only hypercholesterolemic animals in studies of dietary modifications to decrease blood cholesterol and also that a large sample size may be required to detect significant effects.
Soluble and insoluble dietary fiber in raw and cooked carrots were measured by a typical enzymatic-gravimetric procedure. Analyses were done with and without freeze-drying and the starch gelatinization treatment (heating 1.25 hrs at 121°C). The gelatinization procedure caused a 3- to 5-fold increase in soluble fiber. In general, insoluble fiber decreased in the same proportion as the soluble fraction increased, suggesting a conversion of the former to the latter. The differences were greatest for cooked carrots and freeze-dried raw carrots. Compositional analyses indicated that heating increased arabinose, galactose, and uronic acids in soluble fiber fractions.
Cooked carrots had 3-9% more soluble fiber than raw carrots, with the difference being greater when the analysis included the gelatinization procedure. However, freeze-dried raw samples analyzed with gelatinization had the same level of soluble fiber (ca. 10%) as their boiled counterpart, suggesting an interaction between freeze-drying and the heat treatment in raw carrots.
Freeze-drying and heating to gelatinize starch are an integral part of many standard dietary fiber methods. Results of the present study suggest these treatments may mask differences between the amount of fiber in cooked and raw foods, and that dietary fiber values may not accurately represent the level of this component in foods as they are eaten. The results also raise the possibility of increasing soluble fiber by cooking modifications. / Ph. D.
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Sensory and dietary quality of fiber-beef blendsKatzir, Irena 24 July 2012 (has links)
Recently, there has been an increased interest in manufacturing high fiber Foods. Beef patties containing 1% Lupran (sweet lupin bran flour), 2% barley and 3% of both fibers (1% Lu + 2% Ba) and a control all-beef pattie were manufactured and comparatively evaluated by visual and sensory panels. Hypocholesterolemic effects were tested by in vivo studies. Rats were fed diets containing meat or meat-blends as the sole source of protein, fat, fiber and cholesterol. All the diets were isocaloric. At the point of purchase, the meat blends were different (P < 0.05) from the in their apparent amount exudate, fat to lean ratio and integrity. Less significant was the difference in color, both visual and objective, with the beef-barley blend tending to be darker and the beef-lupran product tending to be brighter within 14 days oF storage. The sensory panel scored meat-blends as significantly less beefy, more beany and grainy (P> 0.05). The grainy flavor of barley was especially detectable. Mouthfeel was not significantly altered (P> 0.05) but there was a tendency for the panel to score the barley blend as dryer and tougher than the control. However, these results were not confirmed by objective measurements. Cooking losses and quantity of measured exudate For meat blends were similar to the control. Neither lupran nor barley had a significant antioxidative effect. The meat blend with 3% fiber lowered the LDL fraction in rats relative to that of rats on control diets. However, the amount of added fiber was too low to significantly affect serum or liver cholesterol. / Master of Science
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Effects of different pineapple dietary fibres on the quality parameters and cost of beef species sausageTshalibe, Prince January 2014 (has links)
Thesis presented in partial fulfillment of the requirements for the degree
of
Master of Technology (Food Technology)
Department of Food Technology
Faculty of Applied Sciences
Cape Peninsula University of Technology / The nutrient profile of meat and meat products make them a major protein and minerals source for non- vegetarian human beings. However, their high fat content and the saturated fatty acid profile associate them with increased risk of lifestyle diseases and occurrences of cancers. Researchers have focused on fat replacement and fatty acid profile modification without compromising the physico-chemical and sensory characteristics of meat products. Leaner ingredients are expensive hence the use of low/non-calorie adding ingredients such as water, vegetable oils and oat bran. In this study, three pineapple dietary fibres (PDF), NSP 60, NSP 100 and NSP 200 with water binding capacities (WBC) of 1: 8; 1: 7.4; 1: 7.8 (g/g), respectively, were assessed for their WBC in species sausage at levels 0%, 0.5%, 1.0% and 1.5%. Water was added in accordance to the specific WBC capacity of the fibres, replacing pork back fat. The WBC of the fibre in the meat emulsion was assessed by extracting the loosely bound fluid by centrifugation. Fibres NSP 100 and NSP 200 proved to be of better water binding than NSP 60 which had the highest total expressible fluid (TEF) at all levels. Although differing significantly in WBC at all levels, all the fibres excellently bound water at 1% level. The three PDF (at 1% level) were then assessed with regard to chemical, physical, and textural attributes in species sausage. Proximate analysis showed that the control sausages (no fibre), differed significantly from the sausages containing PDF. Emulsion stability analysis was based on TEF, cooking loss and purge. Sausages containing NSP 200 PDF did not significantly differ to the control in terms of TEF and cooking loss. Sausages containing NSP 100 had the lowest cooking loss although not significantly different to the control and NSP 200 containing sausages. NSP 60 PDF performed significantly poorly in terms of TEF and cooking loss. The control had a significantly lower purge comparing to sausages containing which were not different. The pH value of the control was significantly higher than the samples containing fibres which also differed from each other. Inclusion of fibre in the species resulted in a significant increase in lightness, hue and chroma as compared to the control. Textural parameters for the control were significantly higher than the fibre containing sausages, except for cohesiveness which was similar for all sausages. This study concluded that NSP 100 could be the most suitable for use in species sausage, followed by the NSP 200 and lastly the NSP 60. Addition of PDF, in combination with water to a species sausage can be a viable way of cutting costs since the formulation cost of all the fibre containing sausages was lower in comparison to the control. Fibre and water addition can be a positive means of reducing the lipid fraction in sausages and other meat products, increasing the dietary fibre component and hence improving the health status of meat product consumers.
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Adição de oat fiber em produto cárneo reestruturado empanado de frangoFiorentin, Cristiane 06 June 2014 (has links)
Nos últimos anos tem-se verificado uma mudança no estilo de vida da população em virtude das facilidades encontradas para aquisição de alimentos no mercado, o que tem provocado um menor consumo de alimentos naturais e consequentemente diminuindo o consumo de alimentos com fonte de fibra alimentar. O objetivo desse projeto foi desenvolver um produto cárneo reestruturado empanado de frango adicionado de oat fiber, avaliando as características tecnológicas da fibra insolúvel, elaborar formulações com diferentes concentrações de oat fiber, determinar a composição proximal, cor, força de cisalhamento, microscopia óptica e analise sensorial das diferentes formulações. A caracterização do oat fiber demonstrou que a distribuição granulométrica correspondeu entre 38 e 75µm. A capacidade de retenção de água (CRA) do oat fiber resultou em 3,16g de água por grama de amostra e a capacidade de retenção de óleo (CRO) correspondeu 2,90 g de óleo por grama de amostra. O resultado da composição proximal da oat fiber foi de 9,88% de umidade, 3,39% de matéria mineral, 0,60% de lipídios, 3,06% de proteínas e 83,12% de fibra alimentar. Para a composição proximal dos empanados de frango elaborados com diferentes concentrações de oat fiber (3%, 4,5% e 6%) observou-se que o aumento da adição de fibra provocou uma diminuição nos teores de proteína e umidade, sendo que ocorreu o inverso para os teores de lipídios e matéria mineral, havendo diferença significativa (p<0,05) nas análises de umidade, matéria mineral e proteínas. O conteúdo de fibra alimentar no empanado de frango acompanhou o percentual de oat fiber adicionado nas formulações de 3% e 4,5%, porém a formulação de 6% não correspondeu à porcentagem adicionada, mas manteve-se com o maior índice de fibra alimentar. Todas as formulações poderiam receber na rotulagem o atributo fonte de fibras, segundo a legislação brasileira. Na análise de cor houve diferença significativa (p<0,05) entre as amostras analisadas para os parâmetros de L* e b*, entretanto não houve diferença significativa (p>0,05) para o parâmetro a*. Na análise de força de cisalhamento não houve diferença significativa entre as amostras (p>0,05). Na microscopia óptica, pode verificar que houve uma tendência da gordura se ligar com a fibra vegetal. A análise sensorial demonstrou que as três formulações são iguais entre si, sendo que não foram observadas diferenças significativas (p>0,05) para os atributos de cor, sabor e textura, no entanto, atributo suculência houve diferença significativa (p<0,05) entre as amostras. Todas as formulações apresentaram índices de interesse de compra. Esse trabalho demonstrou ser possível elaborar formulações de produtos reestruturados com bom comportamento diante da adição de fibra insolúvel, com boa aceitação sensorial e oferecendo para os consumidores um produto com fonte alternativa de fibras. / In recent years there has been a change in the life style of the population because of the facilities found to purchase food in the market, which has led to lower consumption of natural foods and consequently decreasing the consumption of foods with a source of dietary fiber. The project goal was to developed a restructured meat product breaded chicken add oat fiber, assessing the technological characteristics of insoluble fiber, develop formulations with different concentrations of oat fiber, determine the proximate composition, color, shear force, optical microscopy and sensory analysis of different formulations. The characterization of oat fiber showed that the particle size distribution corresponded between 38 and 75µm . The water holding capacity (WHC) of oat fiber resulted in 3.16 g of water per gram of sample and oil retention capacity (ORC) corresponded to 2.90 g oil per gram of sample. The result of the proximate composition of oat fiber was 9.88 % moisture, 3.39 % of ash, 0.60 % fat, 3.06 % protein and 83.12 % dietary fiber. For Proximal composition of breaded chicken made with different concentrations of oat fiber (3% , 4.5% and 6%) it was observed that increasing the addition of fiber resulted in a decrease in the protein and moisture , and was the inverse to the levels of lipids and mineral matter, significant difference (p<0.05) in the analysis of moisture, ash and protein . The content of dietary fiber in chicken fingers accompanied the percentage of added oat fiber in the formulation of 3 % and 4.5 %, but the formulation of 6 % did not match the percentage added, but remained with the highest fiber intake. All formulations could receive in labeling the attribute source of fiber, according to Brazilian law. In the analysis of color was no significant difference (p<0.05) between the samples analyzed for parameters L * and b *, however there was no significant difference (p>0.05) for the parameter a *. In the analysis of shear force no significant difference between samples (p>0.05). In optical microscopy, can verify that there was tendency of fat to bind with fiber Sensory analysis showed that the three formulations are equal, and there was no significant difference (p>0.05) for the attributes of color, taste and texture, however, juiciness attribute significant difference (p<0 05) between the samples. All formulations showed rates of buying interest. This work has proved possible to develop product formulations restructured with good behavior before the addition of insoluble fiber, with good acceptability to consumers and offering a product with an alternative source of fiber.
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Defining effective fiber content of dairy rationsMaddox, Terry L. January 1982 (has links)
Cottonseed hulls (CSH), chopped orchardgrass (OG) or alfalfa (ALF) hays were added to corn silage-based rations to determine effects on dry matter intake (DMI), nitrogen balance (NB), rumen volatile fatty acids (VFA), and rumen fluid (RFD) and solids (RSD) dilution rates. DMI was highest for added fiber rations and higher for CSH than hay rations. Digestibility of DM was depressed for added fiber rations with lowest for CSH. Most favorable NB was for CSH rations. Rumen VFA were not altered by fiber additions. Highest RFD was for 0% rations and lowest for 9% rations, however CSH had greatest positive influence on RFD. RSD trend was similar to that for RFD.
In Experiment II, 4 corn silage-based rations containing 9% OG, ALF, or CSH plus a Control (9% OG) were compared for effect on DMI, rumen VFA, chewing time (CT), RSD, and RFD. Ration density decreased with OG and ALF whereas CSH had no effect compared to Control. DMI was higher for CSH compared to OG and ALF. Total CT (min/d) and Roughage Value Index (CT/kg DMI) were reduced for ALF compared to OG. Total VFA were lower for added fiber rations compared to Control. Acetate:propionate (APR) and non-glucogenic (NGR) ratio were not affected by fiber additions. RFD was reduced for ALF compared to OG whereas CSH was higher than OG and ALF. Reduced RFD was associated with reduced total CT for ALF. RSD was not affected by fiber additions.
Chopped OG was supplemented at 0, 9, or 18% of ration DM in a finely chopped corn silage-based ration. Analysis of covariance was performed using 18 lactating Holsteins. Ration density decreased with each increment of OG. DMI was highest for 18% OG ration. Cows on 0% showed decreased DMI whereas cows on 9 and 18% rations increased DMI from covariate period. Rumen acetate, APR and NGR increased while propionate and total VFA decreased with increasing OG. RFD and RSD increased with increasing OG supplementation.
Response to 9 and 18% supplementation of OG, ALF, or CSH to corn silage-based rations appears to follow similar pattern as when all-forage rations were compared to all-concentrate rations for lactating dairy cows. A more quantitative evaluation of physical form is needed for dairy rations and feedstuffs leading to an acceptable routine evaluation procedure. / Ph. D.
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Desenvolvimento de drageado de soja [Glycine max (L.)] com cobertura crocante e salgada / Development soy drageado [Glycine max (l.)] with coverage and crispy saltSchena, Deivid Padilha 06 September 2016 (has links)
O consumo de produtos derivados de soja tem aumentado no Brasil levando à busca por melhoria em características sensoriais e diversidade de produtos. A soja é considerada um alimento funcional, pois contém isoflavonas, composto que auxilia na diminuição do risco de algumas doenças, principalmente ligadas ao câncer e doenças cardiovasculares, responsáveis pela maioria de mortes no mundo. A população tem pouca aceitação a produtos considerados funcionais, principalmente quando sensorialmente não é agradável. Com isso, o objetivo desse trabalho foi desenvolver um drageado de soja com cobertura crocante e salgada. Nos testes preliminares, definiu-se três formulações, formulação 1, com adição de 5 % de farinha de aveia, formulação 2 com 15 % de farinha de aveia e formulação 3 com 25 % de farinha de aveia. Os drageados foram avaliados quanto à composição proximal, análises microbiológicas, aceitação sensorial e de textura. Nas três formulações, não houve diferença significativa na composição proximal, indicando valores menores para lipídios, quando comparado a produtos comerciais. Para fibras alimentares, o produto desenvolvido obteve valores altos quando comparado a produtos à base de soja e principalmente a soja em grãos, com destaque para as formulações 2 e 3. O resultado para fibras alimentares apresentou valores acima do esperado, onde na legislação brasileira o produto para ser considerado com alto teor de fibras e alegação funcional necessita conter no mínimo 6 %, onde na formulação 3 obteve o valor de 14,5 %, sendo o teor de fibras insolúveis mais expressivo. Os resultados das análises microbiológicas comprovaram que o produto desenvolvido se enquadra na legislação brasileira, sendo assim não oferece risco à saúde do consumidor. As análises sensoriais dos drageados indicaram que o produto teve boa aceitação em cor e textura, obtendo notas de “gostei muito” a “moderadamente” e para sabor e aceitação global de “gostei” a “gostei moderadamente”. No índice de aceitabilidade, indicaram média acima de 70 %, principalmente na formulação 2, onde obteve o maior índice na média, 74,5 %. A análise de textura instrumental dos drageados não apresentou diferença entre as formulações avaliadas e pelos valores obtidos o produto desenvolvido apresentou menor dureza quando comparado ao produto comercial, o amendoim do tipo japonês. / O Consumption of soy products has increased in Brazil, leading to improvements in sensorial characteristics and product diversity. Soy is a food for animals, a product for human consumption, a product for health and a health system. The population has little acceptance of functional products, especially when sensory is not pleasant. With this, the objective of the work was elaborated based on coverage with food and salt coverage. In the preliminary tests, three formulations, formulation 1, with addition of 5% oat flour, formulation 2 with 15% oat flour and formulation 3 with 25% oat flour were defined. The dragees were on proximal composition, microbiological analyzes, sensory and texture acceptance. In the three formulations, there was no significant difference in the proximal composition, indicating lower lipid values when compared to commercial products. For the dietary fiber, the developed product obtained high values when compared to products based on soybeans and mainly soybeans in grains, with emphasis on formulations 2 and 3. The result for the dietary fibers had values higher than expected, where in Brazilian legislation Product to be assisted with high fiber content and functional claim needs to contain at least 6%, where formulation 3 obtained the value of 14.5%, and the content of insoluble fibers more expressive. The results of the microbiological analyzes proved that the product was developed and framed in the Brazilian legislation. As sensory analysis of the dragees indicate that the product had good acceptance in color and texture, obtaining notes of "I liked" a "moderately" and for overall taste and acceptance of "liked" a "moderately liked". In the index of acceptability, they indicated a mean above 70%, mainly in formulation 2, where it obtained the highest index in the average, 74.5%. The instrumental texture analysis of the dragees showed no differences between the formulations evaluated and the values obtained in the product developed during the comparison period when the product is marketed or japanese type peanuts.
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Desenvolvimento de drageado de soja [Glycine max (L.)] com cobertura crocante e salgada / Development soy drageado [Glycine max (l.)] with coverage and crispy saltSchena, Deivid Padilha 06 September 2016 (has links)
O consumo de produtos derivados de soja tem aumentado no Brasil levando à busca por melhoria em características sensoriais e diversidade de produtos. A soja é considerada um alimento funcional, pois contém isoflavonas, composto que auxilia na diminuição do risco de algumas doenças, principalmente ligadas ao câncer e doenças cardiovasculares, responsáveis pela maioria de mortes no mundo. A população tem pouca aceitação a produtos considerados funcionais, principalmente quando sensorialmente não é agradável. Com isso, o objetivo desse trabalho foi desenvolver um drageado de soja com cobertura crocante e salgada. Nos testes preliminares, definiu-se três formulações, formulação 1, com adição de 5 % de farinha de aveia, formulação 2 com 15 % de farinha de aveia e formulação 3 com 25 % de farinha de aveia. Os drageados foram avaliados quanto à composição proximal, análises microbiológicas, aceitação sensorial e de textura. Nas três formulações, não houve diferença significativa na composição proximal, indicando valores menores para lipídios, quando comparado a produtos comerciais. Para fibras alimentares, o produto desenvolvido obteve valores altos quando comparado a produtos à base de soja e principalmente a soja em grãos, com destaque para as formulações 2 e 3. O resultado para fibras alimentares apresentou valores acima do esperado, onde na legislação brasileira o produto para ser considerado com alto teor de fibras e alegação funcional necessita conter no mínimo 6 %, onde na formulação 3 obteve o valor de 14,5 %, sendo o teor de fibras insolúveis mais expressivo. Os resultados das análises microbiológicas comprovaram que o produto desenvolvido se enquadra na legislação brasileira, sendo assim não oferece risco à saúde do consumidor. As análises sensoriais dos drageados indicaram que o produto teve boa aceitação em cor e textura, obtendo notas de “gostei muito” a “moderadamente” e para sabor e aceitação global de “gostei” a “gostei moderadamente”. No índice de aceitabilidade, indicaram média acima de 70 %, principalmente na formulação 2, onde obteve o maior índice na média, 74,5 %. A análise de textura instrumental dos drageados não apresentou diferença entre as formulações avaliadas e pelos valores obtidos o produto desenvolvido apresentou menor dureza quando comparado ao produto comercial, o amendoim do tipo japonês. / O Consumption of soy products has increased in Brazil, leading to improvements in sensorial characteristics and product diversity. Soy is a food for animals, a product for human consumption, a product for health and a health system. The population has little acceptance of functional products, especially when sensory is not pleasant. With this, the objective of the work was elaborated based on coverage with food and salt coverage. In the preliminary tests, three formulations, formulation 1, with addition of 5% oat flour, formulation 2 with 15% oat flour and formulation 3 with 25% oat flour were defined. The dragees were on proximal composition, microbiological analyzes, sensory and texture acceptance. In the three formulations, there was no significant difference in the proximal composition, indicating lower lipid values when compared to commercial products. For the dietary fiber, the developed product obtained high values when compared to products based on soybeans and mainly soybeans in grains, with emphasis on formulations 2 and 3. The result for the dietary fibers had values higher than expected, where in Brazilian legislation Product to be assisted with high fiber content and functional claim needs to contain at least 6%, where formulation 3 obtained the value of 14.5%, and the content of insoluble fibers more expressive. The results of the microbiological analyzes proved that the product was developed and framed in the Brazilian legislation. As sensory analysis of the dragees indicate that the product had good acceptance in color and texture, obtaining notes of "I liked" a "moderately" and for overall taste and acceptance of "liked" a "moderately liked". In the index of acceptability, they indicated a mean above 70%, mainly in formulation 2, where it obtained the highest index in the average, 74.5%. The instrumental texture analysis of the dragees showed no differences between the formulations evaluated and the values obtained in the product developed during the comparison period when the product is marketed or japanese type peanuts.
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Development of antioxidant dietary fibers from wine grape pomace and their applications as functional food ingredientsTseng, Angela Y. 18 December 2012 (has links)
Wine grape pomace (WGP), the byproduct from winemaking, is a good source of polyphenols and dietary fibers, and may be utilized as antioxidant dietary fibers (ADF) for food applications. The objectives of this thesis research were to first determine the phenolic compounds, antioxidant and antimicrobial activities in red WGP under different drying processes for long-term storage, and to further evaluate the feasibility of using WGP as a functional food ingredient in yogurt and salad dressing for enhancing the nutritional value and improving storability of the products.
Two types of WGP samples, pomace containing seeds and skins (P) and pomace with skins only (S) from Pinot Noir (PN) and Merlot (M) were studied. Samples were subjected to four different drying conditions: 40 °C conventional and vacuum oven, 25 °C ambient air and freeze dry. Total phenolic content (TPC, by Folin-Ciocalteu assay), anthocyanins (ACY, by pH differential method) and flavanols content (TFC, by vanillin assay) of the samples along with their antioxidant activity (DPPH radical scavenge method, RSA) and antibacterial activity (minimum inhibition concentration, MIC) were determined during 16 weeks of storage under vacuum condition at 15±2 °C. Meanwhile, dietary fiber profile was evaluated by using gravimetric-enzyme method. Results showed that dietary fiber contents of PN-P, PN-S, M-P and M-S were 57-63% d.m. with the majority of insoluble fraction. Freeze dried WGP retained the highest bioactive compounds with TPC 21.19-67.74 mg GAE/g d.m., ACY of 0.35-0.76 mg Mal-3-glu/g d.m., TFC of 30.16-106.61 mg CE/g d.m. and RSA of 22.01-37.46 mg AAE/g d.m., followed with ambient air dried samples. Overall, TPC, TFC and RSA were higher in PN than in M, and higher in pomace than in skins, while reverse results were observed in ACY. All samples lost significant amount of bioactive compounds during storage, in which ambient air and freeze dried samples had TPC reduction of 32-56% and 35-58%, respectively at the end of 16 weeks of storage. RSA in PN-P and M-P remained more than 50 mg TE/g d.m., meaning WGP still met the criteria of ADF definition after 16 weeks of storage. WGP extracts showed higher antibacterial efficiency against L. innocua than that of E. coli with MIC of 2, 7, 3 and 8% against L. innocua, and 3, 6, 4 and 9% against E. coli for PN-P, PN-S, M-P and M-S samples, respectively. This study demonstrated that Pinot Noir and Merlot pomace are good sources of ADF even after 16 weeks of storage at 15 °C and vacuum condition.
Due to the highest antioxidant activity (RSA 37.46 mg AAE/g) and dietary fiber content (61%), PN-P was selected as ADF to be fortified in yogurt and salad dressing. Three types of WGP: whole powder (WP), liquid extract (LE) and freeze dried extract (FDE) with different concentrations were incorporated into yogurt (Y), Italian (I) and Thousand Island (T) salad dressings. TPC, RSA and dietary fiber content, major quality attributes including pH and peroxide value (PV) during the shelf life and consumer acceptance of fortified products were evaluated. The highest ADF were obtained in 3% WP-Y, 1% WP-I and 2% WP-T samples with the dietary fiber contents of 1.98%, 2.12% and 1.83% and RSA of 935.78, 585.60 and 706.67 mg AAE/kg, respectively. WP fortified products had more dietary fiber content than that of LE and FDE fortified ones because of the insoluble fractions. The pH dropped from 4.52 to 4.32 for 3% WP-Y during three weeks of storage at 4 °C, but remained stable in WGP-I and WGP-T samples after four weeks of storage at 4 °C. Adding WGP resulted in 35-65% reduction of PV in all samples compared to the control. In WGP-Y, the viscosity increased, but syneresis and lactic acid percentage were stable during storage. The 1%WP-Y, 0.5%WP-I and 1%WP-T samples were mostly liked by consumers. Study demonstrated that WGP can be used as a functional food ingredient for enhancing nutraceutical content and extending shelf-life of the food products.
This study provided important information about the economically feasible drying methods for retaining the bioactive compounds in WGP during processing and storage and also suggested that WGP can be utilized as antioxidant dietary fiber to be fortified in consumer products to promote nutritional benefit and extend product shelf-life. / Graduation date: 2013
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