Orientador: Fernanda Paula Collares / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-08T12:10:02Z (GMT). No. of bitstreams: 1 Marangoni_AndreLuis_M.pdf: 949788 bytes, checksum: 48a3e3adcced1d1be2f35acb905676cd (MD5) Previous issue date: 2007 / Resumo: O presente trabalho visou avaliar a aplicação de farinha de Yacon (Polymnia sonchifolia) em produtos à base de cereais como bolo inglês, biscoito tipo "Champurrada" e snacks à base de arroz obtidos por extrusão termoplástica. Para tanto, a incorporação de farinha de Yacon nos snacks e a substituição parcial da farinha de trigo pela farinha de Yacon no bolo e no biscoito foram analisadas quantificando-se a magnitude das mudanças físicas e sensoriais nestes produtos. Para os três estudos, utilizou-se a metodologia de superfície de resposta com um delineamento estatístico do tipo composto central rotacional (com 2 variáveis independentes no caso do bolo e biscoito, e 3 variáveis independentes para o estudo dos snacks). As variáveis independentes no estudo do bolo foram as concentrações de farinha de Yacon e de farinha de linhaça. Já, para o biscoito, as variáveis foram as concentrações de farinha de Yacon e de aveia em flocos. Em se tratando dos snacks, as variáveis foram: umidade da farinha de alimentação; temperatura na 4ª e 5ª zona do extrusor; e teor de farinha de Yacon incorporada. Os bolos e os biscoitos foram analisados quanto à textura e cor instrumental (Hunterlab), densidade da massa, volume específico, além das avaliações sensoriais. Por sua vez, as variáveis dependentes no estudo dos snacks foram: propriedades físico-químicas (textura e cor instrumental, índice de absorção de água e de solubilidade em água, e índice de expansão) e sensoriais. Para o bolo, as superfícies geradas sugeriram que concentrações de farinha de Yacon variando entre 0,0% e 3,45% e teores de farinha de linhaça entre 3,18% e 6,0% resultaram em um produto de menor dureza. Para os parâmetros de cor, com concentrações mínimas de farinha de Yacon e linhaça (0,0% e 3,18%, respectivamente), obteve-se um bolo mais claro, de coloração mais amarelada e a densidade da massa atingiu valores mínimos quando o teor de linhaça foi de 6,0%, sendo que o teor de farinha de Yacon não apresentou influência sobre este parâmetro. No estudo do biscoito, a superfície de resposta indicou que quando a concentração de Yacon foi de 3,45% ou superior, e a de aveia de 6,82%, o parâmetro L* atingiu seu valor máximo. O maior valor de intenção de compra ocorreu para uma concentração de Yacon de 3,45% e de aveia de 1,18% e 6,82%. Dessas observações pode-se inferir que a concentração recomendada de incorporação de farinha de Yacon seria 3,45% e de aveia de 6,82%, considerando a faixa de valores estudada. Os snacks que apresentaram maior expansão foram obtidos a 120ºC, com teor de umidade da matéria-prima igual a 17% e concentração da farinha de Yacon de 12%. As superfícies geradas para os atributos sensoriais textura e intenção de compra, mostraram que o valor máximo para estes dois atributos ocorreram para as mesmas condições de temperatura, umidade da farinha de alimentação e teor de farinha de Yacon que propiciaram o maior índice de expansão. A utilização da farinha de Yacon (Polymnia sonchifolia) como um ingrediente funcional em produtos panificados (bolo e biscoito) e extrudados (snacks de arroz) mostrou-se viável. Os fruto-oligossacarídeos (FOS), objeto central no desenvolvimento de um produto funcional, foram conservados no processamento do Yacon até a obtenção da farinha e permaneceram em concentrações satisfatórias, de modo a suprir a ingestão nutricional de acordo com padrões difundidos na literatura / Abstract: This study aimed at evaluating the application of yacon (Polymnia sonchifolia) flour in cereal-based products such as pound cake, "Champurrada" type biscuits and rice-based snacks produced by a thermoplastic extrusion process. Thus the effect of incorporating yacon flour into the snacks and the partial substitution of wheat flour by yacon flour in the cake and biscuit were analysed, quantifying the magnitude of the physical and sensory changes in these products. Response surface methodology was used in the three studies, with a rotatable central-composite experimental design (with 2 independent variables for the cake and biscuit, and 3 independent variables for the snacks). The independent variables for the cake study were the yacon flour and flaxseed flour concentrations, and for the biscuit, the yacon flour and oat flake concentrations. For the snacks, the variables were: moisture content of the feed flour; temperature in the 4th and 5th extruder zones; and amount of yacon flour incorporated. The cakes and biscuits were analysed for instrumental texture and colour (Hunterlab), dough density and specific volume, as well as the sensory analyses. On the other hand the dependent variables for the snacks were: the physical (instrumental texture and colour, water solubility index, water absorption index and expansion ratio) and sensory properties. For the cake, the surfaces generated suggested that concentrations of yacon flour between 0.0% and 3.45% and of flaxseed flour between 3.18% and 6.0% resulted in a cake with reduced hardness. For the colour parameters, the minimum yacon and flaxseed flour concentrations (0.0% and 3.18%, respectively), produced lighter coloured cakes with a yellowish colour. The dough density reached minimum values when the concentration of flaxseed was 6.0%, whilst the yacon flour concentration showed no influence on this parameter. In the biscuit study, the response surface indicated that when the yacon flour concentration was 3.45% or above and that of the oat flakes 6.82%, the L* parameter reached its maximum value. The highest value for purchasing intention was obtained with a Yacon flour concentration of 3.45% and an oats concentration between 1.18% and 6.82%. These observations inferred that the recommended concentrations for the yacon flour and oat flakes would be 3.45% and 6.82%, respectively, considering the range of values studied. The most expanded snacks were obtained under the following conditions: 17% moisture content in the feed flour, a temperature of 120ºC and the incorporation of 12% yacon flour. The surfaces generated for the sensory attributes of texture and purchasing intention, showed that the maximum values for these two attributes were obtained under the same conditions of temperature, feed flour moisture content and yacon flour incorporation that propitiated the greatest expansion values. The use of yacon flour (Polymnia sonchifolia) as a functional ingredient in bakery products (cake and biscuit) and extruded products (rice snacks) was shown to be viable. The fructooligosaccharides (FOS), central object of the development of a functional product, were conserved during the processing of the yacon to obtain the flour, remaining in satisfactory concentrations, sufficient to supply the recommended values for ingestion according to standards divulged in the literature / Mestrado / Mestre em Tecnologia de Alimentos

O arroz integral pigmentado (vermelho ou preto) (Oryza sativa, L.) é saudável. Ambos são nutritivos, possuem elevado teor de compostos bioativos, e apresentam características sensoriais diferenciadas ao arroz integral branco. O grande destaque sob o ponto de vista de composição química é o seu elevado teor de compostos fenólicos, associado à alta capacidade antioxidante. A demanda por arroz pigmentado ainda é reduzida, porém, existe uma tendência e o interesse em agregar valor a esses grãos, produzindo alimentos alternativos como flocos de arroz, cereais matinais e snacks. O objetivo deste estudo foi desenvolver produtos extrusados expandidos a partir de duas novas cultivares comerciais de arroz integral preto (SCS 120 ÔNIX) e vermelho (SCS 119 RUBI), provenientes da Epagri/SC. Na otimização do processo considerou-se as melhores propriedades tecnológicas e a retenção de compostos bioativos. Foi investigado o efeito do processo de extrusão nos fitoquímicos e sua atividade antioxidante, antes e após a extrusão. Além disso, a aceitabilidade de dois produtos finais foi realizada com 150 consumidores. O arroz preto apresentou teores significativamente maiores de macronutrientes (proteínas, fibras e minerais) do que o arroz vermelho. O teor de compostos fenólicos totais (CFT) e flavonoides no arroz preto foi de 25% (569,3 mg eq. ác. ferúlico/100g) e 44% (496,9 mg eq. catequina/100 g), respectivamente, superior ao do arroz vermelho. Os flavonoides são representados principalmente por antocianinas no arroz preto e por proantocianidinas no arroz vermelho. O arroz preto apresentou maior atividade antioxidante. A partir do delineamento composto central rotacional as condições ótimas de extrusão foram de 15,5 e 16% de umidade e de 159 e 150ºC de temperatura, para o arroz preto e vermelho, respectivamente. O processo de extrusão resultou em perdas drásticas de TPC, flavonoides, proantocianidinas e o conteúdo remanescente não foi maior que 14% no arroz vermelho e a atividade antioxidante residual também foi baixa. O arroz preto também foi afetado significativamente pela extrusão mas em menores proporções. A concentração após a extrusão foi de 32 % (TPC), 22% (flavonoides), 11% (antocianinas) e a atividade antioxidante remanescente de 40% e 30% pelos métodos de ORAC e DPPH, respectivamente. Quanto à análise sensorial, os extrusados obtidos de arroz preto e vermelho não tiveram diferença significativa na aceitação (p≤0,05). As notas médias atribuídas por 150 provadores para todos os atributos avaliados ficaram situadas no intervalo de 4,8 a 7,7 (correspondente as categorias \"nem gostei/nem desgostei\" a \"gostei muito\") da escala hedônica de 9 pontos. Altos valores de aceitabilidade (maiores que 70%) foram observados para formato, tamanho, cor e crocância no cereal seco e consistência no cereal com leite. A menor aceitabilidade (60%) foi notada no sabor. Isto pode ser explicado pela ausência de aromatizante e/ou edulcorante na formulação. Ainda, foi observado que 26% dos provadores certamente comprariam ambos os extrusados. A farinha de arroz pigmentado é uma alternativa para a elaboração de cereais matinais extrusados na qual apresentam coloração própria, boas características nutricionais e sensoriais, além de ser um produto isento de glúten. / Whole pigmented rice (black and red) (Oryza sativa, L.) is a healthy food. Both types present are nutritious and present high contents of bioactive components, and show distinguishing sensorial properties, unlike those found in whole white rice. However, the most noticeable difference regarding the chemical composition of black and red rice is their high content of phenolic compounds, associated to a high antioxidant activity. Consumption of pigmented rice is still low, but there is an increasing trend and interest in adding value to pigmented grains, producing alternative food products such as rice flakes, breakfast cereals and snacks. Then, the objective of this study was to produce extruded rice from whole grain of black (SCS 120 ÔNIX) and red rice (SCS 119 RUBI). Rice cultivars were grown at experimental fields of Epagri/SC. The conditions of the extrusion process were optimized to achieve the best technological properties and to attain the retention of bioactivties. The phytochemical composition antioxidant activity and technological properties of the pigmented rice flour were investigated before and after extrusion. In addition, the acceptability of the two selected final products was assessed by 150 consumers. The black rice showed significantly higher contents of macronutrients (protein, fiber and minerals) than red rice. The total phenolic compounds (TPC) and total flavonoids in black rice were also 25% (569.3 mg eq. ac. ferulic/100 g) and 44%, (496.9 mg eq. catechin/100 g) respectively, higher than in red rice. In black rice flavonoids were represented mainly by anthocyanins, while in red rice the main flavonoids were proanthocyanidins. Black rice showed the highest antioxidant activity. The predicted optimum extrusion conditions were settled down at 15.5 and 16 % of moisture and 159 and 150ºC of temperature for black and red rice, respectively. The extrusion process induced a drastic loss of TPC, flavonoids and proanthocyanidins and remaining contents were not higher than 14% in red rice and residual antioxidant activity was also very low. Black rice was also significantly affected by the extrusionm but in a lesser degree. The concentration after extrusion was 32% (TPC), 22 % (flavonoids), 11% (anthocyanins) and a remaining 40 % and 30 % antioxidant activity by ORAC and DPPH methods, respectively. Consumer acceptability of extrudates was similar and the average scores awarded were located between 4.8 to 7.7 (corresponding to the categories \"not liked/disliked to \"liked so much\") for all attributes evaluated in the 9-point hedonic scale. High acceptability scores (higher than 70 %) were observed for shape, size, color and texture hardness in dry extrudates and consistency in extrudates with milk. The lowest acceptability (60 %) was noted for flavor. It could be explained because of the extrudates were not flavoured. Furthermore, it was shown that 26 % of consumers certainly would buy both extrudates. The pigmented rice flour demonstrated to be a good alternative to produce extruded breakfast cereals which had his own color, showed good nutritional and sensory properties, besides being a gluten-free product.

Different fiber types were incorporated in an extruded expanded high-protein snack food. Three dietary fibers (powdered cellulose, wheat fiber, and oat fiber) were selected based on ease of extrusion, percent total dietary fiber, visible expansion, and commercial availability. A high-fiber, high-protein snack food containing whey protein, normal cornstarch, and pregelatinized waxy cornstarch was extruded using the three selected fibers. The fibers replaced the normal cornstarch at 30, 60, and 80% yielding extrudates with three fiber levels (18, 36, and 48%). Each treatment or combination of fiber type and extrudate fiber level was extruded in triplicate. A control with no fiber added was also extruded in triplicate. Extrudate characteristics were evaluated on physical (expansion ratio, air cell size, density, and breaking force) and chemical (moisture content, water absorption index, water solubility index, water and total soluble protein , and water soluble carbohydrate) parameters. The physical and chemical characteristics of the extrudates were found to be greatly affected by combined interaction of the fiber type and level of fiber in the extrudate. As the amount of fiber in the extrudate increased, moisture content increased (p < 0.0001) associated with a decrease in expansion ratio (p < 0.0001), air cell size (p < 0.0001), and water solubility index (p = 0.0013) and increased extrudate density (p < 0.0001), breaking force (p < 0.0001), and water absorption index (p < 0.0001). Dependent extrusion parameters (pressure, motor torque, barrel and die temperature of the mix, barrel and die temperatures, residence time, and product flow rate) were recorded and analyzed. All dependent extrusion parameters were influenced by the level of fiber incorporation in the extrudates (p < 0.0001). The temperature at the die was also significantly influenced by the type of fiber used, and the level of fiber and fiber type interaction (p< 0.0001). Differences were deemed statistically significant at p < 0.05. The possibility exists to incorporate dietary fiber at levels > 30% in extruded whey and cornstarch products.

Skim milk was ultrafiltered to three lactose/protein ratios and spray dried. The skim milk powder was extruded with pearled corn starch at different moisture contents, protein contents, lactose/protein ratios, and feed rates (control variables). Response surface methodology and a central composite in cube experimental design were used. This design required 30 experimental runs with 16 factorial points, 8 axial points, and 6 center points for replication. The physical and functional properties evaluated were expansion ratio, product temperature, bulk density, color, shear stress, viscosity, and water absorption index (response variables). Scanning electron microscopy was done to evaluate the microstructural attributes of the extrudates. A quadratic model was used to express the response variables in terms of the control variables. Response surfaces were generated by assigning center point values to 2 of the 4 control variables and then solving the fitted equations as a quadratic in the remaining 2 control variables. An increase in moisture content decreased expansion ratio, product temperature, color, and water absorption index, and increased bulk density, shear stress, and viscosity. An increase in protein content decreased product temperature, shear stress, viscosity, and water absorption index, increased color, and had no effect on expansion ratio and bulk density. An increase in lactose/protein ratio decreased product temperature, viscosity, and water absorption index, and had no effect on expansion ratio, bulk density, color, and shear stress. Feed rate did not have significant individual effect on any response variable. Expansion ratio had a negative correlation with bulk density (r = -0.61) and shear stress (r = -0.62) and a positive correlation with product temperature (r = 0.52). Bulk density and shear stress were positively correlated (r = 0.69), and product temperature and water absorption index were positively correlated too (r = 0.81). Expansion ratio, bulk density, color, and shear stress were chosen to determine a combined set of extrusion conditions most likely to produce an extrudate with properties suitable for a snack-type product.

Mechanically deboned rainbow trout (Oncorhynchus mykiss) was analyzed and then used in texture studies. The meat contained a moderately low amount of fat (10% ± 2%, x ± SD). Pre-deboned meat had more calcium than deboned meat (PIF/=0.37). A combined response model predicted formulations for fish sausage that would closely duplicate the texture of commercially available processed meats. A thermal model was developed that helped verify the thermal properties of rainbow trout. Thermal conductivity was measured (k == 0.48 W/m·K) and specific heat was calculated (Cp= 3200 J/kg·K).

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.

La graine de lin extrudée (GLE), riche en acide α-linolénique, est un aliment utilisé en élevage bovin laitier pour modifier la composition en acides gras du lait vers un profil nutritionnel favorable à la santé humaine. Cependant, l’effet de la graine de lin sur les animaux est peu documenté. L’objectif était d’évaluer les effets de l’utilisation de la GLE sur les performances animales en élevage bovin laitier, puis d’en estimer les conséquences économiques au niveau de l’exploitation bovine laitière. Une méta-analyse (21 essais expérimentaux) a permis de caractériser la variabilité des performances laitières en conditions expérimentales selon la quantité de GLE et la ration associée. Une étude épidémiologique exposé/non exposé menée dans 1204 élevages sur 194056 vaches a montré une association entre la quantité de GLE et la production laitière (+ 0.4 à +1,3 kg/j) et les taux de matières utiles (-0,03 à -0,20 g/kg de TP et -0,1 à -0,9 g/kg de TB). D’autres associations ont été mises en évidence : amélioration de la fécondité et de la guérison des infections intra-mammaires. Enfin, par simulation, nous avons montré qu’un éleveur produisant un lait de meilleure qualité nutritionnelle via l’utilisation de la GLE dans les conditions d’utilisation de terrain était récompensé par un gain de marge de son atelier laitier via des effets zootechniques positifs malgré le surcoût alimentaire engendré. / Extruded linseed (EL), rich in α-linolenic acid, is a feed used in dairy cattle nutrition in order to modify milk fatty acid profile in a way to potentially improve human health. However, effects of EL on dairy cow performance are little documented. The objective was to assess the effects of EL supplementation on animal performance, then to estimate the economic consequences at a farm level. A meta-analysis (21 experimental trials) allowed us to characterize the variability of animal responses related to the quantity of EL and the basal diet composition. A cohort study performed on 1204 herds and 194056 cows displayed an association between quantity of EL and milk yield (+ 0.4 à +1,3 kg/d), and milk contents (-0,03 to -0,20 g/kg MPC and -0,1 to -0,9 g/kg MFC). Other beneficial associations were highlighted: a decrease in number of days open and a better probability to cure of intramammary infections. Finally, we demonstrated that a farmer willing to modify the fatty acid composition of the milk to improve human health face higher feed costs but can be rewarded by better animal performance that increase profitability of the farm.

Submitted by (edna.saturno@ufrpe.br) on 2017-02-16T15:07:14Z No. of bitstreams: 1 Mauricio Nogueira da Cruz Pessoa.pdf: 716355 bytes, checksum: 41120b87fa94d8d978b32032793ede5f (MD5) / Made available in DSpace on 2017-02-16T15:07:14Z (GMT). No. of bitstreams: 1 Mauricio Nogueira da Cruz Pessoa.pdf: 716355 bytes, checksum: 41120b87fa94d8d978b32032793ede5f (MD5) Previous issue date: 2008-10-01 / The statistical evaluation of the use of extruded and pelleted ration in the Litopenaeus vannamei shrimp culture, under field conditions, were done with the objective of determinie the advantages of these diets on shrimp performance index. To perform the analyses were used 481 crops, from 8 commercial farms of northeastern Brazil. It was the technique used multiple linear regression to determine the parameters of handling variables that influenced the responses of crops such as production, productivity, the conversion factor of food (FCA), the weekly average growth, the average weight end, the quantity of feed consumed and survival. These responses were measured by the density of storage, but also in time of cultivation. It may be noted that there was no significant difference (P ≥ 0,05) between the use of feed on the variables average weight final and average weekly growth, as in other variables can be observed that for the storage density of 15 shrimps.m-2 there were differences of up to 20.1% in the FCA in favour of extruded ration, a production 9.7% higher when using pelleted ration of feed consumption and a 33.2% higher in pelleted feed. For densities of 60 shrimps.m-2 the difference in the FCA was 18.8% lower when you used to feed pelleted, production was 7.2% higher if using pelleted diet, consumption of feed was 8.5% lower when used if pelleted diet and productivity was 10.3% higher when the extruded feed was used for that density. / Avaliações estatísticas do uso de ração extrusada e peletizada, em cultivos do camarão Litopenaeus vannamei, nas condições de campo, foram realizadas com o objetivo de determinar as vantagens sobre os índices zootécnicos dos camarões. Análises foram feitas utilizando-se 481 cultivos, provenientes de oito fazendas comerciais do nordeste do Brasil. Foi utilizada a técnica de regressão linear múltipla para estimar os parâmetros de manejo que influenciaram nas variáveis respostas dos cultivos tais como produção, produtividade, fator de conversão alimentar (FCA), crescimento semanal, peso final, quantidade de ração administrada e sobrevivência. Essas variáveis foram avaliadas em função da densidade de estocagem e do tempo de cultivo. Não houve diferença significativa (P ≥ 0,05) entre o uso das rações sobre as variáveis, peso final e crescimento semanal. Nas demais variáveis observou-se que na densidade de estocagem de 15 camarões/m2 houve diferença de até 20,1% no FCA a favor da ração extrusada, uma produção 9,7% maior quando se utilizou ração peletizada e um consumo a mais de 33,2% de ração peletizada. Para densidades de 60 camarões/m2 a diferença no FCA foi de 18,8% menor quando se utilizou ração peletizada, a produção foi 7,2% maior utilizando-se ração peletizada, o consumo de ração foi 8,5% menor com ração peletizada e a produtividade foi 10,3% maior quando a ração extrusada foi utilizada.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-06T10:45:53Z No. of bitstreams: 1 2015 - Vanessa Coelho da Silva Toledo.pdf: 4854286 bytes, checksum: 0bbdd5bc8b7aac66121fe8a0873e3abc (MD5) / Made available in DSpace on 2017-01-06T10:45:53Z (GMT). No. of bitstreams: 1 2015 - Vanessa Coelho da Silva Toledo.pdf: 4854286 bytes, checksum: 0bbdd5bc8b7aac66121fe8a0873e3abc (MD5) Previous issue date: 2015-04-15 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The extrusion technology enables energy-efficient, with minimal waste and continuously, the processing of cereals. This technology has been used to generate low nutritional and caloric value products, low in dietary fiber, high fat and sugars. The use of raw materials based on whole grain rice, maize and sorghum for the production of products ready for consumption, besides being an excellent source of fiber, it is a good alternative for patients celiac and / or gluten restriction. The objective of this work was to study the effect of the mixture of whole grains (rice, maize and sorghum), submitted to the thermoplastic extrusion process. These mixtures were processed on a single screw lab extruder in the following conditions, which were held constant: Moisture mixtures of 14%, screw rotational speed of 200 rpm, tempera-ture of the heating zones of the extruder (feeding zone until the output of the matrix): 1st Zone - 50 ? C, 2nd - and 3rd 100 - 130, the vertical feeder screw rotation of 15 rpm at (-5 kg / hr). As experimental design, various fractions of whole grain flours were used (corn, rice, sor-ghum). Treatment 1 (T1) consisted of 70% corn; 15% rice, and 15% sorghum; T2: (15%; 70%; 15%); T3: (15%; 15%; 70%); T4: (42.5%; 42.5%; 15%); T5: (42.5%; 15%; 42.5%); T6: (15%; 42.5%; 42.5%); T10: (33.3%; 33.3%; 33.3%); T7 and T10 central points. The whole grain flour for each of the cereals were analyzed for their proximate composition and particle size distribution. The response variables during the extrusion process were: feed rate of mix-tures and specific mechanical energy (EME); bulk density; Expansion indices (radial, longitu-dinal and volume); characterization by images; instrumental texture; paste viscosity; absorp-tion index (WAI) and water solubility (ISA). Variations between treatments were mainly at-tributed to their composition, in particular the dietary fiber content of each sample. It was ob-served that increasing fiber content in the mixture led to the reduction in radial expansion of extruded, as expected. Mixtures with more brown rice content (T2 and T4 treatments) were those who had higher radial expansion, which was attributed to lower this fiber content in rice flour, as expected. The best result was shown EME the treatment with higher corn meal con-tent and sorghum (T5). The instrumental texture analysis also highlighted the crispness (high-er Nsr) treatments more rice portion (T2 and T4). Treatment with higher fraction of corn (T1), achieved the highest paste viscosity. But the T2 treatment, also pointed to present low value for ISA. The treatment of central point (T8) has the greatest value. It could be obtained from mixtures of T2 and T4, more crispness product, expansion and better distribution of the inter-nal air cells; It is therefore recommended treatment for producing extruded. / A tecnologia de extrus?o permite com efici?ncia energ?tica, com m?nima de res?duos e, de forma cont?nua, o processamento de cereais. Este tecnologia tem sido usada para gerar produtos de baixo valor nutricional e cal?ricos, com baixo teor de fibra alimentar, altos teores de gorduras e a??cares. A utiliza??o de mat?rias primas ? base de gr?os integrais de arroz, milho e sorgo, para a elabora??o de produtos para pronto consumo, al?m de ser excelente fonte de fibras, se faz uma boa alternativa para doentes cel?acos e/ou com restri??o a gl?ten. O objetivo deste trabalho foi estudar o efeito da mistura dos cereais integrais (arroz, milho e sorgo), submetidos ao processo de extrus?o termopl?stica. Tais misturas foram processadas em um extrusor de laborat?rio de rosca simples nas seguintes condi??es, as quais foram mantidas constantes: umidade das misturas a 14%, velocidade de rota??o do parafuso a 200 rpm, temperatura das zonas de aquecimento do extrusor (da zona de alimenta??o at? a sa?da da matriz): 1? zona ? 50?C, 2? - 100 e 3? - 130, alimentador vertical helicoidal na rota??o de 15 rpm (~5 kg/h). Como delineamento experimental, foram utilizadas fra??es variadas das farinhas dos cereais integrais (milho, arroz, sorgo). O Tratamento 1 (T1) foi composto de 70% de milho; 15% de arroz e 15% de sorgo; T2: (15%; 70%; 15%); T3: (15%; 15%; 70%); T4: (42,5%; 42,5%; 15%); T5: (42,5%; 15%; 42,5%); T6: (15%; 42,5%; 42,5%); T10: (33,3%; 33,3%; 33,3%); sendo T7 a T10 pontos centrais. As farinhas integrais de cada um dos cereais foram analisadas quanto a sua composi??o centesimal e distribui??o granulom?trica. As vari?veis respostas durante o processamento de extrus?o foram: vaz?o de alimenta??o das misturas e energia mec?nica espec?fica (EME); densidade aparente; ?ndices de expans?o (radial, longitudinal e volum?trico); caracteriza??o por imagens; textura instrumental; viscosidade de pasta; ?ndices de absor??o (IAA) e solubilidade em ?gua (ISA). As varia??es entre os tratamentos foram principalmente atribu?das ? composi??o centesimal, em particular, o teor de fibra alimentar de cada amostra. Observou-se que o aumento do teor de fibra na mistura, levou ? redu??o da expans?o radial dos extrudados, como esperado. As misturas com maior teor de arroz integral (Tratamentos T2 e T4) foram aquelas que apresentaram maior expans?o radial, o que foi atribu?do ao menor teor de fibra presente na farinha de arroz, como esperado. O maior resultado de EME foi evidenciado no tratamento com maior teor de farinha de milho e de sorgo (T5). A an?lise de textura instrumental tamb?m destacou a croc?ncia (maior Nsr) dos tratamentos com maior por??o de arroz (T2 e T4). O tratamento com maior fra??o de milho (T1), alcan?ou a maior viscosidade de pasta. J? o tratamento T2, se destacou tamb?m por apresentar baixo valor para ISA. O tratamento do ponto central (T8) foi o de maior valor. Foi poss?vel obter a partir das misturas dos tratamentos T2 e T4, produtos de maior croc?ncia, expans?o e melhor distribui??o interna das c?lulas ar; sendo, portanto, os tratamentos recomendados para produ??o de extrudados.

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