31 research outputs found

    Effect of a combination of enzymes on the fundamental rheological behavior of bread dough enriched with resistant starch

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    The effect of three enzymes on the fundamental rheological parameters of bread dough with high content of resistant starch (RS) was studied. The RS was added as an alternative to increase the fiber ingestion while the enzymes, to overcome the gluten dilution. Optimum dough was formulated with partial substitution of wheat flour by RS (12.5 g/100 g) and enzymes transglutaminase (4 mg/100 g), glucose oxidase (2.5 mg/100 g) and xylanase (0.5 mg/100 g). Dough produced with RS and without enzymes was considered as control and dough without RS or enzymes was considered as regular for comparison. Fundamental rheological parameters were obtained from uniaxial extension, biaxial extension and oscillatory tests. Also, starch gelatinization and retrogradation were studied by differential scanning calorimetry. The partial replacement of WF by RS resulted in less extensible dough, whereas the addition of enzymes increased the strain hardening index allowing higher dough expansion. The addition of enzymes reduced the elastic modulus resulting in a behavior similar to the regular dough. RS was not gelatinized during baking, hence it can be considered as dietetic fiber. Wheat starch retrogradation after 7 days of storage was observed, indicating bread aging.Fil: Altuna, Luz. Universidade de Sao Paulo; BrasilFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Tadini, Carmen C.. Universidade de Sao Paulo; Brasi

    Torque measurement in real time during mixing and kneading of bread dough with high content of resistant maize starch and enzymes

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    In this work, a methodology to measure torque during dough mixing in large scale was developed and the baking performance of bread dough formulated with resistant starch (RS) and enzymes was evaluated. Dough was formulated with 12.5 g/100 g of RS and 4 mg/100 g of a mixture of enzymes, glucose-oxidase (Gox), tranglutaminase (TG) and xylanase (HE) in proportions according to a three-component mixture design of experiments. Dough was mixed in a large-scale dynamic rheometer measuring instant torque and speed in real time through a personal computer (PC) interface. Maximum torque during mixing and parameters of the dough development curves obtained from rheofermentometer were fit to mathematical models within 95 % of confidence. Gox and TG showed positive effects on the maximum height of dough, while HE showed a negative one. Also, it was found that Gox and TG in the presence of HE could be important for reducing dough weakening.Fil: Altuna, Luz. Universidade de Sao Paulo; BrasilFil: Romano, Roberto C. O.. Universidade de Sao Paulo; BrasilFil: Pileggi, Rafael G.. Universidade de Sao Paulo; BrasilFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; ArgentinaFil: Tadini, Carmen C.. Universidade de Sao Paulo; Brasi

    A first update on mapping the human genetic architecture of COVID-19

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    Use of alpha-amylase and amyloglucosidase combinations to minimize the bread quality problems caused by high levels of damaged starch

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    The objective of this work was to investigate the contribution of α-amylase and amyloglucosidase to dough fermentation process and bread quality, as an alternative to reduce the negative effects caused by high damaged starch in flour. The dough properties during the proofing process were modified by higher damaged starch content. Higher damaged starch in flour resulted into breads with darker crusts and firmer crumbs. The enzymes reduced the negative influence of damaged starch, producing a positive effect on the maximum carbon dioxide pressure reached during fermentation and the carbon dioxide volume retained by dough. Incorporation of alpha-amylase reduced dimension ratio and crumb firmness attributes; however, progressive additions of this additive produced lower bread volume and red intensity, and higher crumb firmness. The amyloglucosidase additions produced higher bread volume and red intensity of the crust, and lower brightness crust and gas cell diameter. Incorporation of amyloglucosidase was beneficial in the presence of a suitable quantity of damaged starch. The results confirmed that the α-amylase and amyloglucosidase additions significantly improved bread quality. Incorporation of α-amylase and amyloglucosidase led to higher bread loaves and lower crumb firmness throughout the storage period, promoting a longer life of the finished product.Fil: Barrera, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Tadini, Carmen C.. Universidade de Sao Paulo; BrasilFil: Leon, Alberto Edel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias; ArgentinaFil: Ribotta, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentin

    Natural antimicrobial ingredients incorporated in biodegradable films based on cassava starch

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    Biodegradable films based on cassava starch and with addition of natural antimicrobial ingredients were prepared using the casting technique. The tensile properties tensile strength (TS) [MPa] and percent elongation (E) at break [%] and the water vapor transmission (WVT) of the biodegradable films were evaluated and compared with the control (without antimicrobial ingredients). The evaluation of the Colony Forming Units per gram [CFU/g] of pan bread slices packed with the best biodegradable films, in terms of packaging performance, was also determined. The addition onto the matrix of only clove and cinnamon powders could reduce the films WVT when compared to the control, however TS and E were lower than the control and the effect of cinnamon was milder regarding this property. Since water activity of the pan bread slices packed with the biodegradable films increased considerably during the storage period, the antimicrobial effect could not be clearly determined. (C) 2010 Published by Elsevier Ltd.Brazilian Committee for Postgraduate Courses in Higher Education (CAPES)FAPESP (The State of Sao Paulo Research Foundation

    Análise físico-química e microbiológica do suco de laranja minimamente processado armazenado em lata de alumínio Physico-chemical and microbiological analyses of minimally processed orange juice stored in aluminium cans

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    Neste trabalho, suco de laranja natural foi pasteurizado em um trocador de calor a placas empregando três diferentes temperaturas de pasteurização: 82,5ºC; 85,0ºC e 87,0ºC e tempos de retenção variando de 11 a 59s, para se obter um produto minimamente processado. Um estudo comparativo foi realizado no suco de laranja armazenado em latas de alumínio em relação ao mesmo produto armazenado em garrafas PEAD, sob refrigeração, por um período de 21 dias. Análises de graus Brix, pH, acidez, sólidos insolúveis e totais e análises microbiológicas foram realizadas em amostras logo após o processamento e durante o período de armazenamento. As propriedades físico-químicas do suco de laranja pasteurizado apresentaram diferenças devido as diferenças detectadas na matéria-prima ao longo do período do estudo. O parâmetro de pasteurização mais apropriado para o suco de laranja natural foi 87,0ºC e com tempo de retenção variando de acordo com o pH do suco. Para pH 4,0 o tempo de retenção requerido foi maior. De acordo com os resultados, uma vida-de-prateleira de 15 dias foi determinada para o suco processado nas condições acima.<br>In this work, single-strength orange juice was pasteurized in a plate heat exchanger using three different temperatures: 82.5ºC, 85.0ºC and 87.0°C and holding times varying from 11 to 59s in order to obtain a minimally processed product. A comparison among orange juice samples stored in aluminium cans and in polyethylene bottles under refrigerated conditions for 21 days was carried out. Degree of Brix, acidity, pH, insoluble and total solids, and microbiological analyses were conducted soon after processing and during the storage period. The physico-chemical properties of the pasteurized orange juice showed differences due to variations in the raw material during the period of study. The most appropriate pasteurization temperature for orange juice was 87.0°C, with the holding time varying according to pH; pH 4.0 required longer holding times. According to the results, a shelf life of 15 days was determined for the processed orange juice, under the above conditions

    Impregnation of cinnamaldehyde into cassava starch biocomposite films using supercritical fluid technology for the development of food active packaging

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    In this work, supercritical solvent impregnation (SSI) has been tested for the incorporation of natural compounds into biocomposite materials for food packaging. Cinnamaldehyde, with proved antimicrobial activity against fungi commonly found in bread products, was successfully impregnated on biocomposite cassava starch based materials using supercritical carbon dioxide as solvent. Different process experimental conditions were tested (pressure, impregnation time and depressurization rate) at a fixed temperature (35 °C) in order to study their influence on the amount of impregnated cinnamaldehyde as well as on the morphology of the films. Results showed that all conditions permitted to impregnate antimicrobial active amounts superior to those previously obtained using conventional incorporation methods. Moreover, a significant decrease of the equilibrium water vapor sorption capacity and water vapor permeability of the films was observed after SSI processing which is a clear advantage of the process, considering the envisaged applications
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