Rheological and microstructural evolution of the most common gluten-free flours and starches during bread fermentation and baking

Mechanistic relations between the evolution of the starch/flour structure, dough rheology and bread quality were investigated using the most common flours and starches in gluten-free bread-making. Micrographs showed that the small wheat starch granules filled the spaces of the big granules, forming a uniform starch-hydrocolloid matrix. This granular advantage decreased the consistency and increased the uniformity of wheat-starch based doughs throughout fermentation, as shown by micrographs and the higher critical strain. The viscoelastic properties of the different doughs strongly influenced the bread volume and the crumb texture. Thus, starch-based breads showed higher specific volume and lower hardness, especially those made with wheat starch, whose lower pasting temperature also reinforced the continuous phase of the crumb. On the other hand, the large potato starch granules did not form a continuous starch-hydrocolloid matrix, resulting in breads with the lowest specific volume, elasticity, cohesiveness and resilience, and the highest hardness

Fruit and vegetable by-products as novel ingredients to improve the nutritional quality of baking foods

The industrial manufacturing of fruits and vegetables generates approximately 50% by-product waste, causing a negative environmental impact and significant expenses. Nevertheless, fruit and vegetable by-products (FVB) are rich nutrients and extranutritional compounds that contribute to bowel health, weight management, lower blood cholesterol levels and improved control of glycemic and insulin responses. Due to the positive influence of FVB fibers and bioactive compounds during the digestion of glycemic carbohydrates, such as starch, baked goods are ideal food systems to accommodate FVB, since most of them have a high glycemic index. Therefore, this is an area of recent interest with critical environmental, economic and health implications worldwide. However, the utilization of FVB in baked goods leads to the loss of acceptability, in many cases caused by a lack of understanding of the physical structure and composition of FVB and their effects on food quality. The objective of this review is to provide a mechanistic understanding of the impact of the physical structure and composition of FVB on common baked goods and their influence on the nutritional and physical quality of the resulting product. This review will support the use of FVB as ideal ingredients while improving the added value of waste streams.Spanish Ministry of Economy and Competitiveness (Project AGL2014-52928-C2) and the European Regional Development Fund (FEDER

Texture development in gluten-free breads: Effect of different enzymes and extruded flour

Producción CientíficaOne of the main problems with gluten-free breads is their texture and their rapid staling. In this work the influence of different enzymes (one protease, one lipase and two amylases) and of extruded rice flour on rice-bread texture and texture development was studied. For this purpose, the development of firmness, cohesiveness, resilience, springiness and chewiness was modelled and the parameters that define the initial values and the development of these characteristics were measured. The addition of lipase and extruded flour increased bread volume and reduced the initial firmness and hardening of breads. There was an early fall in cohesiveness and resilience, with minimum values reached a few days after elaboration. There were 99.9% significant correlations between bread density and firmness, springiness and chewiness development. PRACTICAL APPLICATIONS This methodology simplifies the study of gluten free breads textural parameters during storage and the result interpretation. Moreover, the correlation analysis has demonstrated that the number of textural parameters of gluten free breads to study can be reduced. Finally, the results obtained show that use of enzymes and extruded flours decreases bread staling

Effect of different extrusion treatments and particle size distribution on the physico-chemical properties of rice flour

Producción CientíficaRice flour is an interesting alternative for developing gluten free products, but its features do not meet the process requirements. The objective of this study was to modify the functional properties of rice flour by combining extrusion and size fractionation. Different extrusion conditions were applied to vary the severity of the treatment on the flour constituents. Extrusion and mechanical fractionation of the rice flours modified their behavior affecting hydration, thermal and pasting features, besides their susceptibility to enzymatic hydrolysis. Thermal properties (temperature and enthalpy) increased with the intensity of the extrusion and that effect was intensified with the greatest particle size of the flours. Fine flours with stronger extrusion showed the highest susceptibility to enzymatic hydrolysis and extrusion process increased that effect. Overall the combination of both physical treatment maybe an attractive alternative for obtaining clean label rice flours with modified features

Physicochemical modification of native and extruded wheat flours by enzymatic amylolysis

Producción CientíficaEnzymatic hydrolysis could be an alternative way to modify flour functionality. The effect of two different enzymes, α-amylase and amyloglucosidase, and their combination on microstructure, oligosaccharide content, crystalline order, pasting, gel hydration, and colour properties of native and extruded wheat flours was investigated. Micrographs showed different mechanisms of actuation of the different enzymes on native and extruded flours, achieving greater than 300% and 500% increases of glucose and maltose contents, respectively, in extruded flours compared with their native counterparts. Native flours displayed higher values of water absorption capacity and swelling power than extruded flours. Flours treated by a combination of amylase and amyloglucosidase showed low swelling power. Regarding colour, native flours were darker and more reddish than extruded flours, whereas flours treated by amyloglucosidase, and therefore had a higher glucose content, were darker and more reddish

Effect of the addition of soluble (nutriose, inulin and polydextrose) and insoluble (bamboo, potato and pea) fibres on the quality of sugar-snap cookies

Dietary fibre intake can help to improve the health of the population. Cookies are one of the most consumed bakery products. The aim of this study was to investigate the influence of different fibres on cookie quality. Soluble fibres (nutriose, inulin and polydextrose) decreased dough consistency favoured cookie spread during baking and produced wider and thinner cookies. In contrast, insoluble fibres (elongated and rounded) showed an opposite trend increasing dough consistency and giving rise to cookies with higher moisture, lower spread factor and higher hardness. Long insoluble fibres gave rise to harder cookies and with lower spread factor. Cookies made with soluble fibres were darker than the control cookie and cookies containing insoluble fibres. Therefore solubility and shape of insoluble fibres play an important role in cookie quality. Fibre selection will be key to enriched cookies development

Automatización del desarrollo de aplicaciones web mediante el enfoque mda-mde

Este documento describe el proceso de desarrollo del Trabajo de Grado titulado Automatización del desarrollo de aplicaciones web mediante el enfoque MDA-MDE, enmarcado dentro del grupo de investigación ISTAR del Departamento de Ingeniería de Sistemas de la Facultad de Ingeniería de la Pontifica Universidad javeriana. En el transcurso de este Trabajo de grado, se propone aplicar la metodología MDA (Model Driven Architecture) - MDE (Model Driven Engineering) para la creación de aplicaciones web, definiendo un lenguaje de modelado para representar aplicaciones web independientes de tecnología. Adicionalmente, con base en el modelado, se realiza un transformador de código para la tecnología específica JEE6 (Java Enterprise Edition 6).Ingeniero (a) de SistemasPregrad

Nivel de Cumplimiento del protocolo MINSA, en el abordaje del embarazo prolongado en el Hospital Bertha Calderón Roque en el periodo Septiembre–Octubre 2014

Embarazo postérmino (EP) es aquel que se extiende más allá de las 42 semanas de amenorrea completa o 294 días del último periodo menstrual. Se considera que un embarazo prolongado se asocia a mayor morbi-mortalidad perinatal. El riesgo de mortalidad fetal aumenta en 2,5 veces en gestaciones de 41 a 42 semanas, así mismo está asociado con distocia de labor y cesárea. Se estima que de 4 a 19% de los embarazos alcanzan las 42 semanas y del 2 a 7% completan 43 semanas. En otros estudios la incidencia varía entre el 5 y 8% de los partos y es considerado de alto riesgo por condicionar una mayor morbimortalidad. La mortalidad fetal aumenta después de las 42 semanas y se duplica a las 43 semanas. Aproximadamente un tercio de las muertes se deben a asfixia intrauterina por insuficiencia placentaria, contribuyendo además con la mayor incidencia de malformaciones, especialmente del sistema nervioso central. A la asfixia perinatal se agrega además, la compresión del cordón umbilical y el síndrome de aspiración meconial. El retardo del crecimiento y la macrosomía fetal son condiciones que se observan con mayor frecuencia en el embarazo prolongado. La macrosomía constituye factor de riesgo para traumatismo obstétrico (fractura de clavícula, parálisis braquial, céfalo hematoma). Otros riesgos son la dificultad para regular la temperatura y complicaciones metabólicas como hipoglucemia y policitemia. El 20 a 25% de los recién nacidos postérmino concentra el alto riesgo perinatal. En el momento actual, tomando en cuenta los elementos biofísicos y teniendo una buena clínica obstétrica de base: anamnesis, altura uterina, circunferencia abdominal, volumen del líquido amniótico, ganancia de peso materno y la prueba de movimientos fetales, permiten un seguimiento clínico adecuado de estos pacientes

Influence of the addition of extruded flours on rice bread quality

Producción CientíficaThe extrusion may improve coeliac bread quality by modifying the functional properties of flour. This study investigates the influence of the substitution of 10% of rice flour by extruded rice flours (three intensities of treatment and two particle sizes) on the characteristics of gluten-free bread (specific volume and texture) at constant consistency. The microstructure and rheology of the doughs obtained and their behaviour during fermentation have also been analysed. The extruded flours increase dough consistency, and the effect is more noticeable with increasing intensities of treatment. The use of extruded flours requires the addition of a larger volume of water to obtain a constant consistency. The addition of extruded flour decreases dough development, producing a lower specific volume and greater bread hardness. This effect is minimized by increasing the particle size. The staling of bread from 24 to 72 hours is less noticeable with a larger particle size. PRACTICAL APPLICATIONS This study evidences that the use of extruded flours in rice bread making allows increasing dough hydration and therefore the bread yield while decreasing bread staling. However, the correct selection of extrusion treatment and flour particle size is essential to achieve appropriate results, being preferable the use of coarse flours with more intense extrusion treatment

Mechanically fractionated flour isolated from green plantains (M. cavendishii var. nanica) as a tool to increase the dietary fiber and phytochemical bioactivity of layer and sponge cakes

This article describes the effect of mechanically fractionated flours from green bananas on the nutritional, physical and sensory attributes of two types of cakes (sponge and layer). A plausible 30% replacement of banana flour in the formulation of layer cakes is demonstrated, finding only a small decline in the sensory perception. On the contrary, sponge cakes were noticeable worsened with the use of banana flours (lower specific volume, worse sensory attributes and higher hardness), which was minimized when using fine flour. Both layer and sponge cakes exhibited an enhancement of the resistant starch and dietary fiber content with the replacement of green banana flour (up to a five-fold improvement in RS performance). Moreover, sponge cakes yielded more polyphenols and antioxidant capacity with banana flours, especially with the coarse fraction. Therefore, results showed that a mechanical fractionation allowed a feasible nutritional enhancement of cakes with the use of banana flours