Application of Micro Z-arm dough mixer in wheat research - Effect of protein addition on mixing properties of wheat dough

A Micro Z-arm mixer has been developed which needs only four grams of flour per test. The new instrument is suitable for screening new wheat cultivars in the early phase of selection on the basis of dough mixing properties. The micro-scale instrument can also be viewed as a valuable research tool for investigation of the structure/function relationships in flour and the effects of different ingredients and additives on rheological parameters. The effects of protein addition on mixing properties of wheat dough were studied. Alkali-soluble isolates and Osborne protein fractions extracted from wheat, corn-, rice germs and amaranth seeds were used as protein additives. Dough development time, maximum resistance of dough and resistance breakdown was calculated from recorded mixing curves. Results showed that the micro-scale equipment is sensitive enough for detection of the effect of less than 40 mg of protein addition on mixing parameters. The effects of additions depend on the type of proteins added to the wheat flour and the parameters calculated from the mixing curves

Characterisation of glutenin subunits in spelt wheat (Triticum aestivum ssp. spelta L)

Este estudo tem como objecto uma prática profissional de design gráfico, sistemática e continuada e, nesse sentido, a escolha e a reflexão teórica sobre as opções tomadas em cada um dos projectos apresentados servirão o objectivo de demonstrar que aliada a uma prática autoral, cada um destes trabalhos foi executado para servir os objectivos de uma encomenda, ponto de partida essencial em todos eles. São analisadas as diferentes estratégias de abordagem, quer do ponto de vista da formulação e da fundamentação teóricas, quer do ponto de vista da sua materialização. O estudo procura entender em que medida as diferentes abordagens conceptuais e metodológicas respondem aos programas dos diferentes projectos no sentido de tornar claras as mensagens que eles procuram veicular. A investigação divide-se em três partes e uma conclusão. A primeira parte caracteriza o momento da história do design gráfico que corresponde ao nascimento do estúdio. Trata das ideias e das personalidades, da herança e da novidade, da partilha de conhecimentos. Na segunda, são descritas as condições locais que levaram à constituição do estúdio e o seu percurso. Caracteriza-se o espaço físico, o volume de projectos e a sua distribuição por diferentes áreas de actuação e também, os mecanismos de criação de uma cultura do estúdio. Na terceira parte, é analisada uma selecção de projectos que se distinguem pela qualidade dos programas e das equipas e pelos resultados obtidos. O estudo realizado revela que a prática do estúdio fba. assenta no princípio de que o design é encarado como uma forma de clarificação e ilustra o modo como esta posição influencia o processo de design. Adicionalmente, a síntese dos resultados do trabalho, demonstra a utilidade desta tese para a compreensão da prática do estúdio e do seu futuro.Tese de doutoramento em Arte Contemporânea, no ramo de Linguística, apresentada ao Colégio das Artes da Universidade de Coimbr

Expressed Ay HMW glutenin subunit in Australian wheat cultivars indicates a positive effect on wheat quality

Out of the six HMW-GS genes, 1Ay is usually not expressed in bread wheat cultivars. In the current study, an active 1Ay gene has been integrated into two Australian wheat cultivars, Livingston and Bonnie Rock, through conventional backcross approach. Three sister lines at BC4F4 generation for each cross were obtained and underwent a series of quality testing. Results show that the active 1Ay subunit increased the amount total protein, Glutenin/Gliadin ratio and unextractable polymeric protein. The expressed 1Ay also resulted in up to 10% increase of gluten content, 5% increase of glutenin, and hence increased the HMW- to LMW-GS ratio without affecting the relative amount of other subunits. Milling yield and Flour swelling were decreased in the Livingston lines and remained mostly unchanged for Bonnie Rock. Alveograph result showed that Ay improved dough strength in Livingston and dough extensibility in Bonnie Rock. Zeleny sedimentation value was found to be higher in all three lines of Bonnie Rock but only in one of Livingston derivatives. The dough development time and peak resistance, determined on the micro Z-arm mixer were increased in most cases. Overall, the integration of Ay subunit showed significant positive effects in bread making quality

Effect of additional water supply during grain filling on protein composition and epitope characteristics of winter oats

Pure oats in gluten-free diets (GFD) represent important nutritional benefits for people suffering from celiac disease (CD). However, oat cultivars do not contain the typical CD-related wheat gliadin analog polypeptides. Emerging evidence suggests that oat cultivars containing gluten-like epitopes in avenin sequences may pose potential health risks for celiac patients in rare cases, depending on the individual’s susceptibility. Consequently, it is necessary to screen oats in terms of protein and epitope composition, to be able to select safe varieties for gluten-free applications. The overall aim of our study is to investigate the variation of oat protein composition directly related to health-related and techno-functional properties and to examine how the protein compositional parameters change due to irrigation during the grain-filling period as compared to the natural rain-fed grown, in a large winter oat population of different geographic origin. Elements of an oat sample population representing 164 winter oat varieties from 8 countries and the protein composition of resulting samples have been characterized. Size distribution of the total protein extracts has been analyzed by SE-HPLC, while the 70% ethanol extracted proteins were analyzed by RP-HPLC. Protein extracts are separated into 3 main groups of fractions on the SE-HPLC column; polymeric, avenin, and non-avenin monomeric protein groups, representing 59.17–80.87%, 12.89–31.03%, and 3.40–9.41% of total protein content, respectively. The ratio of polymeric to monomeric proteins varied between 1.71 and 6.07. 91 RP-HPLC-separated peaks have been differentiated from the ethanol extractable proteins of the entire population. The various parameters identified a lot of variation, confirming the significance of genotypic variation. In addition, it was also established that the additional water supply during grain filling significantly affected the various quantitative parameters of protein content, but not its qualitative structure. This environmental effect, however, was strongly genotype-dependent. Winter oat genotypes with low levels of epitope content were identified and it was proven that these characteristics were independent of the environmental factor of water availability. These genotypes are appropriate for initiating a specific breeding program to yield oat cultivars suitable for CD patients

Towards breeding less allergenic spelt-wheat with low fodmap content — A review

Consumption of “gluten-containing” diet causes disease for a significant minority of people who consume foods derived from wheat, rye, barley, and possibly oat. The fact is, however, that in several types of diseases related to the consumption of “gluten-containing” cereals, the trigger compounds are not components of gluten. The current view of medical experts is that, excluding people suffering from celiac disease, the majority of individuals who are feeling better on the “wheat-free” or “gluten-free” diet could select a food containing much healthier, low level of fermentable oligosaccharides (often called as FODMAP). To satisfy the specific health related demands of certain consumer groups, the challenge is in front of cereal breeding to develop new, “healthier” germplasms, suitable to produce such products by the food industry. This report aims to give an overview of some aspects of recent developments in this booming area, (i) summarizing the up-to-date knowledge on cereals-related health disorders; (ii) reporting on the status of developing celiac-safe cereals, and finally (iii) highlighting the potential of developing “healthier” spelt-based cereal products through the progress in an ongoing spelt breeding program