Filiz Koksel

Ultrasound as a tool to study bubbles in dough and dough mechanical properties: A review

Investigation of dough mechanical properties using low-intensity ultrasound is now reasonably well established. In this review, an introduction to the fundamentals of ultrasound propagation in non-scattering and in scattering media is followed by several examples of how low-intensity ultrasound is used as a research tool for exploring the bubble size distribution in breadmaking dough and evaluating doughs mechanical properties. Utilization of ultrasonic techniques for quantitative assessments of bubbly dough structure and characterization of dough mechanical properties as affected by dough formulation are pointed out.

Ultrasonic Characterization of Unyeasted Bread Dough of Different Sodium Chloride Concentrations

ABSTRACT Altering the properties of dough by reducing sodium chloride (NaCl) content affects aeration processes during mixing. The effect of NaCl concentration on the bubble size distribution (BSD) in unyeasted doughs was investigated by an ultrasonic transmission technique through analysis of frequency-dependent ultrasonic phase velocity and attenuation coefficient. As NaCl concentration was decreased, the volume fraction of gas in the dough increased, resulting in a larger attenuation coefficient for the dough. From the peak in attenuation coefficient, estimates of the median radius and the width of the lognormal BSD in the dough were extracted, both of which were sensitive to the doughs NaCl concentration. As NaCl concentration was reduced, the bubble radius decreased and the width of the distribution increased, in accordance with expectations arising from changes in the doughs consistency. Over the course of 150 min, the radius increased (40–50%) and the width decreased (4–8%) for all dough formulat...

Bubbles in noodle dough: Characterization by X-ray microtomography

Bubbles, found in a huge variety of food products, are known to afford desirable quality attributes, especially those related to texture, mouthfeel and taste. However, the presence of bubbles and their effects on wheat flour noodles is an aspect that has been, until now, largely overlooked, despite the positive and negative connotations of bubbly inclusions on Asian noodle quality. X-rays from a synchrotron source (Biomedical Imaging and Therapy facility at the Canadian Light Source) were used to rapidly and non-destructively acquire tomographic images of noodle dough. Appropriate image analysis protocols were used to determine the bubble size distribution, the orientation of bubbles, and their position within the dough sheet. The effect of processing (one or multiple lamination steps) on bubble properties in the dough that was subsequently sheeted (gradual elongation and reduction in thickness) was investigated. Bubble size distributions, well captured by lognormal distribution function, showed that the lamination process induced bubble entrapment and reduction in bubble size. Bubbles were found to be flat, elongated and oriented in the sheeting direction, this effect being less for doughs laminated ten times (90° rotations between lamination steps). Interestingly, a gradient in concentration of bubbles within the dough sheet was found from the noodle core to the sheet edges. Aging effects were also apparent. This first non-destructive study of bubbles in wheat-flour noodle dough provides a more complete knowledge of the dough sheets internal structure, and how it originates via processing, and this has repercussions on the overall quality of Asian noodles.

Kinetics of Bubble Growth in Bread Dough and Crust Formation

The final texture, aerated structure, and palatability of bread strongly depends on the creation of gas bubbles during the mixing process, the control of their growth in the dough matrix during subsequent breadmaking stages, and their retention until the dough matrix is set. Therefore, gas production and gas retention in the bread dough are crucial during the breadmaking process in order to make good-quality bread. The gas production in the dough is through CO2 generation by yeast or by chemical leavening agents during fermentation and release of water vapors from the dough matrix due to high temperature during baking. The retention of these gases is impaired by physical instability processes, particularly the coarsening of bubbles, that invariably occur during breadmaking.

The Future of Grain Science: Grain Science in Canada: A National Priority

The high ratio of crops to population ensures that Canada is a significant force in export markets for both grains and oilseeds. Wheat has long been the kingpin of cropping systems in Canada, but other grain, grain legume, and oilseed crops find favor as well as producers take advantage of market opportunities and productivity enhancements. According to Statistics Canada, in 2014 Canadas top seven crops were spring wheat, canola or rapeseed, maize or corn, barley, soybeans, durum wheat, and oats. The focus of this article is wheat. Substantial changes have occurred in Canadas wheat industry over the last five years that will likely alter Canadas grain science and research landscape in the coming years. Some of these changes are highlighted. Because private industry and government both recognize the economic importance of grains to Canada, cereal science continues to be a key element of Canadas research activities. The research training opportunities afforded by cereal science for young professionals, ...