Non-Destructive Imaging of Bread and Cake Structure During Baking

Bread aeration and dough rheology: an introduction

“…With the crust set but the bubbles at the centre of the loaf still expanding, there is substantial compression of bubbles near the crust. This has been demonstrated clearly by the work of Whitworth and co-workers (Whitworth and Alava, 2005;Whitworth, 2008), whose dramatic images from X-ray tomography of baking loaves (see Fig. 12.4 ) have shown how the fi nal crumb structure arises from a relatively small proportion of the bubbles originally near the centre, the rest being compressed out of existence (or least out of sight) between this expanding centre and the rigid crust.…”

“…Both techniques exploit the large difference in the density of air bubbles and the dough matrix to permit a quantifi cation of the bubbles in the dough. Tomography has been used for examining the dough's evolution during proving and baking and the resulting solid crumb (Falcone et al , 2005;Whitworth, 2002Whitworth, , 2008Whitworth and Alava, 2005;Whitworth et al , 2005), and with the increasing availability of commercial bench-top micro-tomography instruments, there are likely to be more studies investigating the nature of dough aeration with this technique; this is one of the most exciting prospects for the future of dough aeration studies. One diffi culty is that the dynamic nature of bubbles in the dough confounds attempts to acquire high-contrast images.…”

Bread crispness and morphology can be controlled by proving conditions

“…To get a better understanding of the role of morphology on water transport kinetics, the morphology needs to be characterized. X-ray microtomography (lCT) has been used to characterize cellular morphologies (Babin et al, 2006;Lim & Barigou, 2004;van Dalen, Notenboom, van Vliet, Voortman, & Esveld, 2007;Whitworth & Alava, 2004). It proved to be a very useful technique in view of its non-invasive character.…”

Effects of crust constraints on bread expansion and CO2 release

“…Recent advances have been proposed in continuous, non-invasive monitoring of bread baking (Hong, Yan, Otterburn, & McCarthy, 1996;Wagner, Loubat, et al, submitted for publication;Whitworth & Alava, 2004) based on use of MRI (magnetic resonance imaging) and X-ray tomography. Only local porosity (volumetric gas fraction) and large-sized gas cells can be monitored since the observation scale is about one square millimetre.…”