Bread crumb texture

Loci Gas cells trapped by the gluten network that, upon baking, generate the typical bread crumb texture. 

Bread crumb texture during ageing and shelf-life is one of the most investigated phenomena in rheological analysis of food products. Many studies are based on steady measurements, mostly in steady compression mode. Some approached the dynamic measurements, both in shear, and in compressive oscillatory mode. As... 

Measured quantities of the pre-ferment are mixed with flour. The dough is then subjected to the combination of intense mixing and the action of the oxidising agent. It is then extruded and cut into loaf sized portions, proved and baked. Bread made by the Do-Maker process has a very even crumb texture, which is characteristic of the process. 

Concerning bread, characteristics such as cell wall thickness, cell size, and uniformity of cell size affect the texture of bread crumb (Kamman, 1970) and also the appearance, taste perception, and stability of the final product (Autio and Laurikainen, 1997). Crumb elasticity can be predicted from its specific volume and is strongly affected by the amylose-rich regions joining partially gelatinized starch granules in the crumb cell walls (Scanlon and Liu, 2003). 

The textural implications of the above characteristics of the stress-strain relationships are not always clear. When one examines a bread loaf or a roll with the fingers to evaluate its freshness, it seems obvious that the perceived mechanical stimulus is associated with the first region of the curve. Yet, in mastication, the compact s resistance to tearing probably plays a more significant role than the first and second stages of the compression. At the point where the bread crumb is tom, however, the specimen may have already been wetted by saliva so that the relationship between the stress-strain characteristics of the dry sponge and its perceived textural properties is usually obscured. 

Moreover, the bread crumb s moisture loss during seven days of storage open to the air, also did not show a consistent dramatic effect on these two tensile parameters (Chen et al. 1994) as one would expect. The same can be said about the compression parameters, which too showed little correlation with the moisture loss, which was measurable, of course. These reported findings, if indeed representative of the three tested breads (white, Canadian and whole wheat), would suggest that the initial textural changes that accompany bread staling are quite subtle and hence cannot be always manifested in the described crude mechanical parameters. An alternative explanation is that the failure to find the expected trends was mainly due to the large scatter in the experimental results that masked the true trend, if it really existed. 

Developments are currently taking place in using the visible and NIR region for video imaging purposes. Experiments have been carried out to image meat surfaces and the textural appearance of bread crumbs. 

The baking process has been performed inside the NMR magnet and followed using the T2 relaxation time. The water mobility during storage of bread has been studied using the Ti and T2 relaxation curves. The texture parameters (elasticity and firmness) have correlated well with T2 curves of bread crumbs. 

FIGURE 15.11 (Continued) Sequential steps followed to perform the 100 g flour straight dough baking test, (h) Determination of bread height, (i) Determination of bread volume by rapeseed displacement, (j) Evaluation of crumb texture. 

Crumb An internal textural characteristic of baked products. Crumb texture is related to the tenderness or toughness of the bread and the distribntion and size of the loci or air spaces. 

Potassium bromate (KBrOj) Oxidizing agent used to improve the baking properties of flour. It enhances the formation of disulfide bonds and improves bread volume and crumb texture. 

Crowley, P., Schober, T J., Clarke, C.I., and Arendt, E.K. 2002. The effect of storage time on textural and crumb grain characteristics of sourdough wheat bread. Eur. Food Res. Technol. 214, 489-496. 

The texture of bread was evaluated based on an instrumental Texture Profile Analysis (TPA). Bread slices (height 30 mm) were compressed with a universal testing machine (Zwick 1445, Ulm, G) to 15 mm with two repeating cycles. The crumb firmness and the elastic recovery were evaluated as described in ref. 8. The modulus of deformability of starch and flour gels was evaluated as described in ref. 7. 

Bread improvers consist of substances which, added to the four fundamental bread constituents mentioned above, will improve the bread. These bread improvers are added to perfect the bread in one or more of the following ways color, bloom, size of loaf, shape of loaf, grain, texture, velvetiness of crumb, taste, flavor, aroma, zest of loaf, length of time required for staling, economy of gas production in dough, or water absorption capacity. 

Charles Hunter in Bakers Weekly, April 20, 1918, says that this bread has Burprising quality of texture, crumb, color, and volume. In commenting on it further he addB ... 

---