Baking technology

Baking technology

The differences between the cereal proteins that account for the ability of wheat, and not barley and rye to be baked into leavened bread

Introduction

Wheat, barley and rye are all used in the baking of bread. All are source of nutrient and are popular in different regions across the world. They have various nutrients such as proteins and starch, which provides nutritional value. Wheat is one of the dominantly grown crop in temperate countries and is consumed by both human beings and livestock. Wheat is most poplar cereal used among the British people for making bread, cakes, pastry and biscuits. It grows well in temperate zones such as North America, UK, Southern Russia and southwest Australia (Wheat BP. 2013). This paper delineates on the protein in wheat that makes it conducive and preferable in baking of leavened break as opposed to barley and rye.

Leavened bread

Leavened bread is as result of fermentation that makes the bread to take its dough shape. Leavening is a process whereby gas is added to dough before or during baking to produce light and more easily chewed bread. Leavening bread employ various techniques such as chemical leavening that uses various chemicals such as baking powder, acidic ingredient such as buttermilk and baking soda among many others (Wellman, 2002). This chemical produces gases that make the dough to expand. Another technique uses yeast. The commonly used yeast is the saccharomyces cerevisiae and it ferments carbohydrates in the flour, which leads to production of carbon dioxide that helps to make the dough to expand when subjected to heat. Unleavened bread does not have the dome shape and taste.

Proteins in wheat

Wheat has a variety of proteins, which include albumin, globulin, glutenin, proteoses and gliadin. Albumin, globulin and proteoses are water-soluble proteins while gliadin and gluten are water insoluble proteins (Osborne, 1907). Therefore, when wheat flour is mixed with water, the soluble proteins dissolve and the insoluble; gliadin and glutenin does not dissolve but forms structures that result to the shape of the bread.

Gluten protein

The protein that makes wheat more desirable to bake leavened bread is gluten. This protein is high in wheat compared to barely and rye and therefore it is more preferable to use wheat. Gluten is a combination of gliadin and glutenin and it represents around 85 to 88 percent of the total protein in wheat flour. This proteins are not beneficial because of their nutritional value but because of their role in baking. Gluten levels in wheat makes it appropriate ingredient in the baking of leavened bread. Gluten is the only protein presence in wheat that is able to retain gases during the fermentation process to any market degree. Fermentation allows the wheat to have the features of dough when the bread is fermented. This protein is also responsible to give dough its ability to expand and form porous. Therefore, this presents one of the differences that makes; wheat preferable in making leavened bread. Studies have suggested that other proteins components in wheat flour such as albumin and globulin play no important role in determining the quality of bread flour (Wellman, 2002). The percentage of these proteins therefore is central as to why wheat is preferred. Barley and rye have high content of these proteins, which makes them unfavorable to make leavened bread because they do not give dough these qualities. This is another difference of why wheat is preferred.

When water is mixed with flour, these proteins link up end-to-end and through the links, they create an extensive interconnected network of coiled proteins that is referred to as glute. This dough is elastic and plastic and changes its shape depending on the pressure that is applied on it. The dough is able to move back and forth to its original shape depending on the pressure that is applied on it. Therefore, gluten helps to keep the walls of the bubbles to resist pressure that ensures that the dough does not burst. The dough expands as carbon dioxide trapped forms these bubbles (Osborne, 1907). Therefore, protein helps to trap this gas, which helps to give the bread its characteristics of spongy structure. Barely and rye lack this protein and therefore they are not able to make the dough to form a spongy structure characterized with the leavened bread.

Gluten has a range of molecular structures. One of the important structure is the glutenin that has distinctive elastic properties which helps to give wheat its various characteristics and in determining its suitability for various baked products. Glutenin has long chains of interlinked sub units, which form a loop and train structures that are equal (Wheat BP. 2013). However, when the glutenin is stretched, these loops and train loss their equilibrium. Gluten is also responsible for the viscosity or rather the thickness and the extensibility of the dough mix. Leavened bread that is mixed with yeast and allowed to ferment produces CO2 that is usually trapped by the network created by gluten (Osborne, 1907). This helps the dough to rise and makes the leavened bread to take its shape. Furthermore, gluten is coagulated with starch and this helps to stabilize the shape of the bread. It also has the capacity to bind water through the process of hydration. Gluten is also able to affect the texture of the bread. It also makes the bread have the chewiness characteristics.

For the flour to produce the required leavened bread, it has to be kneaded or mixed to be able to form pockets that are inflated by gases that are released by leavening agent (Wheat BP. 2013). Therefore, as the pockets inflate they make the dough to expand and take its shape. Glutens is also able to harden when it is heated because it is a protein. This hardening contributes to the formation of the shape and gives it is the required texture. Barely and rye lack enough of this protein and therefore cannot be used or are not preferred in making of the leavened bread.

Conclusion

Wheat, barley and rye are all used in baking. However, wheat is the most preferable option used to bake leavened bread. Strong wheat flour has high content of gluten that works well with yeasts to produce dough that can expand to produce leavened bread. Gluten is one of the proteins available in the wheat flour in abundance compared to barley. This protein is one of the five proteins available in wheat. Therefore, the major difference that has made wheat to be preferred in making of leavened bread is because of abundant level of gluten in wheat as opposed to barley and rye, which enhances the quality of bread that is baked from it. It helps to enhance the characteristics of bread by giving it texture, shape, and taste among many other benefits that barley and rye does not provide.

References

Osborne, T. (1907). Proteins of the wheat kernel, Carnegie institution of Washington, Publication, No. 84, 108.

Wellman, T. (2002). DESEM: Naturally Leavened Hearth Bread, Total Health, 24(3): p32.

Wheat BP. (2013). Baking. Retrieved from: http://www.wheatbp.net/WheatBP/Documents/DOC_Baking.php