Question

The bread becomes soft and porous when the yeast cells are mixed in the lump of dough of wheat flour, because
A. Yeast is soft and flour also becomes soft.
B. Yeast produces acetic acid and alcohol which gives softness to the bread.
C. Evolution of CO$_2$ makes the bread spongy.
D. Yeast produces benzoic acid.

Answer 1

Hint: Fermentation is a natural process as well as an industrial one. It is normally carried out by yeast. It is done artificially for the manufacture of various items such as alcohol, bread, etc. Bread is produced by the fermentation process. Bread primarily includes the use of yeast.

Complete answer: The first stage is the sifting of the dough. It is achieved by extracting foreign particles, aerating the mixture, and making it more homogeneous. The next step is to use different methods to blend the dough properly. It is cut into pieces after the dough is formed, and then rounded to the form of a ball. It is important to allow the gluten fibres time to regain their extensibility so that they can be properly moulded without breaking the surface skin. Bypassing the pieces into the intermediate proofer, this is achieved. After that to form a sheet, the dough is passed through a series of rollers. This sheeted dough is formed to a cylindrical shape by passing it through pressure. The moulded parts are put into tins where they are greased. In regulated circumstances, this panned dough is passed to the final prover. To the baking oven, the dough tins are moved. The pieces of bread are de-panned, cooled, and then sliced once baking is done. Sliced bread, usually polypropylene pouches, is then wrapped in the required packaging material. One of the steps in the development of bread is fermentation with the help of yeast or better known as baker's yeast, i.e., Saccharomyces cerevisiae. It is added along with other ingredients at the time of making dough for the bread yeast and is left to rest for some time giving yeast time for the fermentation process where it transforms the sugar present in the flour to carbon dioxide and alcohol. The release of carbon dioxide at the time of baking leaves holes in the bread when the dough is baked, giving the bread it's sponginess.
The right answer is, therefore,' Evolution of CO$_2$​ makes the bread spongy '.

Note: The idea behind this technique: wheat starch is partially converted to sugar when eaten by the yeast. Fermentation is called this method. In this process, carbon dioxide is released and that results in a brittle bread texture. The wheat is hydrated to form gluten. Like silky stretched fibres, gluten emerges. The formation of carbon-dioxide contributes to the formation of gluten. In the fermentation process, alcohol is released, which adds flavors to the bread.