Correct Answer - Option 2 : Yeast
Concept-
Microbes belong to diverse organisms – bacteria, fungi, protozoa, viruses.
Microbes influence man's life in several ways- they are found in clothes, jams, shoes, dead wood, food products, soil, etc.
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Yeast- it is used as a fermentation agent in the bakery (bread industry) and brewery (wine industry). So, Saccharomyces cerevisiae is also called “Baker’s yeast”.
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Agaricus- it is called “gill fungi” because gills like pores are present in its fruiting body. It is also called fairy rings because its fruiting body looks like rings.
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Mucor- it is called bread mold. It grows on bread. The tip of the mycelium is black colored. Therefore, this fungus looks black colored.
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Pythium- Causes “Damping-off’’ disease in tobacco and “vegetable crops”.
Explanation-
- Bread is made from grain usually wheat.
- The selected strain of yeast (Saccharomyces cerevisiae) grown on molasses are used as Baker’s yeast.
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Yeast is added to wheat flour. And is kneaded. The kneaded flour is kept at a warm temperature until it swells up. The phenomenon is called leavening.
- The process of leavening is done by secretion of 3 enzymes by yeast-
- Amylase causes a breakdown.
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Maltase convert maltose into glucose.
- Glucose is acted upon by zymase.
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Zymase is a complex of several enzymes of anaerobic respiration which brings about fermentation.
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Fermentation of glucose mainly forms ethyl alcohol and carbon dioxide. It leaves the dough.
- The leavened dough is baked. Both carbon dioxide and ethyl alcohol evaporate making the bread porous and soft.
