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Microbes in Human Welfare — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYMicrobes in Human Welfare4 Marks
Question
Microbes are useful in household products. Explain this with suitable examples
✓

Answer

We use microbes. Our products are derived from them everyday.
(1) Curd: LABs are lactic acid bacteria.
→ They grow in milk and convert it to curd.
→ During growth, the LAB produce acids that coagulate and partially digest the milk proteins.
→ A small amount of a curd added to the fresh milk as inoculum or starter contain millions of LAB, which at suitable temperatures multiply, thus converting milk to curd.
→ LAB improves milk quality by increasing vitamin B12.
→ In our stomach too, the LAB play very beneficial role in checking diseases causing microbes.
2. Cheese:
→ Cheese is an edible substance. Microbes are used at different stages of cheese. making.
→ Different varieties of cheese are known by their characteristic texture, flavour and taste which is given by specific microbes used in the cheese production.
→ The large holes in "swiss cheese" are due to production of a large amount of carbon dioxide by a bacterium named Propionibacterium sharmanii.
→ The "Roquefort cheese" are ripened by growing a specific fungi on them, which gives them a particular flavour.
3. Batter:
→ The batter of dosa and idli is fermented by using bacteria. This batter looks puffed because of the production of carbon dioxide.
→ The dough, which is used for making bread, is fermented using saccharomyses cerevisiae- baker's yeast.
4. Toddy:
→ Some traditional drink and food is also produced by the help of microbes through fermentation.
→ In South India, traditional drink toddy is made by fermenting sap from palms.
5. Other food items:
→ To produce different food items fish, soyabean, bamboo etc. are passed through fermentation.

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