Question

explain the role of microorganisms in the production of any four household items​

Answer 1

Answer: Microorganisms play a vital role in our day to day lives. Four household items produced by them are curds, bread, wine and dishes like Dosa and idli

Explanation:

• Dairy products like curd are produced by the action of the bacteria called Lactic acid bacteria.
• The lactic acid bacteria partially digest milk and produce Lactic acid. It also enriches it with Vitamin B12 and makes it easy to digest.
• Bread is produced by the action of the microbe called Yeast.
• Yeast breaks down complex starch found in flour sued to make bread into simple sugars. During this process, it produces carbon dioxide and ethyl alcohol.
• The carbon dioxide produced causes the formation of air bubbles which causes the bread dough to grow.
• A similar action is seen in the making of the dosa and idli
• Wine is also produced by the fermentation action of Yeast.
• The percentage of alcohol produced is kept into account. This is because Yeast cannot survive if the percentage of alcohol is more than 13%.

Answer 2

We use microbes or products derived from them everyday.

Curd: Micro-organisms such as Lactobacillius and others commonly called lactic acid bacteria grow in milk and convert it into curd. During growth, the LAB produce acids that coagulate and partially digest the milk proteins. The starter or inoculum contains millions of LAB, which at suitable temperatures multiply, thus converting milk to curd.

Cheese: It is one of the oldest food item in which microbes were used. Different varieties of cheese are known by their characteristic texture, flavour and taste, the specificity is determined by the microbes used. For example, large holed Swiss cheese is ripened with the help of bacterium called Propionibacterium shermanii. Roquefort cheese are ripened by fungi Penicillium roqueforti.

Bread: Bread is prepared from dough, which is fermented using Baker’s yeast (Saccharomyces cerevisiae). Puffed-up appearance of dough is due to production of CO  

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 during fermentation. CO  

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 gas along with ethyl alcohol evaporate during baking, making bread porous and soft.

Dosa and Idli: The fermented preparation of rice and black gram, prepared by using bacteria.

Toddy: A traditional drink of some parts of southern India, is made by fermenting sap from palm known as Caryota urens.

Other foods: Microbes are also used to ferment fist, soyabean and bambo-shoots to make foods.