Advertisements
Advertisements
Question
In which food would you find lactic acid bacteria? Mention some of their useful applications.
Advertisements
Solution 1
Lactobacillus and other microorganisms, known as lactic acid bacteria (LAB), develop in milk. They convert lactose sugar from milk into lactic acid. Lactic acid causes casein, a milk protein, to coagulate. Milk is processed into curds, yogurts, and cheese.
- Curd: Indian curd is made by inoculating cream and skimmed milk with Lactobacillus acidophilus at temperatures of around 40°C or below.
- Yogurt: It is made by fermenting milk with Streptococcus thermophilus and Lactobacillus bulgaricus. It tastes of lactic acid and acetaldehyde. It is frequently sweetened and flavored with fruits.
- Cheese: It comprises milk curd separated from the liquid portion. Lactic acid bacteria help to curdle milk for making raw cheese.
The LAB also plays an important function in preventing microbes that cause illness in our stomach.
Solution 2
Lactic acid bacteria (LAB) grow in milk and change it into curd. As they multiply, they release acids that cause the milk proteins to thicken and also break them down partly. They enhance the nutritional value of curd by increasing its vitamin B12 content. In our digestive system, LAB are also helpful because they prevent harmful microbes from growing.
APPEARS IN
RELATED QUESTIONS
Bacteria cannot be seen with the naked eyes, but these can be seen with the help of a microscope. If you have to carry a sample from your home to your biology laboratory to demonstrate the presence of microbes with the help of a microscope, which sample would you carry and why?
Name some traditional Indian foods made of wheat, rice and Bengal gram (or their products) which involve use of microbes.
Find out the role of microbes in the following:
Single cell protein (SCP)
Which of the following is white button mushroom?
(A) Agaricus bisporus
(B) Pleurotus Florida
(C) Volvariella volvacea
(D) Candida species
Give the biological name of the following:
A symbiotic nitrogen-fixing bacterium found in root nodules.
Name the microbes that help the production of the following product commercially:
Citric acid
Which of the following microorganism is used for production of citric acid in industries?
Which of the following pair is correctly matched for the product produced by them?
Write short notes on the following:
Brewer's yeast
List the advantages of biogas plants in rural areas.
Which of the following pair is correctly matched for the product produced by them?
Concentrations of which vitamin increases, while the milk is converted into curd by the process of fermentation:
Lactic acid is formed by the process of:
A small amount of curd added to the milk to initiate the curdling is called
Match the columns.
| Product | Microbe | ||
| A | Curd | 1 | Yeast |
| B | Bread | 2 | Propionibacterium |
| C | Swiss Cheese | 3 | LAB |
| D | Statins | 4 | Monascus purpureus |
Which of the following used in Swiss cheese?
The vitamin whose content increases following the conversion of milk into curd by lactic acid bacteria is ______.
Big holes in Swiss cheese are made by ______.
Why does ‘Swiss cheese’ have big holes?
Which species of Penicillium produces Roquefort cheese?
Name a microbe used for the production of Swiss cheese.
Which type of food would have lactic acid bacteria? Discuss their useful application.
Home-made fruit juices are turbid, while the bottled ,fruit juices purchased from the market are clear. Give a reason for this difference.
Read the passage given below carefully and answer the questions that follow:
|
The bacterium Bacillus thuringiensis serovar israelensis (Bti) is commercially prepared in various formulations such as liquid, water dispersible granules, powders, and pellets. It is used as a larvicide all over the world due to its ability to produce a toxic protein that primarily targets the larvae of mosquitoes. In Sweden, Bti has been applied on a large scale in the form of commercially available granular formulation Vecto Bac G (Valent BioScience, USA). The applications have taken place in the lower Dalalven River Area to control mass outbreaks of the floodplain mosquito Aedes sticticus. |
- Why does the toxic protein kill the insects but not the bacterium?
- Can the formulation Vecto Bac G be used to eliminate the species of mosquito referred to above? Why?
