Question

Conversion of milk to curd increases its nutritional value by increasing the amount of
A) Vitamin B12
B) Vitamin D
C) Vitamin E
D) Vitamin A

Answer 1

Hint:Milk is a nutrient rich liquid that serves as a source of food for infant mammals. It is used as a source of food because it contains proteins, lactose, amino acids, vitamins and certain inorganic elements that are helpful for growth. The pH of milk is on the alkaline side ranging from 6.4 to 6.8.

Complete answer:
There are a variety of fermented products that can be obtained from milk like cheese, curd, kefir, etc. curd is primarily obtained from milk by a process called curdling. Milk is composed of globular protein called casein. Coagulation of casein can be brought about by adding a rennet or any acidic substance such as lemon juice or vinegar. The increased acidity causes the casein proteins to clump together forming curd. Curd is also formed by the action of Lactobacillus bacteria on milk. Lactobacillus ferments lactose to produce lactic acid, this lactic acid then causes the coagulation of casein. Lactobacillus along with the production of lactic acid also produces some nutrients that increase the nutritional content of curd. It contributes to an increase in nutritional value mainly by increasing the level of vitamin B12.

Hence the correct answer is option (A) Vitamin B12

Note: Curd is consumed widely throughout the world because of its good nutritional content. It contains lactobacillus, which is a member of the gut microflora in humans and is a known probiotic thus helps in improvement of gut health. It also contains high levels of other nutrients like Vitamin B12 which is further helpful for humans.