Question

Rennet is used in
A. Breadmaking
B. Fermentation
C. Cheesemaking
D. Synthesis of antibiotics

Answer 1

Hint: A complex enzyme of animal origin that helps in the coagulation of an important milk protein known as casein. This enzyme is known as rennet and is produced from chymosin or rennin.

Complete answer: A complex set of enzymes found in the ruminant of the cattle is known as rennet. Chymosin is the key component of the rennet that is used in the curdling of the casein of milk. It helps in the process of milk coagulation to form a thick curd. It starts working at a temperature of 85-105 degree Fahrenheit and even at higher temperatures. It is only deactivated when it reaches 140 F. Milk settling starts at a particular temperature range. Rennet can be liquid or solid (paste). They are easy to work with because they can be measured easily. Whereas, powdered and tablet rennet can be stored for longer periods and can remain better in warmer climates. Longer aged cheese can be produced using calf rennet because it helps in the partial breakdown of proteins. Vegetable rennet is produced from a mould (Mucor miehei). Though it is derived from the mould, there is no mould in the final product. It is equivalent to chymosin but it is not animal-derived. It has some complex proteins which impart a bitter taste after six months of ageing. Traditional and genetically engineered rennet is commonly used for the production of cheese.
Hence, the correct answer is option C.

Note: The process of cheesemaking begins with the addition of starter cultures that converts milk sugar or lactose to lactic acid. This process changes the acidity of milk which initiates milk coagulation. Finally, rennet is added to thicken milk and whey is removed.