Question

Determine the methods used to test for each of the following in milk.

Starch -	(A) _____
Detergent -	(B) _____
Urea -	(C) _____
Water -	(D) _____

• A. A - Vigorous shaking, B - Iodine test, C - Lactometer, D - Litmus test
• B. A - Iodine test, B - Vigorous shaking, C - Litmus test, D - Lactometer
• C. A - Iodine test, B - Lactometer, C - Litmus test, D - Vigorous shaking
• D. A - Litmus test, B - Vigorous shaking, C - Iodine test, D - Lactometer

Answer 1

The correct option is B

A - Iodine test, B - Vigorous shaking, C - Litmus test, D - Lactometer

The presence of starch in milk can be detected using iodine test. When two or three drops of iodine solution are added to milk containing starch taken in a test tube, the solution turns dark blue. The presence of water can be detected using a lactometer. The occurrence of lather after vigorous shaking of milk indicates the presence of detergent. A change in colour of litmus paper from red to blue indicates the presence of urea in the milk.