Question

A food sample is taken in a test-tube and a few drops of iodine solution were added to it. It was observed that the solution turned blue black. It shows the presence of which one of the following component in the food sample?
A) Proteins B) Carbohydrate C) Fat D) Vitamins

Answer 1

Answer

B) carbohydrate

Explanation:

when iodine solution to a food sample and it turns its color into blue black, it represents the presence of starch. And since starch is a form of carbohydrate, the answer is carbohydrate.

Answer 2

Option B) The food sample shows the presence of carbohydrates.

• When iodine comes in contact with starch or carbohydrate, it tends to show blue-black coloration.
• This technique is used as a test to determine the presence of starch in foodstuff.
• If the sample does not contain carbohydrates it tends to show orange coloration.
• Since the sample turns the orange color of iodine to blue-black it contains carbohydrates.