Question

Describe one test each for detecting the presence of the following in food:- (a)proteins (bstarch) (c)fats ​

Answer 1

starch-iodine test

fats-paper turns into oily.

Answer 2

Answer:

Explanation:

Answer: If we put a few drops of iodine, which is yellow or brown on the food, and if the food contains starch, the color of the iodine will change to blue or black.

For testing protein in the food, we have to add Biuret reagent. The reagent is a blue solution, but if it comes in contact with the protein, it will turn pink-purple.  

Sudan III test is done for testing the presence of fat. If there is a red stained oily layer on the surface after adding Sudan III solution, then we may conclude the food has fat.