question_answer 13)

Find out a qualitative test for proteins, fats and oils and starch amino acids and test any fruit juice, saliva, sweat and urine for them. 

Answer:

A qualitative test for proteins. (i) Xanthoproteic Test  

Experimental Material	Observation	Inference
(a) Urine	Yellow precipitate	Formation of yellow precipitate
(b) Water	No precipitate	indicates the presence of protein in the food material.

  (ii) A qualitative test for fats. Emulsification Test  

Experimental Material	Observation	Inference
(a) Sweat	Oil droplets	Formation of oil droplets
(b) Water	No oil droplet	i.e., emulsification indicates the presence of fats in the given food material.

  (iii) A qualitative test for oils. Paper Test  

Experimental Material	Observation	Inference
(a) Food material (sample) (b) Water	Paper becomes Translucent	Opaque paper becomes translucent which indicates the presence of fats in the food  material.

  (iv) A qualitative test for starch.   Iodine Test  

Experimental Material	Observation	Inference
(a) Fruit juices (b) Water	Blue black colour	Formation of blue black colour indicates the presence of starch in the given food material.