To Detect the Presence of Carbohydrates, Fats and Proteins in the Following Food Stuffs : Grapes, Potatoes, Rice, Butter, Biscuits, Milk, Groundnut, Boiled Egg

Chemistry Lab ManualNCERT Solutions Class 12 Chemistry Sample Papers

Theory
The presence of carbohydrates, fats and protein in any food stuff is detected by performing the tests for carbohydrates, fats and proteins with the extract of the food stuff. These tests do not interfere with each other.

Apparatus
Test tubes, beakers, glass rod, pestle mortar, burner.

Procedure
First prepare the extract of the given food stuff by either dry grinding in the mortar with a pestle or by boiling with minimum quantity of water extracting with a small quantity of an organic solvent after grinding the food stuff. The extracts of some of the food stuffs can be prepared as given under:
For grapes — extract the juice
For potatotes — cut into slices and boil with water
For rice — boil with water
For butter — test directly
For biscuits — boil with water
For milk — test directly
For groundnut — grind in the mortar
For boiled egg — take the white of the egg, grind and shake with water.
With the solution or the suspension perform tests for carbohydrates, fats and proteins as discussed in Expts. 10.1,10.2 and 10.3.

Observation
to-detect-the-presence-of-carbohydrates-fats-and-proteins-in-the-following-food-stuffs-1

Result
The given food stuff contains
(i)………… (ii)………. (iii)…..

Precautions

  1. Use freshly prepared reagents for performing tests.
  2. Use minimum quantities of reagents.