Question

Give scientific reasons for foam accumulates on a the surface of dal kept for a long time in summer

Answer 1

Accumulation of white foam while cooking dal may be due to two important reasons.

1.       When the lentils or dal is boiled, chemicals called Saponins are released from the tissues which have a soap-like effect and causing foaming of the water.

2.       Another theory is that while cooking dals, the proteins from the lentils leach out in to the boiling water. The air that is dissolved in the cold water bubbles out as the heat rises. These air bubbles latch on to the proteins and float on the surface of the water by forming foam.

 

Either theory explains that the foam contains proteins or chemicals that are heated and change their configuration, leading to the denaturation of proteins or damage of chemical nature.

 

Therefore, it is always advised to remove the foam while cooking

Answer 2

Explanation:

1. Dal is reach in protein
2. during summer bacteria attack dal and cause fermentation resulting in the production of carbon dioxide gas
3. therefore foam accumulate on the surface of the dal kept for long time in summer