Foam accumulates on a the surface of ‘dal’ kept for a long time in summer.

Question

Give scientific reasons:

Foam accumulates on a the surface of ‘dal’ kept for a long time in summer.

Answer 1

• Dal is rich in proteins. 
• During summer, bacteria attack the dal and cause fermentation resulting in the production of carbon dioxide gas. 
• Therefore, foam accumulates on the surface of the ‘dal’ kept for long time in summer.