Question

when we left wheat dough in after a few days it start emit foul smell why

Answer 1

because of the microorganisms like fungus attacking it...(anaerobic respiration)

Answer 2

Your answer :

Wheat dough when kept in open for few days, following activities takes place:

1. Formation of fungus.
2. Reproduction of yeast.

These fungus and yeast when present in dough, it will become unfit for eating or for use. Since formation of fungus takes place in dough, so it gives a foul smell.

Hope this helps.

Have a nice day =)