Question

Give examples to prove that microbes release gases during metabolism.

Answer 1

Fermentation is one metabolic process carried out by microbes which results in release of gas. It is a process of break down of complex sugars into simpler forms in the absence of oxygen. Examples of this are:

1) puffing of bread/cake dough - yeast ferments the flour resulting in the release of CO2 which escapes causing pores in the dough making it puffy and light.

2) during swiss cheese making propionibacterium sharmanii ferments milk to form CO2 which escapes and forms pores in it.

3) ruminant animals have methanogen - bacteria that ferment organic substance to release methane. They are hence useful to generate biogas.