Give examples to prove that microbes release gases during metabolism.

Fungi and bactaria can breakdown organic compounds using fermentation. They release CO2 during this process. Common examples which show microbes release gases are:

• Dough of idli and dosa gives puffed up appearance because of release of CO2 during the process of fermentation by bactaria.

• Dough of bread is puffed up because of fermatation by Saccharomyces cerevisiae.

• The large holes in Swiss cheese are caused due to production of a large amount of CO2 during fermentation by a bacterium named Propionibacterium sharmanii.