What is the traditional drink of some parts of southern India made...

The dough, which is used for making foods such as dosa and idli is also fermented by bacteria. The puffed-up appearance of dough is due to the production of CO₂ gas. The dough, which is used for making bread, is fermented using baker’s yeast (Saccharomyces cerevisiae).A number of traditional drinks and foods are also made by fermentation by the microbes. ‘Toddy’, a traditional drink of some parts of southern India is made by fermenting sap from palms.