Learn why dosa batter continues to bubble slowly in the fridge. Discover how the yeast is still active, just working at a much slower pace.
1 Answer
Dosa batter bubbles during cold storage due to the continued fermentation process, albeit slowed down by the lower temperature, producing carbon dioxide gas. This gas gets trapped within the batter, creating bubbles.
Detailed Explanation:
Dosa batter is a fermented mixture of rice and lentils. Fermentation is carried out by microorganisms, primarily bacteria and yeast, which consume carbohydrates in the rice and lentils and produce byproducts, including carbon dioxide (CO2). Even in cold storage, these microorganisms remain active, although their activity is significantly reduced. The lower temperature slows down the metabolic processes, but it doesn't completely halt them. As the microorganisms continue to ferment, they release CO2. Because the batter is viscous, the CO2 gets trapped, forming bubbles. The amount of bubbling depends on factors like the initial activity of the microorganisms, the storage temperature, and the duration of storage. A slight bubbling is normal and indicates that the fermentation process is still ongoing, contributing to the characteristic sour taste and fluffy texture of the dosa. However, excessive bubbling might indicate over-fermentation, which can lead to a very sour taste and a batter that is too thin.
Pro Tip:
To control the fermentation process and prevent excessive bubbling, store the dosa batter in an airtight container in the refrigerator. This helps to minimize exposure to air and further slow down the microbial activity. Also, consider using a slightly lower proportion of fenugreek seeds (methi) in your batter, as they can accelerate fermentation.