How to tell if idli batter is properly fermented?

Question

Learn visual and aromatic signs that show your idli batter is ready to steam.

Answer 1

Properly fermented idli batter will have increased in volume, have a slightly sour aroma, and exhibit a light and airy texture with tiny bubbles throughout.

Detailed Explanation:

Fermentation is crucial for achieving soft and fluffy idlis. Here's how to determine if your idli batter has fermented correctly:

1. Volume Increase: The batter should have noticeably increased in volume, typically by at least double its original size. This is due to the production of carbon dioxide gas by the fermenting microorganisms.

2. Aroma: A slightly sour and tangy aroma is a good indicator of successful fermentation. It shouldn't smell foul or overly acidic.

3. Texture: The batter should appear light and airy. Gently stir the batter and observe its texture. You should see tiny bubbles dispersed throughout, indicating the presence of trapped carbon dioxide.

4. Float Test (Optional): Drop a small spoonful of the batter into a bowl of water. If it floats, it's a good sign that the batter is well-fermented. However, this test isn't always reliable, as other factors can influence buoyancy.

If the batter hasn't fermented enough, it will be dense, lack the sour aroma, and won't have increased significantly in volume. If it has over-fermented, it will have a very strong, unpleasant sour smell and may have collapsed slightly.

Pro Tip:

Fermentation time varies depending on the ambient temperature. In warmer climates, fermentation may take only 8-12 hours, while in colder climates, it can take up to 24 hours or longer. Keep the batter in a warm place to encourage fermentation. You can use your oven with the light on or an Instant Pot with the yogurt setting.