The Dal Colour Secret

The story

Baba squeezed lemon into dal, expecting it to turn red, but nothing happened. This was meant to be a well-known trick, but the magic was missing, leaving everyone confused. Later, Chintu accidentally dropped a soapy spoon into the dal. Immediately, a red streak appeared, catching Riya's eye and leaving her surprised. Aaji leaned in and pointed out that it was the turmeric, or haldi, reacting to the soap. That made soap seem like a secret ingredient to turn dal red, while lemon could do nothing. The moment left everyone wondering why dal, or even a shirt stained with turmeric, would only turn red with soap. Can soap really reveal the hidden colours in turmeric?

The science

Turmeric, or haldi, contains curcumin, which acts as a natural pH indicator. When added to neutral or acidic foods, like dal with lemon, curcumin stays yellow. However, when a base such as soap comes into contact, curcumin changes to a reddish-brown hue. This is due to a change in pH level, known in textbooks as a pH indicator reaction. That’s why a haldi stain on your shirt or in your dal turns red with soap but not with lemon.

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