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Question
A milkman adds a very small amount of baking soda to fresh milk. Why does this milk take a long time to set as curd?
Solution 1
Since this milk is slightly more basic than usual milk, the acids produced to set the curd are neutralized by the base. Therefore, it takes a longer time for the curd to set.
Solution 2
The milkman made the milk alkaline by adding baking soda. The alkaline medium slows down the transformation of the milk into curd. The lactic acid produced undergoes neutralisation, so the milk takes a long time to set as curd.
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