A milkman adds a very small amount of baking soda to fresh milk. (a) Why does he shift the pH of the fresh milk from 6 to slightly alkaline? (b) Why does this milk take a long time to set as curd?
(a) pH is shifted to alkaline so that milk does not spoil by becoming sour by releasing lactic acid. (b) Milk is made alkaline by adding baking soda and the lactic acid formed, will get neutralised and therefore will take a little more time to set become acidic.
