Question

During summer season,a milkman usually add a very small amount of baking soda to milk. Why?

Answer 1

because milk is slightly acidic so to neutralise it small amount of Nahco3
is added which is alkaline basic so it neutralise the milk bitter taste

Answer 2

During summer temperature is High and hence lactobacillus increases which converts into lactic acid decreasing the pH of the milk. The milk man adds baking soda to the milk to increase the pH of the milk as it is a base and neutralises the milk in summer