Is milk an acid or base?

Answer:  The pH of milk is between 6.5 and 6.7 when we measure it. This indicates that it is only mildly acidic. 

However, the pH value is quite near 7.0, which is considered neutral. 

Milk is a hydrogen or proton donor since it contains lactic acid. 

If we do a litmus paper test it turns to red colour the result will be neutral to slightly acidic.

Therefore, milk is acid.