Fresh milk has a pH of 6 When it changes into curd (yoghurt), will there be an increase or decrease in $pH$ value? Why?

When milk changes into curd, the $pH$ value will change. The $pH$ value of milk is 6 since it is acidic. However, when the milk is converted into curd due to the action of bacteria, lactic acid is formed, which is more acidic. Therefore, the $pH$ value of the milk is reduced as it turns to curd.