A milkman adds a very small amount of baking soda to fresh milk. What happens to its pH?

Question

I know that the obvious answer would be that it increases, but it is FRESH milk. Won't it consequently produce lactic acid which would neutralize the base and hence the pH would remain almost the same? Why would there be such a question in an exam if the answer would just be that it increases? PLEASE HELP FAST!

Answer 1

Baking soda is an alkaly.It will increase pH value of milk.Milk will become more dense, so adding more water gets compensated and hydrometer may give faulty but favorable reading.In case of milk getting sour, it reduces speed of becoming curd, ie. it take more time to remain as milk.

Baking soda is not an official preservative of milk / milk products. Adding baking soda is cognizable offense.

Milk chilling and pasturisation are correct method of milk preservation.

Answer 2

Milk is basic and when a base is added its pH would obviously increase. And how can lactic acid be formed ?(as you say) The answer is just that the pH increases. Such questions are many a times asked and many students get confused !!!

Answer 3

Fresh milk is slightly acidic with a pH of 6.4 - 6.7 at 25 degrees Celcius. As milk spoils bacteria turn the lactose sugar in milk into lactic acid which drops the pH.

Adding baking soda is used to adjust the pH back up to the 6.4 -6.7 range, baking soda is safe for consumption. But this really isn't a good method to lengthen the life of the milk.

ph adjustment of milk is widely practiced in the dairy industry but not many people will admit to it.