Question

Why should curd and sour substances not be kept in brass and copper vessels?

Answer 1

when kept in copper or brass vessels,curd(and other acidic food items) reacts with copper and forms toxic compounds which may be unfit for human consumption,and may cause food poisoning.thus it is notadvisable to keep curd and other acidic or sour food items in copper or brass vessels.

Answer 2

Hola ^_^

If the items like curd and other sour substances are kept in brass or copper or alliuminium it would be poisonous as these substances react with each other and form harmful substances.