Question

If metals are basic in nture and curd is acidic in nature then why curd is kept in metal vessels like alluminium vesel

Answer 1

Never, you cant keep acidic things in a metallic container (i mean even light acidic) becuase it might get  oxidized because of which  poison may get created

Answer 2

curd is never kept in an alluminum vessel.

It should always be kept in steel vessels or earthen pots which are used for cooking.