Question

on keeping curd in a brass vessel for sometime it becomes bitter why

Answer 1

One should not always keeping curd in a brass vessel. Curd is made up of milk and is reactive in nature due to , with lactic acid present in it. ... And curd when kept in copper or brass vessel reacts with copper and itto forms toxic compounds, which can cause food poisoning.

Answer 2

Curd contains lactic acid. Brass is a metal.
We know that acid reacts with a metal to give Salt and Hydrogen i.e.,
Metal + Acid --------> Salt + Hydrogen