The smell and taste of the vagina comes mostly from the fluids inside it. The taste is not quite sour, but somewhat astringent since the vagina is normally acidic. The normal pH balance is slightly acidic which helps protect the vagina from infections and odors.

Some describe the taste as being metallic due to the high levels of acidity. Ultimately, the taste and smell of the vagina depends on its pH levels.
The vagina is especially sensitive to different changes in your daily environment. Anything that affects this delicate balance will affect the smell, type of discharge and its consistency.