Pouring wine from one container to another serves one of two purposes. It gets wine out of an unwieldy large bottle into two or more smaller ones, or it separates clear wine from sediment.
Older red wines are the ones that most often contain sediment. It is a mixture of tartrate crystals and color (all of the color in red wine is solid particles; with age, some coalesce and become too heavy to stay suspended). Sometimes whites will have deposits of ..read more