Port is a sweet red wine with about 20% alcohol and rather low acidity and tannin. Ideally a good port should have a rich spicy flavor and in spite of its 20% alcohol, taste very smooth. Vintage style ports are very grapey. This grapiness comes from the practice of bottling these wines after they have spent 2 years in barrel. Vintage Ports are to be held in the bottle for a long time, ten years considered being just a start while truly great vintages can require 20 years and more to reach optimum maturity. They keep their grapey flavor and, through bottle aging, develop bottle bouquet, a special quality found only in bottle aged wines. It can take many years for vintage Ports to become smooth if they have some tannin when they are bottled.