What happens to that wine in the bottle as it ages through the years in your cellar? For a couple of years after a wine is first bottled the wines exhibits aroma’s of the grape variety and area they come from.
After about 4 or more years the wine develops what we call bottle bouquet. In wine speak, aromas are what you smell attributed to the grape variety and vineyard site. Bouquet are the smells that come from the winemaking and aging process.
In a red wine, after about 4 plus years in the bottle the tannin molecules will hook up producing longer fewer molecules from many smaller ones. When you taste tannin in a wine, it is the ends of the molecule that you taste. So, when these molecules become bigger and fewer, there will be less molecule ends to affect your palate. Thus the wine becomes softer, losing some of the aroma and replacing it with bottle bouquet. These bigger tannin molecules may become big enough to fall out of the wine forming a deposit in the bottle. The best example of this is the crusting of a port wine.
American’s tend to like wines more on the aroma side while European’s tend to like aged wines with more bouquet.