WHow does wine get so many different flavors?

From simple white wines to complex red wines, the source of the  primary flavors in wine is the grape itself. Every grape varietal comes with its own “default” flavor profile – the most common flavors  produced by the grape when it is fermented. This is also known as the  true varietal character of the wine. For example, you’ll notice apple and pear flavors virtually every time in Chardonnay, blackcurrant in  Cabernet Sauvignon, and red and black cherry flavors in Pinot Noir.  These characteristics are pretty typical of wines made from these grapes, regardless of where the wine is made and who makes it.
Beyond the true varietal characteristics of a grape, it is the subtle  differences in winemaking and location of the vineyard that makes one Chardonnay vary from another Chardonnay. The vineyard soil,  elevation, exposure to wind, proximity to cool ocean breezes, time exposed to morning fog – even the direction the vine rows are planted in relation to the sun, all have a hand in the final flavors of the  wine.
The full gamut, and complexity, of flavors in a wine are also impacted by decisions made in the vineyard and inside the winery. 
Deciding when to pick grapes is just one example. Harvesting early adds a more crisp acidity to the wine’s texture. Picking later will add richer fruitiness, and a higher alcohol level, both of which give a greater impression of sweetness.
A wine’s flavor is also influenced by using oak barrels either in the fermentation or aging of the wine, or both. Wood barrels make two large contributions to the wine’s flavor and texture. First, it helps  to soften a wine’s acidity by allowing malolactic fermentation to take place. This is a second phase of fermentation, after alcohol fermentation, that converts tart, apple-like acid into softer acid, like that found in milk.
Second, oak barrels also darken a wine’s color add a hint of vanilla,  as well as a sweet fragrance to its bouquet, and add volume to the wine on the palate. Many California Chardonnay wines that are barrel  fermented and barrel aged will exhibit these characteristics.
Technically, flavors come about through the natural creation and  interaction of chemical compounds during the growth stages of the  grape, the fermentation process, and the aging period. Wine, like all  living things, changes over time, in reaction to its environment, but  its original characteristics come through just about every time.

Len Napolitano lives in Central Coast wine country and is certified in wine by the Society of Wine Educators, Wine & Spirits Education Trust, and Chicago Wine School and continually gains knowledge from his frequent contact with California winemakers. More information is on his website, www.wineology.com . Send your questions about wine to: wineologist@earthlink.net or by mail to Len Napolitano in care of Wine Country This Week magazine. Wineology is a registered trademark of Len Napolitano.com