Some may be surprised to learn that there are only two ingredients in wine: grapes and yeast. Yet, white wines can be described as having flavors that include lemon, lime, grapefruit, apple, peach, pear and orange. And red wines can be described as having flavors of cherry, raspberry, strawberry, blackberry, blueberry, plum and fig. And then there are descriptions of vanilla, butterscotch, caramel, chocolate, tobacco, leather, and even tar, just to name a few. But, if wine is only made from grapes and yeast, how do wines get all those other flavors?
When you sip a wine, you are getting information from your tongue, nose and nasal passages. And while there are only the four tastes being detected by your tongue there are a multitude of aromas being detected by your nose and nasal passages. The aromas get released by the wine through the alcohol, which is lighter than air, and evaporates easily from your glass. Your brain then puts together the information on the tastes and smells of the wine and equates them with tastes and smells that you already know. Thus, those amazing little grapes are able to cause your brain to sense additional fruit flavors without even a trace of the fruits actually being in the wine.
Aging wine in oak barrels also adds many other dimensions to the flavors in wines. Oak barrels can add flavors of vanilla, butterscotch, coconut, toffee, caramel, butter, mocha, coffee and smokiness.
So, yes, wine is made from grape juice and yeast but can have a multitude of wonderful flavors. Cheers!