What makes a red wine red?

The answer is in the skins and a winemaking process that differs markedly from whites. Many think black (red wine) grapes have red juice, but that’s not true, with the exception of alicante bouche and a couple of others. Virtually all black grapes have clear juice as do their white cousins.

The winemaking process for red wines is based on fermenting the juice in contact with the skins to extract the color, sweet tannins and many other compounds. White wines are first pressed to extract the juice, which is immediately separated from the skins. That’s a big difference.

What if the winemaker handled black grapes in the same manner as whites? What would result? This is done all the time for Champagne and many sparkling wines. Two of the major grapes for Champagne are pinot noir and pinot munier — both black grapes. Here, the juice is pressed off and separated from the skins very early in the process (as with whites) and little, if any, color is extracted. Blanc de Noir translates to a white wine made from black grapes. And when the juice of black grapes is left for a short time in contact with the skins, a traditional rosé will be produced.

The depth of color in a red wine is influenced by the thickness of the skin (varies by varietal), the length of hang time on the vine, as well as the length of time the grapes and juice are left soaking before fermentation (cold soak) and after fermentation (extended maceration). Under traditional winemaking practices, thin skinned grapes, such as pinot noir, will show a pale hue, while thicker skinned grapes such as cabernet sauvignon will exhibit a deeper color.

The skin of black grapes contains many complex elements that not only result in the color of the wine, but also add tannin (that puckering feeling in your mouth) and many antioxidants. Anthrocyanins are a complex group of molecules responsible for color and share antioxidant properties with as many as 200 polyphenols known to exist in red wine and resulting in its many reported health benefits. As wine ages, the color will lighten as these molecules combine and precipitate out to form sediment.

Now that we know what makes a red wine red, what should we do next? How about pouring a glass of your favorite and enjoy.

Don’t forget to share your comments and questions with me and other readers at http://bit.ly/mksredwine

I very much look forward to hearing from you, and I thank those who sent in their Wine Epiphanies to me in response to the Feb. 4 Wine Exchange.

Here are a few:

Fred: Prior to our honeymoon in France, the only wine we ever had was white zinfandel. It was cheap and sweet and came with the parties. In Mersault (Burgundy), we would walk into town and buy cheese, meat, a loaf of bread, and a bottle of wine for our lunch and then enjoy it in a nearby vineyard sitting in our rented Opal, using the glove compartment door for a table. We continued this enjoyable pastime throughout France.

Hugh: In 1976, I found a 1974 Joseph Phelps Insignia (its first release) at the Cannery in the San Francisco’s Financial District. I bought a bottle, some Boudin sourdough and some sopressata and my partner and I opened the wine. I took one whiff and one taste and knew that a whole new world had opened up for me.

Bob: My father poured a wine into a nondescript bottle as part of a family picnic before a UCLA vs USC football game. I was underage but allowed a small sip of wine. I was the first to taste the wine and “knew” it was something exceptional. As the rest of the family tasted the wine they all agreed. When we returned home, we discovered my father had accidentally opened a 1959 Lafite Rothschild for the picnic.

Paul: I enjoyed your article immensely, as most of us can relate to that particular bottle that “opened the door” in our discovery of the pleasures of wine. I was in college living off a meager allowance that normally allowed me to buy jugs of Paul Masson Rhine wine for about a dollar. When I saw a bottle of Grand Cru Burgundy on the shelf for the price of my entire week’s allowance, I decided to go on a starvation diet in order to find out what this fine wine thing was all about. It changed my life!

Zinful 1 Napa: Coors was my beverage of choice in the early ‘80s when I was living in Campbell. There was a great deli nearby that made an incredible cross rib roast served on a sour dough roll. One day, I grabbed a bottle of Mouton Cadet that they were selling and had it with the sandwich. Wow! It has been a love affair ever since. The light bulb turned on when I realized that the sandwich was better with the wine and the wine was better with the sandwich. How could two items play off of each other like this and affect the taste of each other?

Vinous: I recall it clearly — 1988 at the Napa Valley Wine Auction. Our hospitality event took us to Spottswoode and barrel samples of the 1985 Estate Cabernet. Up until then, I was primarily a white wine drinker. Starting with the bouquet and then the first taste, this wine changed my perception of and appreciation for red wine.

Noelle: Our beer loving family awoke to the pleasures of wine in 2001 during a family reunion in Tuscany. It was a magical week-long experience, with 21 of us ranging in age from 8 to 81, sharing the beauty of Tuscany and all it has to offer, not the least of which were the delicious, no name wines served at every lunch and dinner.

Pedro: I’m not sure if I experienced a specific moment that made me recognize the beauty and wonders of wine. I began working with my father in the grape fields at 12 years old and don’t know that I recognized the essence of wine through its gentle aromas and delicate flavors. But, right away I did recognize wine was very special. Why else would farm workers work so hard year-round in the field and people come to Napa Valley from around the world to enjoy this magical liquid we call wine?