| (zin-fan-del) The Zinfandel is a red grape variety of wine. Classically, this wine is grown in California. The origins, while shrouded in mystery have recently (Spring 2002) genetic analysis has shown that the Zinfandel and the Primitivo are genetically identical within the testing sensitivity (and also related to some other European wine varieties). This said, the California Zinfandel grape did not likely originate in Italy and more likely came from Croatia (the Crljenak kastelanski grape) that is today thought to be on the verge of extinction (only 20 vines are known to exist).
Before you go out and get a Primitivo (or heaven forbid, an Italian so-called Zinfandel) wine thinking that it is the same as a Zinfandel, you should realize there are a number of other factors that go into the flavor of a wine besides the actual grape. These factors include the style of wine-making, the desired flavor, growing season length, climate, cultivation time. This combination of factors can drastically change the profile of the wine (for example the California Zinfandel is 15% to 16% alcohol while the Italian Primitivo is closer to 13% to 14% alcohol). Another example is the harvest time resulting in different flavors being expressed in the final wine.
Historians now believe (but, by no means are certain) that the grape was imported to the United States from a vine cutting in Vienna sometime in the 1820s. Other cuttings likely made their way to Italy and other European destinations. The first occurrence of the Zinfandel name was in 1832 when a Boston nursery owner (Samuel Perkins) advertised "Zinfandel for Sale". In the 1850s, the Zinfandel grape was introduced to California and paticularly the Sonoma and Napa counties. Also in the 1850s, the Zinfandel wine becomes popular in the New england and the wine boom in California from 1878 to 1889 was fueled by the Zinfandel. Today, the Zinfandel grape is the most planted grape - in more than 50,000 acres in California.
The wine itself has colors that run from blush to a tannin flavored opaque. The red Zinfandel wine is described as big and robust with a concentrated flavor. Many times, the Zinfandel has some spices such as a clove note (from eugenol found in oak barrels), added to it that are rarely found in other wines (this comes from piperidene). The white Zinfandel wine is the same grape though it goes through a different process and is picked earlier than the other Zinfandel grapes and the skins are separated during the crushing and fermentation (within a few hours) process only leaving a hint of its red heritage. These wines also have less alcohol than their red cousins. Being picked earlier, the grapes are also more acidic so the wine is made in a sweeter style to balance out the acid taste often with fruit flavors added (the most common of them is strawberry). The essence of the white Zinfandel is often described as mellow yet crisp, fruity and refreshing and is best consumed within a year or two of the vintage year (it is not a wine to let age).
A selection of wine reviews for various Zinfandels:
http://www.zinfandel.org/
http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2002/07/31/FD69286.DTL | 
