Saturday night at sundown is the start of Passover or Pesach, the festival commemorating the Jewish exodus from Egypt and their liberation from slavery there.

Part of the celebration is the ritual Seder dinner, in which four cups of wine are drunk after blessings, while a fifth cup is traditionally left for the prophet Elijah.

The wine drunk must be kosher for Passover, stricter requirements than even normal kosher, or pure, wines.

Traditionally, kosher wines in the United States were made from the grapes like Concord, Catawba and other native American varieties, and most American Jews grew up drinking sticky sweet Mogen David and Manischewitz during the ceremonies.

Many people, in fact, think kosher wine has to be made from sweet Concord grapes. Clearly, that’s not true, for those grapes didn’t even grow where the Israelites lived, and we can be assured that Jews thousands of years ago (including Jesus at the Last Supper, which was a Passover Seder), weren’t drinking Mogen David.

In truth, kosher wine, including that suitable for Passover, can taste like any other wine. Although it has to be made following certain rules and regulations, its quality depends on the grapes and winemaker just as with any other wine. Only one optional step during winemaking might potentially compromise the flavor, and modern technology has minimized that possibility.

Kosher wines are made in almost all grape-growing areas. Naturally Israel, but also in France, Spain, Italy, Australia, Chile and South America as well as the United States.

Since Jews are prominent throughout the wine world, they make many kosher wines that most people might never notice. These include the Rothschilds, arguably the most respected wine family in the world, and the Skalli family that owns St. Supéry and produces Fortant de France wine. Pommery, Laurent Perrier and Heidsdick all produce kosher Champagne, too.

Here in Napa Valley, there’s only one kosher winery, Ernie Weir’s Hagafen Cellar, although Jeff Morgan and Leslie Rudd produce the kosher Covenant Cabernet at the Hertzog facility in Santa Barbara.

Hagafen lies on the Silverado Trail just north of Napa, and has a friendly tasting room. You can find a coupon for free tasting on its Web site at www.hagafen.com.  

Both Covenant and Hagafen avoid much discussion of the kosher nature of the wines in general promotion, preferring to be judged just against other Napa wines.

That brings up the reason and nature of kosher wines. Wine holds a special place in Jewish tradition. It is considered to have spiritual significance and the blessing over a glass of wine — the Kiddush — regularly marks the beginning of religious rituals.

What makes a wine kosher? Fundamentally, it must be made by Sabbath-observant Jews, those who strictly observe kosher dietary laws. In addition, products such as yeasts from grains or animal-based fining agents are prohibited by tradition, and would compromise the ritual essence of the wine.

Most kosher wineries pasteurize the wine so it can no longer ferment naturally. This makes it meshuval and it can be handled by gentiles.

Obviously, raising wine to a high temperature can damage its flavor, but winemakers claim that flash pasteurization systems, which raise the temperature and quickly lower it, fulfill the letter of the Jewish law without compromising the flavor. It’s pretty hard to find examples of the same wine that’s been through this process. I must admit that I’ve detected a slight cooked flavor even in some fine kosher wines, but not all

So the good news is that if you are invited to a Seder, you don’t need to take Maneschevitz. You can find a wide range of quality kosher wines, including some from Napa like the $90 Covenant as well as the aforementioned Champagnes. A list of many can be found at www.kosherwine.com, and there’s even a kosher wine “magazine”  at www.kosherwinereview.com.