Passover is the annual holiday in remembrance of the Exodus, when the Jews fled Egypt and Pharaoh's oppressive rule. For the first evening or two evenings of Passover, a religious meal, called a seder, is served.
During this meal, each person at the dinner table is poured four glasses of wine, which, according to some religious texts, represent sanctification, deliverance, redemption and release, respectively. (A separate glass, which is not drunk, is traditionally poured for the prophet Elijah.) During a seder, only kosher wines can be consumed.
"Kosher" is a Yiddish term, derived from the Hebrew word for "fit " or "proper." When applied to winemaking, it means that the wine has been produced in accordance with Jewish dietary laws, following strict rules of preparation under the supervision of a rabbi. The label will typically bear the statement, "This wine is certified kosher for Passover," and may also carry the symbol of one of the kosher-certifying organizations.
According to Royal Wine Corp., maker of Baron Herzog and other kosher wines, kosher winemaking must adhere to three standards: All winemaking equipment must be rigorously cleaned and used exclusively for kosher wines; only certified kosher yeast and fining agents can be used; and only Sabbath-observant Jews can handle the grapes, from crush to serving.
However, some kosher wines are also mevushal, which means that they have been subjected to heat as part of a ritual process that protects their religious integrity. These wines can be handled by non-Jews and remain kosher.
Unfortunately, heating a wine can also harm its flavor, so in recent years, many kosher wineries have been using flash-pasteurization to make mevushal wines. In this process, the wine is quickly brought to about 185 degrees F, then quickly brought back down. The entire process lasts for only a few seconds.
Royal Wine Corp.'s flash pasteurization process seems to have little effect on the wine's quality, judging by the very good to outstanding ratings that the company's Herzog Special Reserve wines have earned from Wine Spectator. The company cites a study, performed by the University of California at Davis, which determined that a wine would have to be heated for 10 times longer than the duration of the average flash pasteurization before a taste difference would occur.