"After two thousand years of evolution in almost every country and culture, Jewish cuisine is the cuisine of the world. But if Jewish cooking is universal, what makes a dish peculiarly Jewish? Following Halakah (Jewish law) meant that Jews could not simply adopt all of the dishes of their new homelands. Since the dietary laws excluded such foods as pork, lard, and shellfish, and the mixing of milk and meat, Jews found substitutes for these items. In addition, the Jewish lifestyle - shaped by Shabbath prohibitions, holiday traditions, Torah precepts, and life-cycle events - produced uniquely Jewish dishes that, although based on local foods, often manifested similarities to Jewish dishes from other locales. For example, all Jewish communities incorporate foods mentioned in the Bible - such as almonds, apples, dates, raisins, and honey - as symbolic ingredients in assorted festival dishes. Since many dishes were prepared ahead to be served cold on the Sabbath, vinegar was commonly added as a preservative and often sweeteners or raisins to counter the acidity of the vinegar. As a result, sweet-and-sour dishes proliferated in the Jewish culinary repertoire. And Jews commonly affixed their own special touches to local dishes, such as adding garlic (an item despised by many cultures) and onions, thereby creating extra layers of flavor." Marks, G., "The World of Jewish Cooking," Simon & Shuster, 1996, p. 3.
To learn more, why not drop in at: rec.food.cuisine.jewish.
Obviously, you don't need to be Jewish to enjoy the food.