Cute article in the Forward yesterday about the ubiquity of schnitzel in Israel. It gets into the reason offered for why it became so popular. Citing (fellow TA Baltimore grad!) Gil Marks's new Encyclopedia of Jewish Food:
immigrants from central Europe to Palestine introduced schnitzel to early kibbutzim during the beginning of the twentieth century. The simple dish that could be made in a pan (few people had ovens at the time) became a common shabbos meal, as it could easily be made the day before it was served.
Fast forward to the 1940s, the War of Independence, mass immigration and food shortages, marked by rations and regulations. Marks says that it was during this period that “The new Ministry of Absorption taught the diverse housewives from across the globe how to prepare various simple recipes made from readily accessible, inexpensive items,” including schnitzel and the tradition stuck
And another theory:
On her website Israeli food writer Janna Gur explains that “In Israel, [schnitzel] is made of chicken or turkey breast — an invention born out of necessity, when veal was nonexistent and poultry was government-subsidized and more readily available.”
I believe there is merit to all these theories, and it certainly explains why chicken and turkey became popular, but do not seem to go far enough to explain why schnitzel in particular. I think I know why, and the answer is rooted in halakha.
Schnitzel is not merely a classic Shabbat food- it is served primarily at Shabbat lunch. Other traditional Shabbat lunch foods include cholent and cold cuts. The common denominator is that they can all be eaten in their optimal form on Shabbat afternoon.
In the Ashkenazic tradition, foods that are "wet" may not be reheated on Shabbat, as this reheating continues and improves the cooking process. On Friday night there's little problem, as food left on a warming tray from before Shabbat will be perfect a couple hours later. Food left on the same warming tray overnight will turn gross.
So Shabbat lunch fare is limited to foods that can be eaten cold (like cold cuts), foods that can be very slowly cooked (like cholent), and foods that are so dry that they can be reheated on Shabbat without any problem (like schnitzel). So the popularity of schnitzel was born of economic but also halakhic necessity!
There's another popular Israeli food that has a similar genesis as a ubiquitous culinary artifact - sunflower seeds. I believe that they were first adopted by Israeli smokers (Lord knows they were in abundance back in the day) who needed a fix on Shabbat, when they wouldn't light up. The fingers-to-mouth motion of Israeli-style seed-eating sufficiently mimics smoking for nicotine addicts to make it through the day.