When the Jews asked Sichon, king of the Amorites, for permission to travel through his territory, they said1: "You shall sell me food for money, that I may eat; and give to me water for money, that I may drink."

Our Sages interpret this to mean that just like water is not changed by the heat of fire, so too the only food that one may purchase from a non-Jew is one that was not changed by the heat of fire. This verse supports the Rabbinic prohibition against eating food that was cooked entirely by non-Jews.2

By forbidding Jews from eating food cooked by non-Jews, our sages intended to create a social barrier between Jews and non-Jews in order to prevent intermarriage. An example of social dining which led Jews to intermarry is found in the Torah3: "Israel settled in Shittim, and the people began to commit harlotry with the daughters of the Moabites. The [daughters of Moab] invited the people to the sacrifices of their gods, and the people ate and prostrated themselves to their gods."

Some say that the reason for this prohibition is also to prevent a Jew from becoming accustomed to eating food prepared by non-Jews, which could eventually lead to eating non-kosher food.4

The prohibition is called bishul akum, which literally means: "cooking of a pagan." Yet the prohibition applies to all non-Jews, even if they are not pagans, as the prohibition against intermarriage applies to all non-Jews.5 Food that was cooked by a Jewish person (see the details of this below) is called bishul yisrael ("cooking of a Jew").

The prohibition applies even if all of the ingredients used and the manner of preparation are kosher.6

Following is a compilation of some of the laws relating to this topic.

The prohibition of bishul akum does not apply to all foods:

  • Any food that is regularly eaten while raw is not included in the prohibition. If a non-Jew were to cook carrots, apples, or any other fruit or vegetable that is eaten raw, it is permissible for a Jew to eat it (assuming that it is 100% kosher).7
  • A food that is considered locally to be low-status (not "food that would be served at a king's table") is not included in the prohibition.8 For example, sardines.9 Since such a food is unlikely to be served when one person invites another for a meal, permitting its consumption would not lead to close friendships.10
  • Some halachic authorities maintain that for this reason potato chips do not need to be bishul yisrael.11 Others maintain that since potatoes themselves are generally a respectable food, even potato chips must be bishul yisrael.12
  • Most authorities are of the opinion that coffee does not have to be bishul yisrael.13 Some authorities are strict regarding instant coffee.14
  • If some ingredients in a dish are fit for a king and some are not, or some are edible raw and some are not, the food is designated according to the main ingredient.

Food that is bishul akum is forbidden to eat and is considered not kosher. Therefore, if food is cooked by a non-Jew in such way that it is bishul akum, the pot in which it was cooked must be koshered in order for it to be considered kosher and fit for use again.15

Therefore, if there is a reliable kosher symbol on a particular food, this means either that the food is bishul yisrael or that it does not have to be. There are some foods that are subject to differing opinions as the whether they are required to be bishul yisrael or not – such as potato chips, as discussed above, or tuna. In these cases, the kashrut agencies will write "bishul yisrael" on the package if it was actually cooked by a Jew. If the package does not say this, the assumption is that it was not prepared by a Jew and that they are relying on the lenient opinions.

In order for a food to be considered bishul yisrael, it is not necessary for the Jew to cook it from start to finish. It is enough if he actively participates in an integral part of the cooking process. For example, if a Jew places a pot on the fire (or in the oven) and then a non-Jew stirs it, the food remains kosher. Similarly, if a non-Jew places the pot on the fire and then a Jew stirs it, or if a non-Jew lights the fire in the oven or on the stove and the Jew places the food on it or in it, the food is considered bishul yisrael.16

More details:

  • If the only thing the Jew did was light the fire, and the food was then put on the fire by a non-Jew, there are differing opinions as to the status of the food. Rabbi Yosef Karo (the author of the Code of Jewish Law, known as the Beit Yosef or mechaber) maintains that such food is bishul akum. Rav Moshe Isserlis (known as the Rama, author of the glosses on the Code of Jewish Law) considers this food bishul yisrael. In practice, Sephardim follow the opinion of the Beit Yosef, while Ashkenazim follow the opinion of the Rama.17
  • Some authorities maintain that it is sufficient for the Jew to light the fire from which the fire was taken to cook the food. This would mean that if a Jew lit the pilot light of a stove, and then a non-Jew turned on a particular burner and proceeded to cook food on that burner, the food would be considered bishul yisrael. Ashkenazim may rely on this opinion bedi'eved (after the fact), but not lechat'chila (in the first place); Sephardim do not eat this food even after the fact.18
  • For this reason, one must be careful when allowing non-Jewish help to cook. The flame should be turned on by a Jewish person or better yet, the food should be put on the fire or stirred by a Jew.19

If the food is prepared for eating by salting or pickling, these laws do not apply. Food prepared in these ways by a non-Jew may be eaten.20 There are differing opinions regarding steaming. It is better to be strict in this matter.21

Bread Baked by a Non-Jew

The laws of bishul akum only apply to cooked dishes. Baked goods (made of flour from any of the following five grains: wheat, barley, oats, spelt, or rye) fall into a different category. Those that are baked by a non-Jew are called pat akum ("bread of non-Jews").22

Since bread is considered a staple and a necessity of life, the laws concerning pat akum are more lenient than those of bishul akum.23 For example, in certain circumstances, baked goods that were baked commercially (rather than by a private individual) may be eaten.24 In addition, even if a Jew simply increased the heat in an oven, that is sufficient for the baked goods to be considered pat yisrael,25 whereas concerning bishul akum, there are authorities that say that this participation alone is insufficient. Click here for more basic information on pat akum.