15 - Bishul Achar Bishul of Liquids

The Laws of Cooking and Warming Food on Shabbat (by Rabbi Mordechai Willig)

Chapter 4: Partially Cooked

A. The Views of the Rambam and the Rashba Concerning When Ein Bishul Achar Bishul Can Be Applied

The Rambam maintains that a person is exempt in the case of bishul achar bishul only if the food had been fully cooked before Shabbat; since it is already fully cooked, the subsequent reheating does not improve the food and thus is only rabbinically prohibited. In the same sentence, the Rambam states an exemption in the case of cooking food which does not need cooking , for the same reason, namely, that there is no improvement: "One who cooks on the fire something that is fully cooked or something that does not need cooking at all is exempt (patur)."¹

The Rashba² applies the principle of ein bishul achar bishul to food that had been partially cooked. We have seen³ that the melakhah of cooking is defined as cooking food to the level of kema'achal ben derusa'i. Ben Derusa'i was a bandit who ate his food only partially cooked: half cooked according to the Rambam⁴ and one third cooked according to Rashi.⁵ Since, when the food reaches kema'achal ben derusa'i, the food is halakhically cooked, one who performs a subsequent cooking is exempt according to the Rashba, even though the food is improved by that act, and the action is therefore permissible. Thus, while the Rambam only applies ein bishul achar bishul to food that is fully cooked and can no longer be physically improved through cooking, the Rashba applies ein bishul achar bishul even when cooking still enhances the food.

B. Cooking: A Halakhic Change or a Physical Change?

The Radvaz⁶ writes that according to the Rashba, one who cooks food which is eaten raw is exempt. After all, if food which only a bandit eats is exempt from the prohibition of cooking, how much more so food which anyone can eat raw. This proof, however, is flawed. In contrast to the Rambam, who focuses on the physical changes to the food, the Rashba understands ein bishul achar bishul in a halakhic sense, not in a physical one. In his view, food that has undergone a halakhic definition of cooking cannot be cooked again. However, if the food had not been cooked, one might indeed violate bishul even if ti can be eaten raw. Nevertheless, the point may still be true that the Rashba requires a need for physical improvement as well , and thus exempts food which is eaten raw. The Peri Megadim⁷ questions whether the principle of ein bishul achar bishul applies to food which had been cooked in the sun, a process which is not considered cooking halakhically,⁸ despite its physical effect on the food. In theory, this distinction may make cooking in the sun a test case for the difference between the views of the Rashba and the Rambam. According to the Rambam, one should be exempt for a second act of cooking if cooking in the sun is physically equivalent to cooking on the fire, since there is no subsequent improvement with that second cooking. According to the Rashba, however, one might indeed violate bishul for re-cooking food that was cooked in the sun, since there was no previous halakhic cooking. However, if the Rashba requires that there be room in the definition of cooking for physical improvement as well, then one would be exempt from subsequent cooking. This is the conslusion of the Peri Megadim.

This issue is relevant to food cooked in a microwave oven, which has no fire and may be like cooking with the sun.⁹ According to the view of the Rambam, one who takes food cooked in a microwave and subsequently reheates it on Shabbat would be exempt, which the Rashba's position is unclear. One might indeed violate bishul for re-cooking food that was cooked in a microwave since there was no previous halakhic cooking. However, if the Rashba requires that the definition of cooking includes physical improvement as well, then one would be exempt from subsequent cooking of food cooked in a microwave.

Despite his focus on the halakhic status rather than the physical status of the food, the Rashba must concede that if the actual effect of the first halakhic cooking disappears, a second cooking would be in violation of bishul. This is evident from the law of melting metal.¹⁰

C. Ran and Rashba: Cooking is a Halakhic Change

The Ran¹¹ cites a stringency in the name of Rabbenu Yonah: One may not pour water from a kettle into a stwe to prevent the stew from drying up. If the water is hot, i.e., yad soledet bo, and the soup in the stew is not, or vice versa, the hot liquid has cooked the one that has cooled. Rabbenu Yonah's position proves that bishul achar bishul applies to soup as well as water, in contrast to view of the Peri Megadim mentioned above.¹²

Rabbenu Yonah posits further: Even if both liquids are hot, once the water leaves the kettle and is being poured into the stew, the water may lose its halakhic status of food in a keli rishon, a pot that was in the fire. Thus, when it enters the pot of stew, the water is subject to being cooked, and bishul is violated. This change in status is purely halakhic; the water is physically the same when it is inside the kettle and when it is outside of it. Like the Rashba, apparently, Rabbenu Yonah views the principle of ein bishul achar bishul from a halakhic perspective, not a physical one.

The requirement of yad soledet bo for soup to be considered cooked is intructive. After all, soup is unlike water which is "cooked" when merely heated; soup changes meterially during the procedure. It could thus have been thought that even when the soup cools off, it maintains its status of "cooked" and should not be subject to further prohibitions of bishul.¹³ According to Rabbenu Yonah, however, from a halakhic perspective, soup is apparently cooked in two senses: it is both physically changed and heated. If it loses its status of "hot" (halakhically, when the soup is no longer at the temperature of yad soledet bo or no longer in a keli rishon), it is prohibited to reheat it even though the physical changes remain, since reheating cooled soup is also considered an act of cooking.

D. Summary

When the principle of bishul achar bishul may be applied is a subject of dispute between the Rambam, who applies it only to fully cooked food, and the Rashba, who applies it even to food cooked kem'achal ben derusa'i. This dispute may stem from the distinction between cooking as a physical change (Rambam) and cooking as a halakhic change (Rashba and Ran). The distinction may determine whether one has violated bishul when reheating food previously cooked in a microwave (since only a physical change, not a halakhic change, occured in the microwaving of the food), and whether one has violated bishul by pouring hot water into hot stew (where only a halakhic change in the water, but not a physical change, has taken place). Even the Rashba, however, may understand cooking as a halakhic change in addition to a physical change, not instead of a physical change. In line with the positions of the Shulchan Arukh and Rama, the stringencies of both views should be followed.

Chapter 5: The Rama's Compromise

A. Reheating Soup

As we have seen, there is some question as to the permissibility of reheating soup. The Rama¹ quotes the two opinions about bishul achar bishul with regard to soup. The first requires the soup to be hot, i.e., above the temperature of yad soledet bo, for reheating to be allowed. The second permits reheating cold soup. The Rama concludes with a compromise: "It is customary to be lenient if it did not cool off completely." How do we understand this position? Does the Rama start with the premise that reheating any cooled liquid is forbidden, and add a leniency that soup that is still somewhat warm may be reheated? Or does the Rama start with the premise that reheating any cooled liquid is permitted, and add a stringency that the liquid must still be somewhat warm?

B. The Magen Avraham's Understanding of the Rama

The Magen Avraham² assumes that if the soup cooled down completely, it is prohibited by Torah law to reheat it. This is the simple reading of the Terumat HaDeshen³ who considers reheating completely cooled soup an av melakhah, an act prohibited by Torah law. If, however, the soup is fit to be eaten without reheating, comparable to ma'achal ben derusa'i, no violation of bishul occurs. The Terumat HaDeshen quotes this ruling from the Mordechai,⁴ Hagahot Maymaniot⁵ and the Semag.

At first glance, this stnce is based on the Rashba, who permits cooking food which had reached the point of ma'achal ben derusa'i.⁶ However, the Semag rules like the Rambam, that ein bishul achar bishul applies only if the food has been fully cooked. Nevertheless, the Semag allows reheating soup which had been hot, but has parially cooled off, and is now comparable to ma'achal ben derusa'i.

The question of how the Semag can simultaneously hold that ein bishul achar bishul applies only to fully cooked food, but yet permit the reheating of partially cooled soup, can be resolved based on our earlier analysis.⁷ Those who prohibit bishul achar bishul for liquids view the original heating as having diappeared. They rule that the original cooking as having disappeared. They rule that the original cooking has disappeared as soon as the liquid is no longer halakhically hot, i.e., yad soledet bo. The Semag maintains that as long as the soup is still fit to be served as hot food, even if it is cooler than yad soledet bo, the original heat has not disappeared. The soup is still considered fully cooked, and, therefore, may be reheated.

This is the Rama's compromise as understood by the Magen Avraham, namely, that partially cooled soup is still considered cooked and may be reheated. The Rama allows the reheating of cholent chich had