Rabbi Mendel Agranovich
We have reached a central topic concerning the prohibition of cooking: reheating food on Shabbat.
Whenever we want to reheat something, we have food that is already cooked but has now cooled down (if the food was not fully cooked before Shabbat and was removed from the flame, it may not be cooked further under any circumstances—see our previous article). We want to heat it, and we need to determine whether heating cooked food constitutes cooking. In other words, can there be “cooking after cooking”?
The Talmud discusses an example of a medicine used in those days, prepared from overcooked chicken, which the recipe required to be kept in hot water for a long time. It is clear that the water was changed, including on Shabbat. This means that the chicken continued to be treated with heat during Shabbat. It is important to bear in mind that:
– the water used for this had been heated before Shabbat;
– the pot containing the chicken was not over a flame, so changing the hot water in it violated neither the prohibition of cooking water nor the rabbinic prohibition of returning something to the flame after it had been removed (we will discuss this law later).
This example is the source of our understanding that once food has been fully cooked, continuing to treat it with heat does not constitute cooking. In other words, “there is no cooking after cooking.”
The Talmud also states that cold food cooked before Shabbat may be heated on Shabbat. In other words, “there is no cooking after cooking” even when we take cold food and heat it. The source for this is the following law: any food immersed in hot water before Shabbat may be immersed in it again on Shabbat. This law is stated without specifying whether the food we wish to immerse in hot water is cold or hot. From this, the sages conclude that cold food may also be reheated.
If we recall that cooking is the process of treating materials with heat, or the process by which a housewife produces cooked food (see the previous article), the reasoning behind this law becomes clear: the food is ready and the material has been treated, so heating it adds nothing fundamental. But can we always say that heating food that has cooled down is insignificant?
The sages disagree on this subject: Rashi, Tosafot, the Rosh, and the Tur hold that this applies only to dry food, while liquids that have cooled down may not be heated, since temperature is a crucial criterion for them (imagine cold broth), and much of the effect of cooking has been undone once the liquid has cooled. The Rambam, Rashba, and Ran, in turn, hold that the rule “there is no cooking after cooking” applies to liquids as well, since the criteria for cooking are absolute and depend not on how much this heating matters to a person, but only on whether the material has already been treated with heat.
It should be noted that Rashi’s starting point is a passage in tractate Shabbat (34a), which states, concerning an already cooked dish, that there is a concern that it will be placed over a flame and brought to a boil on Shabbat. At first glance, this contradicts another passage on folio 145b, quoted above: there it states that there is no cooking after cooking. Here, however, it states that there is a concern that something already cooked will be brought to a boil on Shabbat. How can this be reconciled?
The answer is simple: folio 145b discusses dry food, while folio 34a discusses liquid food. This is the basis for the position described above. The Rashba and other commentators explained that the concern about boiling is not a concern about cooking a dish that has already been cooked. Rather, it is a concern that a fire will be kindled for this purpose, violating the prohibition of kindling a fire rather than the prohibition of cooking.
This disagreement is reflected in the views of Rabbi Yosef Karo (the Shulchan Aruch) and Rabbi Moshe Isserles (the Rema). The Shulchan Aruch ruled in accordance with Rashi’s opinion, while the Rema’s opinion sparked heated debate because of wording that expressed only disagreement with Rabbi Karo’s view and stated that food may also be reheated if it has cooled below the temperature at which “the hand recoils,” but has not cooled completely and is still considered warm (hot) by people. Thus, according to the Rema, liquid food that has cooled down may not be reheated.
The following question arose among the sages: how should the Rema’s statement be understood? The authors of Magen Avraham and Pri Megadim held that if the food has cooled completely, the Rema agrees with the author of the Shulchan Aruch that reheating it is prohibited by Torah law. The Chazon Ish and Rabbi Moshe Feinstein, in turn, held that the Rema accepted the opinions of the Rambam, Rashba, and Ran, and that the prohibition of reheating food that has cooled completely is merely a stringency. This is a compromise with the author of the Shulchan Aruch.
In any event, according to all opinions, liquid food that has cooled completely may certainly not be heated—according to Magen Avraham, this is prohibited by Torah law [and this is also evident from the Mishnah Berurah (section 257, subsection 5, comment 28)]. According to the Chazon Ish and Rabbi Moshe Feinstein, it is prohibited at least because of the accepted custom to heat only food that has not cooled completely.
Practical conclusions:
– dry food may be reheated on Shabbat [not over a flame, even a covered one (see the note at the end of the article)];
– according to the Shulchan Aruch, liquid food may be reheated if it has not cooled below 45 degrees. According to the Rema, it may be reheated if a person still perceives it as warm (the ruling of Rabbi Moshe Feinstein, Igrot Moshe, Orach Chaim, section 74, subsection 34) [it is important to note the following: according to Rabbi Feinstein, the upper limit of the temperature at which “the hand recoils” is 71° (rather than 80°, as was mistakenly stated in the previous issue), and therefore, according to the Shulchan Aruch, liquid food that has cooled below this temperature may not be reheated; this is relevant to everyone who does not follow the Rema’s opinion];
– liquid food that has cooled completely may not be reheated.
What is meant by dry food?
For example, schnitzel, a cutlet, or boiled potatoes—that is, a dish without liquid or sauce, even if it feels wet (for example, potatoes after they have been removed from the water in which they were boiled; see Mishnah Berurah, section 318, subsection 32).
Even a dish whose main component is “dry,” with only a small portion consisting of sauce or gravy, may not be reheated on Shabbat (for example, a pot roast).
What if we need to reheat only the meat from the pot roast?
In this case, two additional questions arise.
1. Removing meat from sauce or gravy for reheating constitutes selecting what is fit to eat (the meat) from what is unfit (the gravy, since it may not be reheated) [Orchot Shabbat, chapter 3, subsection 31]. At first glance, this does not constitute immediate use directly after selection. Such an action is permitted according to the Mishnah Berurah and Rabbi Shlomo Zalman Auerbach (Orchot Shabbat, chapter 3, subsection 56, note 55). According to the Chazon Ish, it is prohibited if more than half an hour passes between the act of “selection” and eating the reheated food (a response in a letter to Rabbi E. Dushinsky) [more on this in future articles].
2. Small remnants of gravy or fat that cannot be separated become liquid when heated. In the Mishnah Berurah, the Chafetz Chaim writes that if they remain visible after heating, heating such food is prohibited. If they are absorbed, however, it is permitted.
The following advice can therefore be offered: if you have chicken with a small amount of congealed fat, place it together with rice or another dry side dish to reheat. The fat or gravy will then be absorbed into it, and the problem will thus be resolved.
An important practical note:
Everything discussed above may be done only if the following rabbinic prohibitions are not violated:
1. the prohibition of reheating food over a flame;
2. the prohibition of returning something to the flame after it has been removed on Shabbat.
A question arises: haven’t we just been discussing how to reheat food on Shabbat? What, then, is the rabbinic prohibition? It means that placing even dry food over a flame to reheat is prohibited because it “resembles cooking.” Our sages therefore ruled that food may not be reheated in the same way as on weekdays.
There are two accepted ways to reheat food on Shabbat:
1. Place the dish of food on top of a pot that has been over the flame since Friday, as a “second tier.” This is permitted according to all opinions, since no one reheats food this way on weekdays.
2. Place the dish of food on an empty, inverted pot or plate, which in turn rests on a Shabbat hot plate or a metal sheet covering the flame (a blech). This is customary in many homes and is permitted according to Rabbi Shlomo Zalman Auerbach and Rabbi Shmuel Wosner (Orchot Shabbat, chapter 2, subsection 66, note 113). According to the Chazon Ish (section 37, subsection 9), this method is prohibited. A detailed explanation will follow in future articles.