10. Davar Gush

As we stated in section 7, a kli rishon can cook anything, a kli sheni can cook only kalei ha-bishul, and a kli shlishi cannot cook at all. However, the poskim disagree regarding the status of a davar gush (hot, solid food).

Some maintain that the general rules of vessels apply in this case as well, and once a davar gush is moved to a kli shlishi it cannot cook anything that is placed upon it. This is the opinion of the majority of poskim (Rema; Vilna Gaon; Pri Megadim; Ĥatam Sofer; Nishmat Adam).

However, some poskim are stringent and rule that the aforementioned principles apply only to liquids or soft foods that come into complete contact with the walls of a pot. Such foods can no longer cook if they are transferred from a kli rishon to a kli sheni and from a kli sheni to a kli shlishi. But chunks of solid food – pieces of meat, kugel, potatoes, or clumpy rice – retain their heat even when transferred from vessel to vessel, as the walls of the new vessels do not have a strong cooling effect on solid food. Therefore, as long as these foods remain at a temperature of yad soledet bo or hotter, they are able to cook, no matter how many vessel transfers they have undergone (MA; MB 318:45).

In practice, since this relates to a Torah prohibition, it is appropriate to be stringent. However, if one is in doubt about whether cooking would be involved, one may be lenient even le-khatĥila. Therefore, if one can touch the piece of food and it is doubtful whether it is yad soledet bo, there is no need to worry that it will cook (see section 4 above). Even if it is clear that it is still yad soledet bo, one may put previously-cooked cold gravy on it, since some maintain that ein bishul aĥar bishul applies to liquids as well (see section 5 above). Similarly, one may salt the food, since salt can only be cooked in a kli rishon that is on the fire (MB 318:71). Additionally, one may place pickles or raw vegetables on a hot piece of kugel or meat, because one does not intend to cook them.

In contrast, one may not sprinkle raw spices like paprika and pepper on a hot piece of meat or kugel, as there is a benefit to the spices cooking – it enables their taste to be absorbed more effectively into the food. Therefore, before adding spices to a hot dish, one should wait until it has cooled off enough that one can touch it.[9]

[9]. Regarding the laws of kashrut, some are stringent in the case of a davar gush if it is still yad soledet bo. This is the approach of Isur Ve-heter, Maharshal, Shakh, Pri Ĥadash, and Pri Megadim. Opposing them are Rema, Vilna Gaon, and Ĥatam Sofer, based on Tosafot and Ran, who insist that a davar gush is no different from other foods. Others maintain that we are stringent for kashrut purposes because a davar gush can absorb tastes; but for Shabbat purposes, since a davar gush cannot cook, there is no prohibition. This is the approach of Minĥat Yaakov 61:45; Pri Megadim, Mishbetzot Zahav, YD 97:14. Furthermore, Igrot Moshe OĤ 4:74, Bishul 5; R. Ovadia Yosef, Halikhot Olam, 4:12; and Or Le-Tziyon 2:30:16 state that one may be lenient. However, MA 318:45 is stringent concerning Shabbat as well as kashrut, as are MB 318:118 and SSK 1:64. Since this disagreement relates to a Torah prohibition, it is proper to defer to those who are stringent, but in practice one need be stringent only regarding spices. In a case where there is an additional doubt, one may be lenient on the basis of the principle of twofold doubt. Similarly, one may be lenient regarding putting butter on a very hot solid, as the Igrot Moshe states, since butter is pasteurized, and pasteurizing is the equivalent of cooking. (SSK ch. 1 n. 198 disagrees, however.)