by R. Daniel Mann
Question: In our home, the health concerns of some and the taste concerns of others clash in regard to salt in our food. If I cook with less salt, may people add salt to their soup or cholent on Shabbat?
Answer: We will discuss the issues that impact the different permutations of the question.
The gemara (Shabbat 42b) cites three opinions regarding cooking salt in comparison to cooking other spices (which occurs in a kli rishon but not a kli sheini). 1. It occurs only in a kli rishon on the fire; 2. It is like other spices; 3. It occurs even in a kli sheini. The Shulchan Aruch (Orach Chayim 318:9) rules like the lenient opinion (only forbidden on the fire), which would solve your problem. However, the Rama cites the opinion that salt cooks even in a kli sheini and praises those who are machmir. Therefore, we will seek other grounds for leniency.
First, we must survey the three modes of salt production: 1. mining underground; 2. cooking seawater so that only salt remains; 3. evaporating seawater in the sun and drying the moist salt with hot air. #3 is the standard in Israel.
If #2 is done, we can apply the rule that the prohibition of cooking does not apply to solid foods that were already cooked. This does not guarantee permissibility, as some claim that since salt becomes liquefied during its usage, it is treated like a liquid, for which recooking is likely forbidden (see Mishna Berura 318:71). Even regarding definite liquids, the prohibition might only be a chumra (Igrot Moshe, OC IV:74.5, based on Rama OC 318:15). Therefore, regarding such salt, the case for leniency is very strong.
If system #3 is used, the case is arguably weaker because hot air accomplishes baking as opposed to cooking, after which Ashkenazim generally forbid cooking (see Shulchan Aruch and Rama ibid. 5). On the other hand, this too is a matter of machloket (many Sephardim do not view cooking as a problematic addition for a baked food – see Yalkut Yosef, OC 318:61), and the minhag is to be stringent regarding a kli rishon and kli sheini, but lenient in a kli shlishi (Mishna Berura 318:47).
What are the statuses of the cholent and the soup? There is an unresolved machloket whether food that was ladled from a pot to a bowl is considered a kli sheini or kli shilishi (ibid. 87). If the cholent contains chunks of food and not much gravy, it is considered a davar gush (a food that comes in a chunk). There is yet another unresolved machloket whether a davar gush sitting in a kli sheini is treated like a kli sheini, or perhaps a kli rishon because the walls of a kli sheini do not cool a solid like a liquid (ibid. 45). The machmirim treat a davar gush like a kli rishon even in a third utensil (Orchot Shabbat 1:63). Not only is it difficult to combine all the stringencies (salt cooks off the flame, cooking after baking is forbidden, we are machmir by davar gush), if it is dry, it is baking, not cooking.
Regarding significant liquid, we posited in the past that a mixture of liquid and chunks (e.g., vegetable soup, liquidy cholent) is not treated as a davar gush. Therefore, cholent ladled into a serving bowl and soup in bowls are a safek of kli sheini or kli shlishi, which are both permitted for baked things (Mishna Berura 318:45).
If the salt has not been heated, leniency would have to rely on the (main) opinion that salt does not cook easily or the possibility it is in a kli shlishi, in which case there may never be problems of cooking (Igrot Moshe, OC, IV 74:15). Even the stringent about kli shlishi would probably permit if for salt (see Orchot Shabbat 1:41). When there is a safek between kli sheini and kli shlishi, it is slightly more problematic.
Therefore, while we cannot claim unanimity in all the permutations, in the great majority of cases, the consensus is to permit putting salt in utensils with hot food other than the cooking pot (see Shemirat Shabbat K’hilchata 1:58; Igrot Moshe ibid. 5 & 17). In borderline cases, helping establish workable solutions for family health is a factor that strengthens the case for leniency.