1. The Av Melachah

   The 11th of the 39 Melachos of Shabbos is Bishul - Cooking.[1] Included in this Melachah is boiling, frying, baking and roasting.[2] The precedent for this Melachah is the role of cooking in the construction of the Mishkan, where herbs were cooked to produce dyes.

2. The Definition of Bishul

   The term Bishul means to change the quality of any type of substance by subjecting it to the heat of fire.[3] The Melachah applies to both solids and liquids.[4] The cooking process is prohibited whether it softens a hard substance[5] or hardens a soft substance.[6]

3. "Aish" and "Toldos Aish"

   Bishul is prohibited whether done directly with fire - "Aish"[7] or by a substance that has been heated with fire - "Toldos Aish."[8]

   Examples of Toldos Aish are:

   1. Placing a raw egg into a pot of boiling hot water that has been removed from the fire.

   2. Placing food into a hot oven, even though the oven has been turned off.

4. The Level of Bishul Solids

   When is a substance called "cooked"? Once a raw food has been half-cooked so that it is edible - albeit with difficulty - it is considered cooked. This is called "Maachol Ben Drusoi" - after a highwayman called Ben Drusoi who always ate his food in a half-cooked state.[9]

   It must be pointed out that to take a half-cooked food and cook it further is also an act of Bishul, since one is causing a significant improvement to the food.

   To explain:

   Maachol Ben Drusoi is the point at which a raw food is now considered cooked, and the point at which one who did the cooking has transgressed the prohibition of Bishul.[10] Any further cooking from the level of Maachol Ben Drusoi to the level of being fully cooked is also considered Bishul.

   A fully cooked food is not subject to the law of Bishul even if further cooking will improve the food; this is called "Mitztamake Veyofo Lo."

   Liquids

   A liquid that has been heated to the temperature of "Yad Soledes Bo," i.e., a temperature at which one would withdraw one's hand from such a liquid due to the intensity of heat, is considered cooked. Most Poskim agree that Yad Soledes Bo is between 40 and 45 degrees Celsius, or approximately 110 degrees Fahrenheit.[11]

5. Speeding Up the Cooking Process

   To transgress the prohibition of Bishul it is not necessary that one person do the entire cooking process from beginning to end. Even aiding the cooking process in some way or speeding up the cooking process is considered Bishul.[12]

   Examples:

   1. If there were an uncooked food in a pot that was only partially on the flame, which if left untouched would eventually cook, it would be prohibited to move the pot directly onto the flame since this would speed up the cooking process.[13]

   2. One may not return a pot to the stove if the contents are not fully cooked.[14]

   3. It is prohibited to place a lid on a pot that contains partially cooked food. This is because food in a covered pot cooks more quickly. Great care must be taken on Friday night to make sure that the cholent is fully cooked if one wishes to have a look at it. If the cholent would only be partially cooked, placing a lid on the cholent would be an act of Bishul. This would be the case even if the lid were lifted for a moment.

   4. Stirring ("Maygis") a partially cooked food causes the food to be cooked more quickly. One therefore may not stir a pot of partially cooked food whether it is on or off the flame.[15]

   5. Closing an oven door when the food inside is not yet fully cooked.

   From the above examples it is clear that removing food from a pot whose contents are not fully cooked may in some way speed up the cooking process. Therefore, it is strongly advised that all foods be fully cooked before Shabbos so as to avoid an act of Bishul.

6. Warming Food

   Even if a person has the intention of only warming food, he may not place the food in a position where it potentially may be heated to Yad Soledes Bo.[16]

7. Cooking Done on Shabbos

   If one did accidentally cook something on Shabbos, a Rav should be consulted as to the status of the food.

   

Notes:

1. (Back to text) Mishnah Shabbos 7:2.

2. (Back to text) Alter Rebbe's Shulchan Aruch 318:7.

3. (Back to text) The prohibition applies even to foods that are usually eaten in their raw state, e.g., fruits. Any change of status by heat is considered Bishul (Alter Rebbe's Shulchan Aruch 318:24).

4. (Back to text) Included in the prohibition of Bishul are melting metal, wax or tar; or baking earthenware (Alter Rebbe's Shulchan Aruch 318:7).

5. (Back to text) It is however permitted to pour hot water into a plastic cup even though the plastic may soften due to the temperature of the water (Shabbos KeHalachah, p. 27).

6. (Back to text) There is considerable discussion among the Poskim as to whether melting a solid food is considered cooking. Examples of this are melting butter or shmaltz. These dinim will be discussed later in Secs. 4:4-4:6.

7. (Back to text) This includes both gas, electric and microwave cookers. One may however cook using direct heat from the sun, but one may not cook in something that has been heated by the sun (Alter Rebbe's Shulchan Aruch 318:7).

8. (Back to text) Shulchan Aruch, ibid.

9. (Back to text) To be precise, the Alter Rebbe's Shulchan Aruch 253:13 rules that even if it is one-third cooked, it is already considered cooked.

10. (Back to text) Before the food has reached the level of Maachol Ben Drusoi, no Bishul has been done; however it should be pointed out that it is still prohibited to place uncooked food on a flame and remove it from the flame before it reaches the level of Maachol Ben Drusoi. The reason for this is that Chazal were worried that one may forget to remove the food from the flame and thereby transgress the prohibition of Bishul (Alter Rebbe's Shulchan Aruch 318:24).

11. (Back to text) Shabbos KeHalachah, p. 24.

12. (Back to text) Alter Rebbe's Shulchan Aruch 318:10. Shabbos KeHalachah, p. 194.

13. (Back to text) Even if a blech was in use, it makes no difference. The issue here is of speeding up the cooking process of this uncooked food (Shabbos KeHalachah, p. 235).

    An interesting example of this case would be cholent made with chicken bones. Many people like to chew the bones that have been cooked for a long time, and although the cholent is fully cooked, there remains an issue of cooking until the bones are soft. Great care must therefore be taken to ensure that the cholent, including the bones, is fully cooked, so that one does not inadvertently speed up the cooking process. See ibid., p. 200.

    Regarding liquids, there is a question in the Poskim if a liquid that has already been heated to Yad Soledes Bo may be heated further to boiling point. Some Poskim argue that since the liquid has reached Yad Soledes Bo it is considered cooked and a further rise in temperature is not prohibited. Although this halachah is disputed, one may be lenient in this matter (Ibid., p. 198).

14. (Back to text) This is the case even if the stove is covered with a blech, the pot was held, and there was intention to return it - the three conditions of Chazarah. See ch. 7.

15. (Back to text) Shabbos KeHalachah, p. 216. Even ladling out food from a pot of food that is partially cooked and removed from the fire is prohibited.

16. (Back to text) Alter Rebbe's Shulchan Aruch 318:24.