The Cholent Pot and the Water Urn on Shabbos: Got Them Covered?
The Cholent Pot and the Water Urn on Shabbos: Got Them Covered?
The melachah (the prohibition) of bishul (cooking) on Shabbos includes any act that aids the cooking process. Therefore, a pot sitting on the blech (metal sheet used on Shabbos to cover the flame or other heat source) containing food that is not fully cooked may not be covered or re-covered on Shabbos. (See Halachah #334 for how raw or partially cooked food may be set up for Shabbos with a blech or an alternative.)
Even if the food in the pot is fully cooked, it may still be an issue on Shabbos to cover it while it is on the fire (or plugged in); some poskim compare covering the pot to the issur (restriction) of hagasah (stirring), which is considered a part—or the culmination—of the cooking process.* Therefore, if the pot has been removed from the blech and uncovered, the lid should be replaced while the pot is still off the fire, before returning it to the blech (which must be done with certain provisions; see Halachah #414).
Moisture may accumulate on the inside of the pot lid during cooking. If it remains off the fire for more than a quick peek or stir, the steam droplets will cool. When replacing the covered pot on the fire, the cooled-off droplets will reheat, which may constitute re-cooking them, so some are stringent to wipe the lid dry before replacing it on a pot that is being put back on the blech.
An additional issur is hatmanah (wrapping): It is prohibited to wrap hot food on Shabbos for additional heat, or even just to insulate it (perhaps with a towel or blanket).
It is also an issur on erev (prior to) Shabbos to wrap food inside a heat source. In pre-modern times this entailed insulating with flammable materials such as coals; today it may be the heating element of an electric device. Covering a pot with its regular lid as a way of protecting the food within is not considered hatmanah. However, adding insulation to an ordinary pot on the fire, a crock-pot, hot plate or hot water urn (or other appliance used to warm food that has a flame or electric coils) by encasing the entire top or most of the sides with a towel or an appliance cover is problematic even on erev Shabbos. If the extra padding covers half (or less) of the pot’s body (by either falling short on the sides or exposing one side) and a small area on top of the pot remains exposed, it’s permissible. There are certain fabric Shabbos covers sold by Jewish companies made for this purpose, though the consumer should only purchase one for Shabbos use that is constructed specifically in a manner that avoids the halachic issue of hatmanah.
*Serving food straight from the blech or electrically connected pot is similarly restricted, since by inserting the serving spoon, the food is considered as if stirred.
(See Halachah #478 for Shabbos use of crock pots: how to create a blech and also deal with hatmanah issues.)
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