Can I warm up meatballs on Shabbat morning? I am Ashkenazi Rabbanit Debbie Zimmerman

Some basics about cooking on Shabbat

The laws of heating food on Shabbat are complex. While there is broad consensus on the larger issues, there are many nuances that are disputed. In this case we will go through the basics and progress to the disputed details.

On Shabbat cooking food is prohibited, but in many cases heating previously cooked food is permitted, due to the general halachic rule of “ein bishul achar bishul” – meaning once something is considered cooked it can’t be cooked again. Halachic authorities mention a few possible exceptions to this rule – the two that apply to this case are a davar lach (something wet) and mitztamek v’yafeh lo (something that improves the longer it’s cooked). To give a practical example of these exceptions: using a permissible heat source (such as a blech or hot plate) to heat a dry meat loaf on shabbat would not be considered cooking; but doing the same with meat balls in sauce might be.

Based on a gemara in Shabbat 34a, amongst other sources, several Rishonim maintain that the rule of “ein bishul achar bishul” does not apply to liquids.[i] Both the Shulchan Aruch and Rema agree that “yesh bishul achar bishul bidavar lach shenitzanen” – if a cooked davar lach has cooled, reheating it is considered cooking.[ii] Some halachic authorities disagree, and either allow reheating of precooked liquids no matter what (see Ritva Shabbat 39a), or do not allow for reheating liquids if they haven’t maintained their heat (see Rosh Shabbat 3:10) – still, most contemporary Ashkenazic authorities hold like the Rema.

In order to understand what we may heat on shabbat and how that can be done we must explain the definition of each part of this sentence:

The definition of davar lach:

While something like soup is clearly considered davar lach, other consistencies are disputed. Most foods will release condensation when reheated, so what amount of liquid in a dish constitutes a davar lach? While the most stringent opinions hold that any liquid at all is a problem, there are more lenient opinions.[iii] Some halachic authorities ruled that when the liquid is not the majority of the dish the food is considered a solid.[iv] Others rule that if the liquid/sauce is significant on its own it is a problem to heat the food on shabbat.[v] Most meatballs are problematic in both these regards. The Mishna Berura (318:32) rules that if one wants to heat food such as meatballs one must pour out the liquid from the dish.[vi]  This view was accepted by Rav Shlomo Zalman Aurebach (Maor Hashabbat Vol. 1 Letters 1, 2) and Rav Moshe Feinstein (Igrot Moshe 4:74) and it is a prevalent Ashkenazic opinion today.[vii]

What is considered bishul – heating/cooking:

Chazal (Shabbat 40b) defined cooking liquids as heating them until the point of “yad soledet bo” – a hand recoils from the heat. This gives quite a range – since yad soledet bo can be interpreted as so hot that the hand immediately recoils and can’t bear to touch the thing at all (which is estimated to be around 70°C), or hot enough that the hand can’t remain for more than a few seconds (which is closer to 45°C). These two explanations led many halachic authorities to use both minimum and maximum definitions of yad soledet bo. The minimum gives us the temperature at which a liquid is considered cooked when heated on shabbat, and the maximum determines how hot a liquid must be before shabbat so that it is considered cooked.[viii]

Now that accurate thermometers are readily available there is some debate among halachic authorities as to the exact temperature. Rav Shlomo Zalman Aurebach rules the low definition of yad soledet bo is 46°C, 114°F. (Kovetz Noam Vol. 7)

Therefore, if one heats a food to a temperature that does not yet reach the minimum of yad soledet bo – for our purposes 46°C – it would not be considered cooking. Based on a gemara that allows cold water to be placed adjacent to the fire to dispel the cold, the Shulchan Aruch rules that this is allowed as long as the food is not placed in a location it can reach yad soledet bo  – if it does it would be considered cooking. (OC 318:14) The Rema adds that some allow one to place cold liquids in a place that is adjacent to the fire that could reach yad soledet bo, as long as it is not on the heating surface itself, but he himself rules this is not allowed when the liquid has completely cooled – which is the case when something is taken out of the refrigerator. (ibid:15)

Some Ashkenazim rely on more lenient opinions concerning davar lach and mitztamek v’yafe lo in cases when the liquid is not an essential part of the dish – such as a bit of juices in the bottom of a roast chicken – and therefore even if it is heated to yad soledet bo it would not be considered cooking. Still, when the liquid is more central to the dish, such as in meatballs, one should take the more stringent approach and refrain from warming the dish in a place where it can reach yad soledet bo.