Introduction
Bishul on Food
- The melacha of ‘bishul,’ cooking, as it pertains to food is defined as preparing food for consumption via a fire or its derivatives (ie items heated up by the fire but do not themselves generate heat)
- Methods of preparation: This includes cooking, roasting, frying and baking. Unless stated otherwise, when we use the term ‘bishul’ or ‘cooking’ going forward it covers all these methods of preparation (though there are some halachos where we will explicitly distinguish between these methods).
- Sources of heat: Gas or electric stoves, steam cookers, electric ovens, hot plates etc are all included under the definition of ‘fire’ in relation to this melacha. The poskim debate whether cooking in a microwave would be a Biblical or Rabbinic prohibition (aside from the prohibition of using electricity) given the lack of a regular heating element (SA 318:3, MB 1, 17, SSK 1:1, 4, fn 11).
Bishul on Materials
- The melacha of ‘bishul’ also applies in non-food related contexts, by using heat to soften and harden materials.
- For example, melting wax or pitch, or hardening fresh twigs by drying them by the oven or firing pottery in a kiln would be forbidden due to bishul.
- Similarly, one of the reasons why it is forbidden to dry wet clothes by a source of heat is bishul (when it can reach the temperature ‘yad soledes bo’ – to be defined below iyH; this is also forbidden under the melacha of ‘melaben’, laundering), as drying the garment by the heat causes the garment to harden (others explain it is bishul due to heating the absorbed water) (MB 318:1, SSK 1(**)).
- Our treatment of bishul will focus on bishula s it pertains to food
Principles of Bishul
Liquids
- By liquids, one transgresses the melacha of ‘bishul’ by heating them to the point known as Yad Soledes Bo (we will refer to it as ‘YSB’ for short), the temperature at which one’s hand would recoil when touching the liquid. It is alternatively defined as the temperature which would burn a baby’s stomach (SA 318:14, SSK 1:5)
- In practice, we assume that YSB is a temperature of at least 45 degrees Celsius (113 farenheit) (SSK 1:1, fn 3, 17, Dirshu 318:99).
Solids
- Solids: by raw solid foods, one transgresses the melacha of ‘bishul’ by cooking them to the point known as Ma’achal ben Drusay (‘MBD’ for short), defined as when it is one third cooked (in his haste, a bandit named Ben Drusay would eat his food when it was only minimally cooked) (SA 318:4, SSK 1:5).
Cooking Non-Fully Cooked Foods Further
- Even when a liquid has reached Yad Soledes Bo, or a solid Ma’achal ben Drusay (as defined above), it remains prohibited to cook it further if it is not yet fully cooked. Therefore one may not further heat a liquid which is already YSB if it has not yet reached boiling point, nor may one further cook a solid which has already been cooked to the point of MBD if it is not yet deemed fully cooked (SA 318:4, SSK 1:5, fn17).
Kelim – Stages Removed from the Fire
- There is a distinction as to whether actions are forbidden due to ‘bishul’ or not depending on which ‘kli’ they take place in (‘kli rishon’ is defined as the pot which was heated on the fire; ‘kli sheni’ – a utensil poured into from a kli rishon; or ‘kli shlishi’ – a utensil poured into from a kli sheni), ie how many stages removed from the fire the cooking takes place. We will explore this in more detail on the coming pages
Prohibition to Eat if one Transgressed
- If one did cook food in a prohibited manner on Shabbos, there is a Rabbinic penalty to forbid eating that food on Shabbos (the same applies to most other melachos on Shabbos). If one was unaware that the action was forbidden (known as ‘shogeg’) then one may eat the food immediately after Shabbos, as may other Jews. However, if one was aware the action was forbidden (‘mezid’), the one who cooked it may NEVER eat that food, though other Jews may do so after Shabbos (SA318:1, SSK Intro 1:34).
- Note that there are numerous details about when this penalty applies – for example, if the action was only forbidden on a Rabbinic level one may benefit from it on Shabbos if one transgressed it unknowingly, similarly if the permissibility of the action was subject to dispute the penalty may not apply. In extreme circumstances (eg in challenging family situations) there may be more room for leniency. Therefore, it is advisable to consult with a Rav to determine if the penalty indeed applies or whether after the fact one may benefit from the food (MB 318:2-3, 7, SSK Intro 1:34).
On the next page we will iyH explore the halachos of ‘bishul achar bishul’, re-cooking cooked foods, as well as ‘afiya achar bishul’, baking cooked foods etc
