"Nat bar Nat" - The Status of Pareve Food Cooked in Dairy or Meat Pots

  • Rav David Brofsky



Last week we examined how the quality of the ta'am of a prohibited substance affects its impact upon a permitted mixture.  We noted that if the ta'am of a prohibited substance doesn't enhance the mixture but rather is detrimental to it (note in taam lifgam), the mixture is permitted even in the absence of sixty parts of heter.  Similarly, if the ta'am emitted from a non-kosher utensil is lifgam, which usually occurs after twenty-four hours of the utensil's exposure to the issur, then the food cooked in the utensil is permitted.


This week, I would like to discuss not the QUALITY of the ta'am, but rather its STRENGTH.  Does the halakha differentiate between ta'am which is strong and ta'am which is weak? Does the halakha distinguish between "primary" and "secondary" ta'am?


1.  "Nat Bar Nat" – The Source


The Gemara (Chullin 111b) states: "Fish which were 'brought up' ("alu") in a [meat] pot may be eaten with "kutach" (a dairy drink)..."


According to Shmuel, these fish may be eaten with milk, since the taste of meat which they absorbed was not considered "ta'am" (primary taste), but rather "noten ta'am bar noten ta'am" (secondary taste).  In other words, since the food did not absorb the taste directly from the meat, but rather from the pot which had previously absorbed the taste of the meat, this taste is considered "secondary," and the food MAY be consumed with milk.  This principle is commonly referred to in halakha as "nat bar nat." ("Nat" = notein taam).


The Ran (Chullin 51a) explains that although generally, the ta'am of issur can transfer its prohibited status to food and utensils even when weakened, the taste of a PERMITTED substance is different.  Since the secondary taste of meat is so severely weakened, it cannot create, when combining with milk, a NEW issur. 


2.  Definition of "Alu" – What Is Considered "Nat Bar Nat?"


What does the term "brought up" ("alu") mean? In which cases may the fish be eaten with milk?


The Rishonim offer three explanations of this Gemara, leading to three distinctly different halakhic conclusions.


The Rivan, quoting his father-in-law Rashi, maintains that the Gemara is referring to a case in which the fish are merely served hot upon a meat plate.  If however, the fish were actually cooked in the meat pot, then it would certainly be prohibited to eat the fish with dairy products.  The Acharonim debate whether the leniency still applies if both the plate and the fish are hot, or whether that case is considered actual cooking.  In any case, this approach substantially minimizes the leniency offered by Shmuel.


Most Rishonim (Rabbeinu Tam, Rambam, Rashba etc.) adopt an approach which stands in total contradiction.  They assert that whether the fish were served, cooked, or even fried in a meat utensil, they may still be eaten with milk.


The Sefer Ha-Teruma offers a middle position.  He agrees that if the fish were served or cooked in a meat utensil that they may be eaten with milk.  If they were FRIED, however, in a meat pot, they may not.  The Sefer Ha-Teruma considers taste transferred directly to the fish as a primary taste.  Only when the taste must pass through the medium of water, i.e., bishul, is the taste considered to be "nat bar nat," a secondary ta'am.


The Mechaber (YD 95:1) rules in accordance with the majority opinion, and allows fish which came in any sort of contact with a meat pot to be eaten with milk.


The Position of the Rema – "Chezkat Chalavi" and "Dairy Equipment"


The Rema disagrees.  He cites the opinion of the Rivan and notes that the prevalent custom is to be stringent le-chat'chila.  In other words, according to the Rema, food which was cooked or fried in meat utensils should not be eaten with milk.  Only if it was merely served ("alu") hot on meat plates may it be eaten with milk.


However, the Rema adds that be-di'avad, we are lenient.  The Acharonim explain that he is referring to a scenario in which food cooked in a meat utensil was already mixed with milk, in which case the mixture may be consumed.  Therefore, if one prepares coffee in a meat pot, one should NOT add milk to that coffee.  If, however, one already added the milk, the coffee is permitted.  Similarly, if one prepares pasta in a meat pot, one should NOT add cheese to the noodles.  If, however, one already added cheese, the mixture is permitted.


4.  What is the scope of the Rema's stringency?


The Rema notes that food which is fried or cooked in dairy utensils may not be eaten WITH meat.  However, this food may be eaten after meat, even during the same meal.  Therefore, one may serve a cake baked in a dairy pan for dessert after a meat meal. 


Furthermore, the Rema writes that it may be served on meat dishes.  The Acharonim discuss this comment of the Rema in light of another passage. In the next se'if (95:3), the Rema states explicitly that if one pours a liquid cooked in a fleishig keli rishon directly onto a dairy dish, then both the dish and the liquid are prohibited.


This stringency is based upon two assumptions. Firstly, as we shall see, the Rema rules that if meat and dairy utensils come into contact with each other in a keli rishon, they are prohibited. Secondly, the Rema assumes that water POURED from a keli rishon (iruy) has a status similar to water IN a keli rishon, as we shall see in a future shiur. These Acharonim debate whether we act in accordance with this statement of the Rema. Some claim (see Shakh 95:5) that be-di'avad the utensils should be permitted. One should consult a halakhic authority regarding such a case.


In recent years, terms such as "chezkat chalavi," or "dairy equipment," have entered the vocabulary of the kosher consumer.  These terms derive from this position of the Rema.  Food which was cooked in "dairy equipment" is considered "be-chezkat chalavi" and should not be eaten with meat, but may be consumed afterwards.  Furthermore, if it is unintentionally mixed with meat, the mixture may be eaten.


Incidentally, some kashrut organizations, such as the OU, refrain from specifying that a product was cooked on dairy equipment, and simply label the food as "dairy."  They fear that the equipment may not be clean, and therefore the issue may not be the status of "nat bar nat (absorbed secondary taam)," but rather actual mixture of dairy residue in the pareve food. 


The Rema notes further that if the dairy utensil in which the food was cooked was "eino ben yomo" - i.e., more than twenty-four hours have passed since it was last used for milk - one may le-chat'chila consume the pareve food with milk.


The Acharonim debate whether one may intentionally prepare food in an "eino ben yomo" dairy pot to be served with meat.  The Vilna Gaon writes that this should be permitted.  Others rule that in cases of need, i.e., if one doesn't have enough meat pots, it is permitted to intentionally use an "eino ben yomo" dairy pot to prepare pareve food for a meat meal.  Others insist that while one may not INTENTIONALLY do so, if one did not realize that the pot was dairy, or if one did not cook the food with the intention to serve it with meat, one may subsequently eat this food with meat.  Therefore, according to this opinion, if one cooked pasta in a pot which was "eino ben yomo" from its last contact with milk, if one did not realize that the pot was dairy or if one did not intend to eat the pasta with meat, one may consume the pasta with meat.


Finally, we should note that if a sharp food (davar charif), such as an onion, was cooked in a dairy pot, it should not, even be-di'avad, be consumed with meat.  The rule of "nat bar nat" does not apply to "davar charif" as we mentioned last week, we will discuss the issue of "davar charif" in greater depth in a future shiur. 


Before concluding this section, I would like to address one more question.  May one intentionally create a situation of "nat bar nat"? In other words, is the scenario portrayed by the Gemara of "fish which were brought up," regardless of how one interprets it, a le-chat'chila or a be-di'avad situation?  According to the Mechaber, may one purposely cook pasta in a fleishig pot while intending to serve it with cheese? According to the Rema, may one serve hot fish on a fleishig serving tray with the intention of putting butter on it?


Many Rishonim (see Mordekhai and Issur Ve-Heter), and later the Shakh (95:3), claim that one may not intentionally cause a situation of "nat bar nat."  In fact, the Acharonim debate, according to this opinion, whether the food is permitted to one who intended to rely upon "nat bar nat."  While the Minchat Kohen prohibits the food, the Peri Chadash permits it. 


However, the Beit Yosef (YD 95) cites a number of Rishonim who permit this practice, and therefore rules that one may even intentionally rely upon "nat bar nat"!


The custom of Ashkenazic Jewry is not to intentionally rely upon "nat bar nat."  However, Rav Ovadia Yosef (Yabia Omer YD 9:3) defends the opinion of the Beit Yosef and rules accordingly. Many Sefaradim, therefore, do rely upon "nat bar nat le-chat'chila," and consequently find very little need for pareve utensils.  The only pareve utensil required in such a household would be a pareve knife, as we shall see in a future shiur. 


5.  Washing Meat and Dairy Dishes Together


The Rishonim expand the discussion of "nat bar nat" to another important question – may one wash meat and dairy pots together?


Before we proceed, we should describe the process of "hadachat kelim" (dish washing) that the Rishonim are referring to.  Their case is one in which, interestingly enough, clean "ben yomo" dishes are washed together in a large basin of hot water.  In other words, the meat or dairy residue has already been removed from the dishes.  Our only concern is the transfer of ta'am, previously absorbed in the pots, from one keli to another.  Regarding the water, the basin can either be a "keli rishon" which was heated over a fire, or a "keli sheni," which contains water which was heated in a different vessel over a fire.


The Ramban, followed by the Rashba and others, maintain that the dishes are permitted.  The ta'am emitted by the dishes is considered "nat bar nat" and therefore there is no fear of "basar be-chalav." 


The Sefer Ha-Teruma disagrees.  He claims that the ta'am emitted from both the dairy and meat dishes may meet in the water BEFORE being weakened, creating "basar be-chalav" which will transform the water, through the mechanism of "chanan," into issur, subsequently prohibiting the pots. 


The Mechaber (YD 95:3) rules in accordance with the opinion of the Ramban.  Therefore, meat and dairy utensils washed together in hot ("yad soledet bo") water, even in a keli rishon, are permitted.  If, the Mechaber notes, the dishes weren't clean, the food residue may be nullified if there are shishim of water against the food residue.  Furthermore, even if the water does not constitute "shishim" against the food residue, if one places ashes (an abrasive cleaning agent) into the water, the food residue is rendered "pagum" (unfit for consumption) and the utensils are permitted.  We will return to this last point in next week's shiur.


The Rema adopts the view of the Sefer Ha-Teruma and prohibits the utensils if they were washed together.  However, the Rema offers three exceptions.  If even one of the utensils was "eino ben yomo" from its last contact with meat or milk, or if the basin was considered a "keli sheni," or if the pots were washed one after the other, and not simultaneously, the pots are permitted. 


The Taz notes that while the Shulchan Arukh's case may seem rather foreign to us, there are many practical ramifications to this debate.  For example, what if while cooking vegetables in a dairy pot, one accidentally stirred the contents with a fleishig spoon? According to the Rema, if both utensils were "ben yomo," and the spoon isn't "batel be-shishim" in the water, the pot, the spoon, and the vegetables are all prohibited!


Next week, we will briefly summarize how the principles of  "natlap" and "nat bar nat" are applied to common household kitchen accidents.  Then, we will discuss whether one may use a dishwasher for both dairy and meat dishes.  According to many opinions, the discussion may revolve around the concepts we introduced this week.