Talmud - Hullin 97b חולין צ״ז ב׳

and the Sages said that there are cases where the mixture is permitted if there is sixty times as much permitted food as forbidden food. Therefore, in a case where the mixture is a type of food mixed with food not of its own type, so that there is a difference in taste between the two components, when there are Jews for whom the mixture is permitted, one relies on a Jew tasting the mixture. This is the halakha when teruma is cooked with non-sacred food. When the mixture is potentially forbidden, e.g., in the case of meat cooked with milk, one relies on a gentile cook to taste it.

And if the mixture is composed of a type of food mixed with food of its own type, where one cannot ascertain whether the forbidden component has imparted flavor; or if it is composed of a type of food mixed with food not of its own type when the mixture may be forbidden and it is a case where there is no gentile cook available to taste it, the mixture is permitted if there is sixty times as much permitted food as forbidden food.

§ The Gemara (96b) cited Shmuel’s opinion with regard to the thigh of an animal that was roasted or cooked with the sciatic nerve still inside. The Gemara relates the following incident: There were those animal thighs that were salted in the home of the Exilarch with the sciatic nerve still inside; Ravina ruled that they were forbidden, whereas Rav Aḥa bar Rav Ashi ruled that they were permitted. They came and asked Mar bar Rav Ashi to render a decision. He said to them: My father permitted the meat in such circumstances.

Rav Aḥa bar Rav said to Ravina: What is your reasoning in prohibiting the meat? Is it because of what Shmuel said: A salted food item is considered like a boiling hot food item, and a food item marinated in vinegar, brine, or the like is considered like a cooked food item? Perhaps based on this statement of Shmuel you consider the salted thighs as though they have been cooked with their sciatic nerves, in which case they are forbidden.

But didn’t Shmuel also say (96b): They taught that the thigh is entirely forbidden only when it was cooked with the sciatic nerve inside it. But if the sciatic nerve was roasted inside the thigh, one may peel away the meat and eat it until he reaches the sciatic nerve, and then he removes the nerve.

And if you would say: What is the meaning of the phrase: Like a boiling hot food item, that Shmuel said? It is like boiling hot food that was cooked rather than hot food that was roasted, and therefore if the thigh was salted with its sciatic nerve the entire thigh becomes forbidden. This is not a convincing claim, because from the fact that Shmuel said: A food item marinated in vinegar, brine, or the like is considered like a cooked food item, it may be understood by inference that when he said that salted food is like boiling hot food he was saying that it is like boiling hot food that is roasted. The Gemara concludes: This poses a difficulty to the opinion of Ravina.

§ The Gemara elaborates on the statement that if permitted and forbidden foods are cooked together and there is sixty times as much permitted food as forbidden food, the mixture is permitted. Rabbi Ḥanina says: When they assess whether or not there is sixty times as much permitted food, they assess the volume of the broth, the deposits [kifa], the pieces of permitted food cooked in the pot, and the pot itself. The Gemara explains this last point: There are those who say this means that one includes the volume of the material of the pot itself, and there are those who say it means that one includes the volume of that which the pot has absorbed from the permitted food. When meat cooks its volume decreases, and some of the meat that constitutes that discrepancy is absorbed into the sides of the pot.

The Gemara continues its discussion of nullification. Rabbi Abbahu says that Rabbi Yoḥanan says: With regard to all forbidden foods that are prohibited in the Torah, if they are cooked with permitted food and one cannot tell whether they have imparted flavor to the permitted food, we assess the mixture as though the forbidden food were onion or leek [kaflot]. If that amount of onions or leeks would impart flavor to the permitted food, one must assume that the mixture is forbidden.

Rabbi Abba said to Abaye: But let one assess the mixture as though the forbidden food were pepper or other spices, which are even more pungent, in which case they would not be nullified even if they were mixed with a thousand times as much permitted food. Abaye said to him: The Sages ascertained that with regard to forbidden foods, there is nothing that imparts more flavor to a mixture than onion and leek.

§ The Gemara continues to discuss the nullification of forbidden foods. Rav Naḥman says: A sciatic nerve that was cooked with kosher food is nullified if the mixture contains permitted food that is sixty times the nerve’s volume, and the sciatic nerve itself is not counted in that number, because it cannot nullify itself. If an udder, which is meat but also contains milk, is cooked with other meat, the milk is nullified if the meat is sixty times its volume, and the udder itself is counted with the rest of the meat. If the egg of a non-kosher bird is cooked with kosher food, it is nullified if the permitted food is sixty times its volume, and the egg itself is not counted in that number, as it cannot nullify itself.

Rabbi Yitzḥak, son of Rav Mesharshiyya, says: In the case of an udder cooked with meat, even if the meat is sixty times the volume of the milk, so that the meat is permitted, the udder itself is forbidden, because the meat imparts flavor to the milk contained within the udder, which then renders the udder forbidden. And if the udder subsequently falls into another pot, it also renders the contents of that pot forbidden unless they are sixty times the volume of the udder.

Rav Ashi said: When we were in the study hall of Rav Kahana, a dilemma was raised before us: When we assess whether the contents of the pot are sufficient to nullify the udder, do we assess whether the pot contains sixty times as much permitted food as the entire volume of the meat of the udder itself, or do we assess only that milk which came out from the udder, since the udder itself has been removed from the mixture?

The Gemara responds: It is obvious that we assess the entire volume of the meat of the udder itself, as if we were to attempt to assess only that which came out of it, how would we know how much came out? The Gemara objects: If that is so, then if the udder falls into another pot, it should not render the food in that second pot forbidden, because it has been assumed that all the milk in the udder has been released into the first pot.

The Gemara explains: Since Rav Yitzḥak, son of Rav Mesharshiyya, says that even if there is sixty times as much meat in the pot as there is milk in the udder, the udder itself is forbidden, clearly the Sages equated the udder with a piece of non-kosher meat. Consequently, the reason the udder renders the contents of the second pot forbidden is that the udder is intrinsically forbidden, not because of the milk that is released into the pot while it is being cooked.

§ The Gemara addresses Rav Naḥman’s statement that if the egg of a non-kosher bird is cooked with kosher food, it is nullified if the permitted food is sixty times its volume, and the egg itself is not counted in that number, as it cannot nullify itself. Rav Idi bar Avin said to Abaye: Is this to say that the forbidden egg imparts flavor to the food with which it is cooked? But isn’t it true that when people want to indicate that food is tasteless, they say: This is like mere egg-water? This indicates that an egg does not impart flavor.

Abaye said to him: Here we are dealing with

Traduction : The William Davidson digital edition of the Koren Noé Talmud, with commentary by Rabbi Adin Even-Israel Steinsaltz.

Chullin 97b explores the sixty-to-one ratio rule for forbidden mixtures and debates whether thighs salted with the sciatic nerve remain permitted.