A few pages back, we learned a general rule from a mishnah: When a forbidden food inadvertently mixes with a permitted one, the mixture is forbidden if it adds a positive taste. If it does not, it is permitted.
Rav Yehuda says that Shmuel says: This is the law.
Why, you might be asking, would Shumuel need to tell us this? Doesn’t the mishnah already do so? It does, but it’s not the only source to weigh in. A beraita on today’s daf suggest there is a dispute about the matter:
Both food that imparts flavor to the detriment and food that imparts flavor that enhances the mixture are forbidden. This is the statement of Rabbi Meir.
Rabbi Shimon says: If the flavor is enhanced, it is forbidden, but if it is made worse, the mixture permitted.
https://www.myjewishlearning.com/article/tannaim-amp-amoraim/
Rabbi Shimon agrees with the mishnah that the permissibility of the mixture depends on whether the forbidden food enhances the overall flavor or not. Rabbi Meir rules more strictly, prohibiting a mixture of forbidden and permitted foods regardless of the impact of the forbidden substance. Given that there is a tannaitic dispute about the matter, the law could have gone in either direction. So we rely on Shmuel, a first generation amora (rabbi of the Gemara), to tell us that the law does indeed follow Rabbi Shimon.
In explaining its legal principle, the mishnah brought an example: forbidden vinegar that fell into split beans. Vinegar does not improve the taste of beans, so such a mixture is permitted. Rabbi Yehuda reports that Shmuel has something to say about this as well:
Rav Yehuda says that Shmuel says: The sages taught only where it fell into hot split beans. But if it fell into cold split beans, and one heated them, it becomes like (a dish) that enhanced and ultimately detracted from it, and it is forbidden.
Shmuel, apparently a bit more of a vinegar and split beans connoisseur than the mishnah, understands that the mishnah’s example is imperfect, as the beans’ temperature determines the effect of the vinegar. He clarifies: vinegar added to hot beans does not impart a positive flavor, so if some forbidden vinegar spills into hot split beans, the mixture is permitted. However, if the beans were cold, the vinegar enhances the flavor and the mixture becomes forbidden. To make things perfectly clear, he further explains that when vinegar falls into cold beans and is subsequently heated, the addition of the vinegar turns from benefit to detriment and the mixed product becomes forbidden.
This discussion is the primary source for the legal principle notein ta’am lifgam (imparting a negative taste), which applies not only to conversations about mixtures involving foods used for idolatry, but also the inadvertent mixing of kosher and non-kosher products, dairy and meat, and chametz with foods that are kosher for Passover.
Generally speaking, Jewish law follows Rabbi Shimon: When a forbidden substance inadvertently falls into a permitted one, the mixture is not forbidden unless it enhances the taste. This principle, however, is seldom applied in a vacuum. Other rules, like those about the relative volume of the two substances, also impact the status of the mixture. We’ll take a deeper dive into all this when we get to the eighth chapter of Tractate Chullin a little less than a year from now, so stay tuned.
Read all of Avodah Zarah 67 on Sefaria.
This piece originally appeared in a My Jewish Learning Daf Yomi email newsletter sent on August 24, 2025. If you are interested in receiving the newsletter, sign up here.
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