Jewish Cheese

Jewish Cheese is cheese where the cheese-making process was done by a Jew and is thereby rendered as kosher. And Non-Jewish Cheese is cheese where the cheese-making was done by a non-Jew, with this prohibition being more severe than the prohibition on milk.

The laws of cheese are discussed in Yoreh Deah section 115.

The Prohibition

The prohibition of non-Jewish cheese is discussed in the Mishnah, where Rabbi Yishmael asked Rabbi Yehoshua: why is this forbidden? Initially, he told him that it's because they set it with the stomach of a neveilah (the contents of the stomach - liquids and curds - of an animal not slaughtered according to Jewish law, which have properties that cause cheese to set). When he asked - but even in a burnt offering which is forbidden for benefit, it's permitted to consume what's in the stomach, since it's merely a secretion? He answered: it's because they set it with the stomachs of calves used for idol worship. When he asked - if so, it should be forbidden to derive any benefit from it? He changed the subject.

The Gemara says that the reason he changed the subject was because it was a new decree, and they wouldn't reveal the reasons for new decrees until some time had passed (12 months) so that the decree would spread. The true reason is:

• Rabbi Shimon ben Pazi said in the name of Rabbi Yehoshua ben Levi: Because of piercing. That is, because of concern that a snake pierced it (and they aren't careful about exposed cheese unlike wine and water, since they strain it), and the venom isn't lost but remains in the holes.
• Rabbi Chanina said: (according to Rashi this is a different explanation:) It's because remnants of non-kosher milk remain in the holes of the cheese. (According to Tosafot, this is another explanation:) Or he came to explain Rabbi Yehoshua ben Levi's approach - that the venom remains in the holes and doesn't prevent the cheese from setting, so it's still forbidden.
• Shmuel said: It's because they set the cheese with the skin of a neveilah's stomach, and the skin is not a secretion (like its contents), and it makes it forbidden.
• Rabbi Ada bar Ahava: Because they smooth the cheese with pig fat. Rabbi Chisda: They set it with vinegar (of wine). Rabbi Nachman: They set it with sap from orlah fruits. The Gemara challenges the last two methods - shouldn't it be forbidden to derive benefit from it? And the question remains unresolved.

Rabbeinu Tam says that since the law follows Rabbi Yehoshua ben Levi, and since today we aren't concerned about exposure (because snakes aren't common among us), the decree is nullified. But the Ramban objected, saying: even though the reason is nullified, since it was forbidden by "a count" (formal vote), it cannot be permitted without "a count." The Tur didn't bring Rabbi Yehoshua ben Levi's reason, because we aren't concerned about exposure. Tosafot brought there: that even if the cheese was set with flowers and herbs and the like - it's permitted, and there's nothing to worry about. But the Rambam ruled in the name of the Geonim that the decree applies to all types of cheese.