Lots of supermarkets and caterers advertise themselves as being “glatt kosher.” What exactly is “glatt”? Is it Yiddish for “super-kosher”? And how does one receive such a designation?


The word “glatt” actually means “smooth” in Yiddish, and refers to the lack of adhesions on the lungs of an animal.

To understand this, we need to define another word that has taken on a whole new meaning, treif.

In the vernacular, the word refers to anything unkosher. In truth, treif refers specifically to an animal that has died a violent death, as the verse states, “Do not eat meat from an animal torn (treifah) in the field.”1

More broadly defined, this also includes animals that have physical defects that halachah determines will limit their lives. Even if such animals would be properly slaughtered and salted, their meat would not be kosher.

One of the more common invalidating defects is a punctured lung. Every animal2 needs to be inspected by an expert bodek (examiner) to determine that its lungs don’t contain any holes or defects.

This is where the term “glatt” comes in.

Glatt Kosher

Besides for the obvious holes, there are often sirchot, scar tissue–like adhesions, that sometimes develop on the lungs. These are problematic, since they indicate that there either was a hole that did not heal properly,3 or that a hole is developing in the loose tissue.4

Most adhesions on the lungs render the animal treifah—not kosher.5 Some, however, describe techniques by which one can squeeze, palpate and test some adhesions to ascertain whether they are bona fide sirchot or merely rir (spittle-like discharge), which would render the animals kosher.6

Rabbi Yosef Caro (the Beit Yosef), author of the Code of Jewish Law, strongly disapproves of this test, and holds that all adhesions are considered treifah.7

On the other hand, Rabbi Moshe Isserles, in his glosses to the Code, while opining that one should be strict and not rely on these tests, notes that it was the practice among Ashkenazic Jewry to at times be lenient and rely on this test if done by an extremely G‑d-fearing and qualified tester.8

Sephardim, who generally follow the rulings of Rabbi Yosef Caro, don’t rely on these tests at all. For Ashkenazim, who generally follow the rulings of Rabbi Moshe Isserles, there are two standards of meat: (a) kosher, which relies on this test; and (b) glatt kosher, meat from animals whose lungs were found to be smooth (glatt) without any adhesions.

Glatt/Chalak Beit Yosef

While on the topic of glatt kosher, it should be noted that if you go to a kosher butcher, you may find another category of meat called glatt (or chalak, the Hebrew equivalent) Beit Yosef.

Glatt in the classical sense means that there were no adhesions whatsoever, but since it is very uncommon to find totally smooth lungs, the majority of meat sold nowadays as glatt relies on the process of peeling and testing mentioned by Rabbi Isserles, but only for very light and soft adhesions which come off easily.9 As mentioned, Sephardim don’t rely on this test at all.

This, however, is the case only for beef. When it comes to other animals, such as deer, calves (veal) and lamb, all agree that no type of sirchah may be removed. All such animals sold today as kosher would essentially be glatt kosher.10

At the same time, when it comes to finding sirchot, not all areas of the lung are equal. While all hold that there are certain areas of the lung where a sirchah will not render the animal non-kosher, there is a disagreement as to what exactly these areas are. In this aspect the Sephardic view (following the Beit Yosef) is more lenient, with more areas where a sirchah can exist without affecting the kosher status of the animal. Those same sirchot would make the entire animal treif for Ashkenazim (following the rulings of Rabbi Isserles). In other words, while Rabbi Caro is more strict on the type of sirchah, he is more lenient when it comes to where it can be found.

In practice, many Sephardim follow the stringencies of both Rabbi Moshe Isserles and Rabbi Yosef Caro, so that they (a) don’t rely on any of the tests of sirchot, and (b) also don’t rely on the leniencies of Rabbi Yosef Caro about the sirchot found in certain areas.

Based on this, one can find three different types of kosher meat on the market: 1) plain kosher meat; 2) glatt kosher; and 3) glatt or chalak Beit Yosef, which follows the rulings of the Sephardim.

The Colloquial Term “Glatt Kosher”

If your local bakery advertises itself as “glatt,” it’s seemingly making the absurd claim that its cupcakes and donuts have healthy lungs. However, in colloquial speech, the term “glatt kosher” has come to be used—albeit inaccurately—to refer to something that is unquestionably kosher without having to rely on various leniencies.

At the same time, the opposite is also true. Nowadays, when the term “kosher non-glatt” is used for meat, it many times relies on various other questionable leniencies that have nothing to do with the issue of sirchot discussed above. This is just one of the reasons why it is crucial, especially when it comes to meat, for the kosher consumer to buy only products that have a reliable kashrut certification.