Non-kosher birds are listed outright in the Torah, but the exact zoological references are disputed and some references refer to families of birds (24 are mentioned). The MishnahBavli Chullin 3:22–23 refers to four signs provided by the sages. First, a (predatory bird) is not kosher. Additionally, kosher birds possess three physical characteristics: an extra toe in the back (which does not join the other toes in supporting the leg), a (crop), and a (gizzard) with a peelable lumen. However, individual Jews are barred from merely applying these regulations alone; an established tradition () is necessary to allow birds to be consumed, even if it can be substantiated that they meet all four criteria. The only exception to this is the turkey. There was a time when certain authorities considered the signs sufficient, so Jews started eating this bird without a because it possesses all the signs () in Hebrew.
Non-kosher birds are listed outright in the Torah but the exact zoological references are disputed and some references refer to families of birds (24 are mentioned). The MishnahBavli Chullin 3:22–23 refers to four signs provided by the sages. First, a (predatory bird) is not kosher Additionally, kosher birds possess three physical characteristics: an extra toe in the back (which does not join the other toes in supporting the leg), a (crop), and a (gizzard) with a peelable lumen. However, individual Jews are barred from merely applying these regulations alone; an established tradition () is necessary to allow birds to be consumed, even if it can be substantiated that they meet all four criteria. The only exception to this is the turkey. There was a time when certain authorities considered the signs sufficient, so Jews started eating this bird without a because it possesses all the signs () in Hebrew.