Unlike mammals and fish, it is not mentioned in Tora any formal factors which woulld allow to distinct between kosher birds and non-kosher. Pentateuch only limits by specifying 24 species of birds which are prohibited for Jews to eat. (Vayikra, 11:13-19; Devarim, 14:12-18). What is more, over time Jews had forgotten what are these birds and as a result were forced to limit themselves with a small number of birds concerning which existed a stable kosher tradition.
Nevertheless, sages of Mishna (Chulin, 3:6) indicated a set of criteria which enable to state kosherness of the bird. In their opinion, feathered which are allowed to Jews in food must have the following characteristic 1) to have an extra toe (facing the opposite direction of the others), a crop, and a gizzard; 2) not to be predators. However, at the times of Talmud (Chulin, 62 b) happened an incident – when Jews revealed a new bird which had first three characteristics and recognized it as kosher – and only later accidentally found out that it is a predator and consequently is prohibited in food. Therefore, Rashi declared that kosher could be considered only these birds towards which exists a reliable tradition; chicken, duck, goose, pigeon… Many religious authorities joined that opinion, e.g. r. Mashe Isserles (Jore Dea, 82:3).
Due to the fact turkey is а native of New world and it was brought to Europe only in 1519, any tradition related to this bird, needless to say, did not exist. Nevertheless, Jews begun to eat turkey almost simultaneously with their neighbours-Christians. What is more – how it happened, nobody knows precisely: all questions on kosherness of turkey emerge in halakhic literature only post factum!
There exist two explanations in what way turkey got its kosher certificate. According to first expalnation, it is due to the fact that turkey meets all four criteria of kosher mentioned in Talmud. Another explanation is more curious: many rabbis incorrectly thought that turkey is from India (by the way, in modern hebrew «turkey» – tarnegol hodu, «Indian turkey»), and were sure that Indian Jews had tradition about its kosherness!
At the moment, kosherness of turkey is a widely recognized fact. However, it is necessary to notice that back in the day a number of rabbis, including a well known Yom-Tov Lippman Heller (Tosafot Yom-Tov, 1579-1654), regarded turkey as non-kosher, and his descendants still share this opinion. As one of them living in America said, as a result annually he faces with «November dilemma»: on the one hand – family tradition, but on the other – what is Thanksgiving Day without a turkey?
- Is it kosher? app
- Android – https://play.google.com/store/apps/details?id=com.kosherdev.koshergator
- iOS – https://itunes.apple.com/WebObjects/MZStore.woa/wa/viewSoftware?id=855252975&mt=8
- Amazon – http://www.amazon.com/KosherDev-Is-it-Kosher/dp/B00I8S43HW/
- Blackberry – https://appworld.blackberry.com/webstore/content/59962547
- WinPhone – https://www.microsoft.com/en-us/store/apps/is-it-kosher/9nblggh6cs0w