Q. Some time ago I sent this question and I didn’t get an answer yet, I would like to know the answer.
Is artificial meat created by starting cells taken from live animals. They are put into a culture media where they start to proliferate and grow, independently from the animal, all nutrients are vegetarian. This process would be efficient enough to supply the global demand for meat, and it is the future. All this would happen without any genetic manipulation, i.e. without the need to interfere with the cells’ genetic sequences, only by using animal DNA and plant nutrients. Producing cultured meat for processed meat products, such as sausages, burgers and nuggets should be comparatively simple, an in-vitro steak is considerably more of a challenge.
Is this meat considered meat at all? Is it kosher? Is it a limb from a live animal? (ever min hachai). Can you eat it with milk? Does it need salting?

A. On August 2013 media reported that scientists extracted cells from a cow and, at an institute in the Netherlands, turned them into strips of muscle which they combined to make a hamburger. Although research is ongoing and recently an Israeli start-up company, (Super Meat) began a fund raising campaign to create lab-grown chicken, enlisting the helpful Halachic opinion of some Rabbis. At this point in time, the mass production of cultured meat is still unrealistic in the foreseeable future. Therefore the Halachic discussion is primarily academic, still firmly entrenched in the realm of theory, as it is not known what the final cell extraction process will entail, and what the necessary nutrients to feed the cells will be.
In principle a food that contains only a minuscule amount of a non-kosher ingredient can still be considered kosher if the non-kosher ingredient is nullified (usually) by at least a factor of 60 to 1. This would imply that the Petri dish patty would be considered kosher even if it was harvested from a non-kosher source, as the final patty has 20,000 muscle fibres grown from only a few stem cells. However, the above rule does not apply to a “davar hama’amid,” an ingredient that establishes the shape and consistency of the resulting produce. The essential ingredient can never be nullified, no matter how small it is. (See Shulchan Aruch Y. D. 87: 11).
Some contemporary Rabbis that have dealt with the issue compared it to gelatin extracted from animal sources, that some Poskim permit (SeeYabia Omer 8, Y. D. 11). One of the main reasons for permitting gelatin is that it constitutes “panim chadoshos.” During the process of producing gelatin, the original bones are completely destroyed by the various acids and other chemicals, and the inedible gelatinous results bear no resemblance, not even by taste nor form to the original, and is therefore considered a completely new item. However, most Poskim, including Rav Aharon Kotler zt”l, Rav Eliezer Silver zt”l, Rav Moshe Feinstein zt”l, and Rav Yosef Eliyahu Henkin zt”l, all unequivocally prohibited gelatin, unless it was derived from properly shechted kosher animals. Nowadays, although the Israeli Chief Rabbinate permits gelatin as kosher and has a distinct designation, “kosher l’ochlei gelatin,” no Mehadrin kashrus agency or Badatz in Eretz Yisroel, or mainstream certifying agency in America considers real gelatin kosher, unless it is produced from properly shechted kosher animals.
Horav Shlomo Miller’s Shlit”a opinion is that the cultured meat is not considered meat. However, since the Mishna (Bechoros 5b) and Shulachan Aruch (Y.D. 79: 2) rule that food extracted from the impure is regarded as impure, even if it is not meat it is still prohibited. Therefore the original stem cells would have to be extracted from a kosher slaughtered animal. When the above was done, and all the nutrients used were kosher, the produce would need no salting and may in principle be permitted even with milk. (see next question concerning ma’aris ayin).

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a.