Israel’s Chief Rabbi Rules That Cultivated Meat Could Be Kosher. Not Everyone Agrees

For years the nascent cultivated meat industry has bristled at critics who say that their product, grown with a nutrient broth in a stainless-steel vat, is not meat. But when Israel’s chief rabbi ruled that Aleph Farms’ thin cut steak—a credit-card-size slab of beef cultivated from bovine stem cells that sizzles, tastes, and smells exactly like its conventional twin—is not meat, it was cause for celebration.

On January 18, after consulting with Aleph Farms’ production and research teams in Rehovot, Israel, Chief Rabbi David Lau, Israel’s pre-eminent Jewish authority, declared that Aleph’s steak could be considered kosher—permissible to eat for those following Judaism’s specific dietary laws.

In fact, he wrote in a ruling translated by the Jerusalem Post, Aleph’s steak, which does not come from a slaughtered animal and does not have blood, should be considered pareve—a vegetable product that is neither milk nor meat.

While actual Kosher certification can only be done by a certifying institution, and only once commercial sales are permitted by regulatory authorities, it is an important step forward for a young industry that is trying to revolutionize how the world produces meat. It is the first time that a religious leader has officially ruled on whether or not cultivated meat is acceptable for dietary restrictions. “This a huge step forward, and a very important milestone if we want to provide food for the next generation,” says Didier Toubia, Co-Founder and CEO of Aleph Farms. Toubia himself keeps kosher, but that is not the reason why the ruling matters, he says. Aleph Farms will also seek Halal certification for Muslim communities, as well as a ruling on whether or not observant Hindus, who do not eat beef, could eat Aleph’s steaks. “This is a protein solution for the world, not just for San Francisco and New York. We really want to make sure that most of the population in the world would be able to enjoy the benefits of cultivated meat,” says Toubia.

Read more: Exclusive: We Tasted The World’s First Cultivated Steak, No Cows Required

As cultivated meat comes closer to market—Singapore is the only country that currently permits the sale of cultivated chicken, from San Francisco based startup GOOD Meat, but the U.S. is likely soon to follow now that the Food and Drug Administration has deemed that Upside Food’s cultivated chicken is “safe for human consumption”—the conversation has moved from whether or not it is possible to produce on a commercial scale, to whether or not people will actually eat it. While kosher beef sales make up just a fraction of the global beef market, the Israeli Chief Rabbi’s imprimatur offers a wholesome-seeming stamp of approval on a new innovation that might otherwise be seen as a frightening adulteration of food by science.

Like most cultivated meat companies, Aleph Farms uses a small sample of cells that have been collected painlessly from living livestock to start the cell lines that are the basis of all their products. Those cells are grown in a nutrient-rich broth in a medical-grade bioreactor until they can be harvested as cuts of real meat, a process that usually takes a couple of weeks. By producing meat this way, companies such as Aleph Farms hope to significantly reduce not only animal suffering, but the outsize impact of the livestock industry on global warming. According to the United Nations, animal agriculture contributes 14.5% of global greenhouse gas emissions.

Read more: The Cow That Could Feed the Planet

“There are huge advantages to synthetic meat,” says Rabbi Menachem Genack, the New York based CEO of the Orthodox Union, one of the world’s largest kosher certification authorities, using an alternative term for cultivated meat. But as much as he would like to see companies like Aleph Farms succeed, he says he can’t agree with Rabbi Lau—even though he is a personal friend. “With no disrespect for the Chief Rabbi, we have a different opinion. [Aleph’s steak] cannot be kosher.”

In Rabbi Genack’s reading of the kosher laws, meat must be considered in terms of its origins—in the case of cultivated meat, the source animal for the original cell line. If meat is harvested from a living animal, even a microscopic amount of cells, “it’s not kosher,” says Genack. The solution, he says, is to obtain genetic material from a freshly slaughtered animal. “Maybe that is a little bit of a challenge, but if it’s possible to do, then it would be kosher.” While theoretically possible, this would go against cultivated meat companies’ principal selling point: no animal slaughter.

Read More: How Israel Became the Global Center For Alternative Meat Tech

The diverging opinions from some of the world’s top authorities on Jewish dietary law come from differences in how they see cultivated meat. Because it is grown, not slaughtered, Rabbi Lau’s ruling does not consider it to be meat. But because cultivated meat has an animal origin, the rules for kosher slaughter apply here too, says Rabbi Genack. What they can both agree on is that cultivated meat, whether or not it is considered permissible under Jewish dietary law, should not be served with dairy products, lest it appear to contravene one of the most important kosher laws of all: the prohibition against cooking meat with milk. So that still means no cheeseburgers, even with plant-based cheese.

correction, Jan 31

The original version of this story mischaracterized the reasons why cultivated meat is subject to the kosher guidelines for meat in general. It is it animal origins, not just because it looks and tastes like meat.