Lab-Grown Meat: Part 2

Is Cultured Meat Kosher?

In part one of this series, we broadly discussed the technology and process of growing meat in a lab. As a reminder, lab-grown meat is created from stem cells that are fed in a laboratory with specialized culture media. As the cells grow, they are induced to become muscle fibers. The tissue then matures to achieve the desired flavor and texture. We also raised questions about the kosher status of lab-grown meat. This installment will address the first few questions, one at a time.

1. Non-kosher stem cells: If the stem cells originate from a non-kosher animal, does this preclude the resulting meat from being considered kosher?
2. Kosher stem cells: Can the stem cells be harvested from a living kosher animal, or is this a form of eiver min hachai?
3. Salting: Must the animal have undergone melicha (salting to remove the blood), before the stem cells are procured?

The first concern we will address is nonkosher stem cells.
If the stem cells originate from a non-kosher animal, can the resulting meat be considered kosher?

The answer seems to be an obvious no. There is a clear ruling in Mishna Bechoros 5B: “That which is yotzei (comes out) from an impure animal is likewise impure.” This ruling would include stem cells extracted from a non-kosher animal. Since they are “yotzei min hatamei” they are considered not kosher and the subsequently engineered meat is not kosher.

However, there are two counterarguments.
1. Halacha only prohibits forbidden “food” items. Substances that do not qualify as “food,” such as dried out bones and hides, are always considered kosher, even when coming from a non-kosher animal. Halacha characterizes them as “mere dirt” (afra b’alma) or “mere wood” (eitz b’alma). They are NOT meat, and they are therefore kosher and pareve.

Theoretically, if the starter cells are procured from these non-edible parts of the animal, they could be considered halachically permissible and the subsequently engineered meat is kosher, too. While this technology is not yet available, it could become a consideration in the future.

2. Even if the starter cells are derived from a forbidden part of the animal, such as muscle tissue, or blood, an argument can still be made that the engineered meat could be kosher. This is based on the ruling of “zeh v’zeh gorem“; whenever there are multiple factors to consider, if one of these factors is forbidden and the other is permitted, the resulting product is often permitted. An example is presented in the Gemara (Avodah Zara 49a). Produce from a field that was fertilized with manure previously used for Avodah Zara, or a cow fattened by consuming beans offered as a sacrifice to an idol, are still permitted. The manure is not the sole cause of the resultant produce, nor is the grain fed to a cow the sole cause of its weight gain. In both cases, there is an additional, entirely permissible, cause. Therefore, the resulting product is permitted.

Lab-grown meat can be produced by a forbidden substance, a non-kosher stem cell. But there is a second element that is necessary for the starter cells to grow and multiply, namely the nutrients introduced into the petri dish that make cell division possible. Therefore, it follows that the cultured meat is the product of zeh v’zeh gorem and might be permissible if the nutrients are derived from kosher sources (even when the original cells are not).

On the other hand, it can be argued that the starter cells are the significantly more critical component, while the nutrients are far less important. Based on this argument, if the starter cells are not kosher, then the resulting meat is also not kosher as this is not an equal or typical zeh  v’zeh gorem.

These questions remain heavily disputed amongst poskim today and it is not within the scope of this article to fully adjudicate the arguments on both sides. I am just presenting some of the basic ideas relevant to this question.

Let’s move on to the next question.

Can the stem cells be harvested from a living kosher animal, or is this a form of eiver min hachai?
We can assume that we are procuring the cells from the muscle tissue of a kosher animal (and putting aside the argument of zeh v’zeh gorem). If the cells are extracted from the animal while it is alive, they might be considered forbidden as eiver min hachai and then the subsequent meat
that is engineered from these cells is likewise forbidden.

The consensus amongst the poskim is that this would be a problem, so the stem cells can only be extracted from the animal after it has been shechted in accordance with Halacha.

The same would be true regarding extracting the cells from a kosher animal that was killed without undergoing Halachic shechita. Such an animal is a neveila and its meat is not kosher, therefore the stem cells and resulting meat would be not kosher.

It seems that the only kosher way to have lab-grown meat is to extract the cells from a kosher animal that was shechted according to Halacha and whose meat is therefore permissible.

This does complicate things a bit. For the best results, stem cells should be extracted from the animal while it is still alive. Taking them from dead muscle tissue is certainly not conducive to cell proliferation.

Two solutions have been suggested.

1. Extract the stem cells immediately following shechita. This way the animal is shechted, but the cells are still alive. This suggestion is still subject to a question that we will deal with later – whether the meat needs to be salted before the cells are extracted.
2. Use of a ben peku’a. A ben peku’a is a live calf that was removed from a pregnant cow after it was shechted. Halachically this animal does not require shechita and the prohibition of ever min hachai does not apply.¹ One would be allowed to extract the cells from a ben peku’a while it is alive.

   It should be noted, however, that this solution is not so simple. There is still a Rabbinic obligation to shecht a ben peku’a (for reasons of ma’aras ayin). There are ways to overcome the issue of ma’aras ayin, but they are beyond the scope of this article.

Must the animal have undergone melicha (salting to remove the blood) before the stem cells are procured? Can stem cells be derived from animal blood, given that blood is not considered kosher for consumption?
The answer to this question is simple. The meat would not require melicha before extracting the cells. The Shulchan Oruch rules that one is allowed to chew a raw piece of meat even before it is salted because the blood inside only becomes prohibited after it is separated from the muscle
(typically by cooking). If the blood remains in the muscle, it is permitted.

Another way of looking at it is to understand that even before a piece of meat is salted the piece of meat itself is not prohibited. It is only the blood within that cannot be consumed. Therefore, when the cells are extracted from the muscle tissue, even if there is blood in the same piece, the extracted cells are permissible.

In part three, we will discuss nutrients fed to the cells in the lab to make them proliferate, the status of labgrown meat (whether it is considered pareve or fleishig), and how to deal with issues of ma’aras ayin.

These questions and more will be explored in this multipart series featured in the next few editions of Kosher Spirit.

1 Yoreh Deah, Siman 13, Taz 3.