Blood and Fat
Now that we know which species are kosher, we have to see which parts of kosher animals are prohibited for one reason or another. For the time being, we shall skip over the laws that are related to the death of the animal - shechita, neveila, and tereifa.
There are three prohibitions in this category - forbidden fats (cheilev), blood (dam), and "gid ha-nashe" (the sciatic nerve). These apply differently to different types of animals. Fish, for instance, have none of these prohibitions. Hence, fresh fish can be eaten whole with no particular preparations, other than considerations of taste. The prohibition on certain types of fats applies to domestic animals ("beheima" - sheep and cattle) but not to wild animals ("chaya"), such as deer. Blood applies to all land animals as well as fowl.
The Torah prohibits certain fats found in animals. "You may not eat all cheilev of the bull, the sheep, and the goat" (Vayikra 7,23).
There are two terms in Hebrew for fat - "cheilev" and "shuman." The terms are more halakhic than physiological - "cheilev" refers to those fats that are prohibited and "shuman" to those that are permitted.
The Ramban (Vayikra 3,9) gives the following definition for the words "cheilev" and "shuman."
The term "cheilev" in the holy tongue refers to fat that is separate and not together with the meat as one thing; for the fat which is mixed in with the meat and not separate from it is called "shuman".... But "cheilev" is separated with a surrounding membrane and can be peeled.
The exact halakhic definition of the prohibited cheilev is somewhat more complicated (see YD 64). Basically, all cheilev is either found on internal organs of the animal (spleen, stomach, liver), or in the hindquarters (from the eleventh rib and below).
The art of removing all prohibited cheilev is called "nikur." Because it involves recognizing exactly what to remove and what not, it obviously cannot be learned from books alone. An expert in nikur has learned the trade "on the job," based on the guidance of halakhic works and under the guidance of an expert.
For this reason, and because it is indeed a difficult task to do properly, there are many places where nikur cheilev is not practiced fully. The hindquarters of the animal are simply sold to non-Jews. There is still need to do nikur for organs, such as the liver, but this is much simpler. This is the reason that it is nearly impossible to obtain meat from the hindquarters of an animal in the United States, for instance. The result is that, practically speaking, sirloin steak, for example, is not kosher - or, to be more accurate, is unavailable in a kosher form.
(Nikur is performed on liver. The heart also requires nikur to make it kosher. Most Ashkenazi communities today do not perform nikur on the heart and do not eat it.)
In fact, even when nikur was common, many people would not eat meat that depended on nikur, because of the difficulty involved. The Maharshal, for instance, writes that "I myself have heard and seen that most menakrim... will sometimes (not totally remove) the cheilev due to haste; and therefore I have accustomed myself to not eat meat that has undergone nikur unless it has been shown to another menaker who will check that it has been done properly."
In Israel, where an arrangement whereby half of every animal is sold to non-Jews is not practical, nikur is practiced. A "hechsher" on hindquarter meat in Israel requires not only supervision on the slaughter, but a far more demanding and rigorous supervision of the nikur.
The Torah forbids the consumption of blood (Vayikra 7, 26; there are four different places where this prohibition is repeated). There are two different reasons offered by the commentators for this prohibition, both of which are suggested by the verses in the Torah.
a. "But you must strengthen yourselves and not eat the blood, for the blood is the soul, and you must not eat the soul with the meat" (Devarim 12,23). The blood represents the life of the animal. Although the Torah permits the consumption of meat, it reminds us that a life - even an animal life - must be taken to do so, and it is important to restrain oneself somewhat from an act of such blatant devouring of life.
The Kabbalists, beginning with the Ramban, see in the devouring of animal blood a mixing of human spirit with that of the animal. Meat is common to man and the animals, and so the meat eaten becomes part of man, but the blood, the "soul and spirit" of the animal, does not lose its animalistic character.
b. "For the soul of the flesh is in the blood, and I have given it for you on the altar to atone for your souls, for blood atones for the soul; therefore I have said to the Israelites: no soul of yours shall eat blood" (17,10-11).
The blood of an animal sacrifice is spilled on the altar as a sign of atonement and therefore it is not appropriate for man to eat. (The same reasoning applies to the cheilev, which is also burnt on the altar). In fact, as this verse indicates, the two reasons are intertwined. Because blood represents the life and soul of a living being, therefore it is the vehicle of atonement for living man, and therefore it may not be eaten.
The blood that is prohibited is the "blood of life." This includes the blood that is spilled during shechita, and the blood found in the heart and major blood vessels. "Dam eivarim," the blood of the organs, is only prohibited if it has moved about from its original place. In order to remove this blood, which would become prohibited during cooking, we must "kasher" meat, either by salting or grilling. We will discuss "kashering" in a later shiur.
Part of nikur (even where nikur of the fats is not performed) involves removing major blood vessels and opening others so that the "blood of life" be taken out.
Not all blood is prohibited. For instance, we have already mentioned that fish blood is permitted. The Talmud (Keritut 19b) states:
The Rabbis taught: "You shall not eat all blood" (Vayikra 7). Do I infer that even the blood of humans, the blood in eggs, the blood of locust, and the blood of fish are all included (in the prohibition)? It is written: "in fish and animal".... I exclude the blood in eggs which are not flesh. The blood of locust and the blood of fish are permitted.
From this source, it would appear that blood found in an egg is permitted without any reservations. However, this is contradicted by another source.
Eggs... if a spot of blood is found on it, one should throw away the blood and eat the rest.
R. Yirmiya said: This is only if the blood is found on the "kesher."
[Rashi: kesher - this is the seed of the rooster that is attached to the top of the egg and from there the chick will begin to develop.]
Dostai the father of R. Aptoriki taught: This is only if it is found on the white, but if it is found on the yolk, the entire egg is prohibited. What is the reason? The corruption has spread throughout all of it. (Chullin 64b)
Tosafot (Chulin 64b) suggests two ways to reconcile these two sources. His first answer is that the gemara in Keritut is speaking of Biblical-level prohibitions (and hence is closely tied to the Biblical verses), whereas there is a rabbinic prohibition on the blood in an egg based on its similarity to the blood of the bird. This rabbinic prohibition is based on the fact that the chick will - in the future - develop from this point in the egg; hence, even though at the present the egg is defined as "not flesh," the rabbis prohibited this blood since this point could develop to be "flesh." If the blood has spread out into the yolk, this constitutes a later stage of development of the chick, and therefore - again rabbinically - the entire egg is prohibited.
A second answer in Tosafot claims that blood on the "kesher" is considered to be blood "of flesh" and is therefore prohibited Biblically, whereas bloodspots in the egg that are not, apparently, connected to fetal development are permitted.
a. The Halakhic Ruling
The Shulchan Arukh (YD 66,2) rules accordingly that a bloodspot in an egg is itself prohibited rabbinically and must be discarded. If the spot is found in a place where it appears to be part of the future development of a chick, it is prohibited Biblically. Furthermore, if blood is found in the yolk, the entire egg is prohibited.
The Rama, after first quoting several opinions how to determine exactly when the entire egg is prohibited, concludes that this uncertainty has given rise to the accepted custom "in these lands" (i.e., Germany and Poland) to prohibit any egg in which a bloodspot is found in any part of it, even if it is completely in the white (where it should be permitted according to all possible explanations of the Gemara in Chullin).
[Interestingly, the Pri Chadash (who was a Sefardi Rabbi) not only supports the Rama, but claims that it is not merely a custom to extend the prohibition, but rather a genuine prohibition. This is based on his claim that the chick develops from the white and not from the yolk.]
The result of this ruling is that it is customary to break eggs open one at a time in a glass in order to examine each one individually before mixing them together or adding them to a batter. If a bloodspot is found, the egg is discarded. (According to the Shulchan Arukh, this would depend on whether the spot was on the white or the yolk).
What if this examination has not taken place and the dish has already been cooked? In such a case, we rely on the principle of "rov." In cases of doubt, a statistical majority ("rov") may be relied upon. Since the majority of eggs do not have bloodspots, we may assume that there was none present. This principle of "rov" applies only where an examination cannot take place, since positive empirical knowledge is clearly superior to statistical conclusions.
The same reasoning applies to hard-boiled eggs. It is permitted to boil eggs in the shell and rely on the rov, since it is not possible to check it without breaking it.
b. Unfertilized Eggs
All this only applies to open-range eggs, where the possibility of fertilization exists. As we have seen, the only reason that blood in an egg could lead to the prohibition of the entire egg is because it is somehow related to a developing chick. Most eggs sold today are "factory-made;" the hens are kept in closed coops without any roosters. Such an egg cannot possibly develop a chick. The Talmud states:
Eggs which are "muzarot" [Rashi - where there was no male, and a chick will never develop in it], a normal person may eat them. (Chullin 64b).
The logic here seems clear. As we saw above, blood in an egg is permitted because it is not considered the blood "of flesh." The only reason there exists a prohibition is because of a presumed connection with a developing chick, and hence a relationship of sort with "flesh." But in an unfertilized egg, there is no possibility, in the present or in the future, of a developing chick. Hence, the egg is permitted.
The Shulchan Arukh adds, "but he must discard the blood" (66,7). Based on the sources we read above, there would appear to be no reason to discard the blood spot itself. Apparently, this is not the rabbinic prohibition based on the future developing chick mentioned by Tosafot, but a different one, based on the physical similarity between this blood and chicken blood. A similar prohibition exists on human blood once it has been separated from the body (for instance, if when biting into an apple, you find a spot of blood from your mouth on the apple).
In practice, the overwhelming majority of eggs sold to consumers today in Western countries are produced under "closed-coop" conditions. There are, however, a minority of eggs that may have come from breeding farms, which are basically in the business of growing chicks, but where surplus eggs are diverted and brought to market. The halakhic question is whether one can rely on the majority (another "rov") to permit an egg whose origin is not positively known (with only the spot itself being thrown away). Rav Moshe Feinstein (YD 1,36) was inclined to require examination of eggs wherever possible even under modern conditions, and to discard the egg if a bloodspot is found. If the egg has been mixed with others, many poskim would rule leniently under these conditions.
The reasoning of Rav Feinstein is based on an extension of the principle we mentioned above. Rov should only be relied on if a better method of determination does not exist. That is why regular fertilized eggs should be examined, even though there exists a rov there that there is no blood. Rav Moshe Feinstein argued that since most people do not consider the loss of a single egg to be a significant monetary loss, discarding the egg is preferable to relying on rov. Once more than one egg might be lost, we revert to the majority rule of rov.
4. Gid Ha-nashe
The first prohibition given to the Jews in the Torah is "gid ha-nashe," the sciatic nerve, found in the leg of an animal. This is mentioned in Bereishit 32,33. (If you are not familiar with the story, look it up.)
The Chinukh (3) describes the significance of this mitzva (based on the story in Bereishit) as:
To remind the Jews that even though they will suffer many troubles in the exile, at the hands of the nations and the hands of the children of Eisav, they should be confident that they will not be lost. Their children and their name will endure forever, and the redeemer will come for them and redeem them from oppression. And when they remember this idea through this commandment, they will be steadfast in their faith and their righteousness forever. This reminder is because that angel who wrestled with Yaacov was, according to our tradition, the guardian angel of Eisav, and he wished to destroy Yaacov from this world, he and his seed, but he could not do so. But he wounded him by touching his calf. So too, the children of Eisav will wound the children of Yaacov but in the end they will be saved from them, as we see that the sun shone (on Yaacov) to heal him and he was saved from the wound. So will the sun of the messiah shine on us.
The gid ha-nashe is found in the hindquarter and must be removed if that part of the animal is to be eaten.
This concludes our discussion of the kosher parts of kosher animals. Next shiur we will touch on some of the aspects of shechita, especially understanding what is "glatt kosher."