Ancient sources do not provide consistent rationales for the dietary laws. Commentators suggest a variety of possible reasons.
Biblical association with "holiness"--Means of separating Israel from pagan world, minimizing social interaction and possibilities of intermarriage.
Form of moral self-discipline.
Hygienic and health-related reasons.
Moral symbolism (e.g., avoidance of wild beasts and fowl).*
Rejection of pagan rituals.
Definition of permissible species
Species defined in the Torah (see Leviticus 11; Deuteronomy 14)
"Beasts of the earth" (quadrupeds) "you may eat any animal that
has cloven hooves and chews its cud" (Leviticus 11:3;
Deuteronomy 14:6. Permitted animals must have these two features: Includes: sheep,
cattle, goats and deer are kosher.
"Of the things that
are in the waters, you may eat anything that has
fins and scales" (Leviticus 11:9; Deuteronomy 14:9). Excludes:
Birds: The Torah lists forbidden
birds (Leviticus 11:13-19; Deuteronomy 14:11-18), but does
not specify why these particular birds are
forbidden. All of the birds on the list are birds
of prey or scavengers. Theoretically, any bird not on the forbidden list should be permitted.However, since we are no longer sure about the identifications of the biblical names, it is generally required that permission be supported by a local tradition. Includes: chicken, geese, ducks and (acording to most authorities) turkey.
"Winged swarming things" (winged insects). Locusts and grasshoppers are permitted if they fit the definition in(Leviticus 11:22; hosever, most Jewish communities no longer eat them.
Additional Factors in the Preparation of Meat (including Fowl)
Ritual Slaughter [Shehitah]
Permitted mammals and birds must be slaughtered in
accordance with Jewish law.
the person who
performs the slaughter is called a shohet.
The method of slaughter is a
quick, deep stroke across the throat with a
perfectly sharp blade with no nicks or
unevenness. This method is painless, causes
unconsciousness within two seconds, and is claimed to be the most humane cost-effective method of slaughter
The shohet is not
simply a butcher; he must be a pious man,
well-trained in Jewish law, particularly as it
relates to kashrut.
not eat animals that died of natural causes
(Deut. 14:21) or that were killed by other
animals. In addition, the animal must have no
disease or flaws in the organs at the time of
slaughter. These restrictions do not apply to
fish; only to the flocks and herds (Num. 11:22).
Inspection of Animal's Health
Meat is forbidden if the animal:
was diseased and died (or would soon have died) of natural causes: nevelah Inspection of certain organs is carried out after slaughter to ascertain the health of the animal.
was killed in a manner other than shehitah; e.g, by a wild beast: terefah
Removal of blood
The Torah (Leviticus 7:26-27) prohibits the consumption of blood. Therefore the blood is allowed to drain after slaughter. An advantage
of shehitah is that it ensures rapid, complete
draining of the blood.
Afterwards, the remaining blood is removed by means of absorbtion through coarse salt, or by broiling
Removal of the Sciatic Nerve
The sciatic nerve is removed from meat, based on the biblical story of Jacob's struggle at Jabok, where he was injured in the thigh (Genesis 32:22): "Therefore to this day the Israelites do not eat the thigh muscle that is on the hip socket, because he struck Jacob on the hip socket at the thigh muscle."
Separation of Milk and Meat
Based on threefold repetition of "thou shalt not boil a
kid in its mother's milk." (Exodus 23:19; 34:26; Deut. 14:21), the oral tradition prohibits eating meat and dairy together. (The rabbis extended this prohibition to include not eating milk and poultry together.)
The separation extends to utensils, pots and pans in which meat and dairy foods are
cooked, plates and flatware from which they
are eaten, the dishwashers or dishpans in which
they are cleaned.
A traditional Jewish household will have at least
two sets of pots, pans and dishes: one for meat
and one for dairy.
One must wait between eating meat and dairy. Opinions and local customs vary from one to six hours.
Fish and eggs are not considered meat for this purpose, though the Talmud forbids eating meat and fish together for supposed health reasons.
Under appropriate circumstances, it is possible to cleanse utensils (by soaking, boiling, burning, etc.) so that they may changed over from dairy to meat use or vice versa.
According to biblical or rabbinic law, several portions must be set aside from the foodstuffs for the sake of the priests, Levites or poor. The food is forbidden until this is done.
Most of these rules only apply in the Land of Israel, and some can only be performed while the laws of purity are in force. Hence, the observance of these laws in usually of a symbolic nature.
Some Modern Developments in Jewish Dietary Laws
General rejection of dietary laws by classic Reform movement. Subsequently, the atttitude has been more favourable.
Tendency among traditionalists to discourage hygienic or historical rationales, because they imply the laws might no longer be applicable under changed conditions.
Tendency to stress ethical reasons for laws: e.g., Conservative Judaism forbids veal because of the inhumane treatment of animals.
While traditional dietary laws presuppose that most food preparation took place in the home (including slaughter, etc.), food production is now done on an indistrial basis.
Jewish communities and organizations issue certifications of "kosher" status. The consumer is required to check the labels of the retail products.