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Dietary Laws


DIETARY LAWS , the collective term for the Jewish laws and customs pertaining to the types of food permitted for consumption and their preparation. The Hebrew term is kashrut, which is derived from the root כשר ("fit" or "proper"). The word appears in the Bible only three times (Esth. 8:5; Eccles. 10:10; 11:6) and even then not in connection with food.

Description of Permitted Foods

Although there are laws which qualify the consumption of agricultural produce (see *Mixed Species; *Terumah; *Orlah; *Wine; *Idolatry), from the point of view of the dietary laws all fruit and vegetables are permitted. This is in fact the force of the first dietary directive in the Bible: "Behold I have given you every herb yielding seed which is upon the face of the earth and every tree …" (Gen. 1:29). Vegetables may also be consumed with either meat or milk (see below, Milk and Meat). The dietary laws therefore concern themselves with what animals, birds, and fish may be eaten, the way in which they must be prepared for consumption, and the fact that meat must not be consumed or cooked together with milk orother dairy products.


The Bible classifies those animals permitted for consumption as tahor ("clean"), and those prohibited as tame ("unclean"). The distinction is traced to the wording of Noah's instructions. "Of every clean beast thou shalt take to thee seven and seven, each with his mate; and of the beasts that are not clean, two (and two), each with his mate" (Gen. 7:2). The criterion seems to have been the animal's sacrificial suitability, rather than pagan taboos.

Animals that chew the cud and whose hooves are wholly cloven, are "clean" (Deut. 14:6). Ten such herbivorous animals, both wild and domestic, are specifically enumerated in the Pentateuch: the ox, the sheep, the goat, the hart, the gazelle, the roebuck, the wild goat, the pygarg, the antelope, and the mountain-sheep (Deut. 14:4–5). Animals that have only one of the required characteristics (like the camel, which does not have split hooves, or the pig, which does not chew the cud) are forbidden (Deut. 14:7–8). Altogether, the Bible enumerates 42 "unclean" animals (see Table: Clean and Unclean Animals).


Leviticus 11:13–19 lists 20 "unclean" birds, and Deuteronomy 14:12–18 enumerates 21. From these two lists, the rabbis compiled a total of 24 "unclean" birds (Ḥul. 63a–b). All birds of prey are forbidden, such as the vulture, the osprey, the kite, the falcon, the raven, and the hawk. The Bible does not list "clean" birds. According to the Mishnah (Ḥul. 3:6), "clean" birds must have a crop, a gizzard which can easily be peeled off, and an extra talon (see Table: Clean and Unclean Animals). Today, only those birds for which there is a tradition that they are "clean" are permitted (Ḥul. 63b). With regard to certain birds there is sometimes a difference of tradition; thus in some German communities, the pheasant was regarded as "clean" whereas in others it was forbidden. There are differences of opinion also with regard to the turkey (for a complete list and discussion see: Sinai, 64 (1969), 258–281). Since "anything which comes from the unclean is unclean" (Bek. 7a–b), the eggs of forbidden birds are also forbidden (Ḥul. 64b). The Talmud lists among the indications for such eggs the fact that they are round rather than oval, and that the yolk is often on the outside and the albumen on the inside (ibid. 64a). Even the eggs of permitted birds are forbidden if they have been fertilized (ibid. 64a–b). That is usually seen from the fact that there is a dark spot in certain parts of the albumen. However, since there are several opinions among the authorities as to where the "danger zone" is, any spot of blood in the egg renders it unfit for consumption unless it comes from a chicken run in which there is no cock (and cannot therefore have been fertilized); it may be eaten if the spot itself is removed.


Only aquatic creatures that have at least one fin and one easily removable scale (kaskeset) are "clean" and permitted (Lev. 11:9–12; see Table: Clean and Unclean Animals). The Committee of Laws and Standards of the Rabbinical Assembly of America (Conservative) has ruled that both the sturgeon and the swordfish are permitted, whereas in England the Ashkenazi authorities forbid sturgeon while the Sephardi permit it (see et, 7 (1956), 208).


Leviticus 11:21–22 specifically permits the eating of four kinds of *locusts. "But all other flying creeping things, which have four feet, shall be an abomination unto you" (11:23). However, since even the permitted locusts cannot be easily identified today, they are not eaten by most communities. Although the bee is a forbidden insect, its honey is regarded as "transferred nectar" and may therefore be eaten (Bek. 7b).

*Shehitah ("Ritual Slaughter")

Specific regulations govern the method by which an animal must be slaughtered before it is permitted. So complex and minute are the regulations that the slaughter must be carried out by a carefully trained and licensed shohet. It is his duty both to slaughter the animal, and to carry out an examination (bedikah). Should a defect be found in some of the organs, such as the brain, the windpipe, the esophagus, the heart, the lungs, or the intestines, the animal is terefah, and forbidden for consumption. Defects are normally classified under eight categories (Ḥul. 43a): nekuvah, perforated organ walls; pesukah, split pipes; netulah, missing limbs; haserah, missing or defective organs; keru'ah, torn walls or membrane covers or organs; derusah, a poisonous substance introduced into the body, when mauled by a wild animal; nefulah, shattering by a fall; shevurah, broken or fractured bones. It is assumed in the Talmud that any of these defects would lead to the death of the animal within one year (Ḥul. 3:1; see below). Only if the animal has none of these injuries, is it pronounced kasher. After shehitah, it is suspended head down, so that as much blood as possible may drain.

Should various sections of the animal have been removed before the bedikah has taken place, the animal is usually considered kasher. This rule is based on the fact that the majority of animals are usually found, after bedikah, to be kasher (Ḥul. 11a–b). This rule, however, does not apply if the lung has been removed. Since a large minority of animals do suffer from lung diseases that portion of the body must always be examined and if that is impossible the animal is considered terefah.

Shehitah and bedikah of poultry is carried out in the same careful manner. The same laws of terefah apply but there is no need for examination except of the intestines. There are no specific rules concerning the method by which permitted fish are to be killed.

Koshering ("Preparation of Meat")

The prohibition against the consumption of blood (Lev. 7:26–27; 17:10–14) is the basis for the process of koshering meat. The purpose of the process is to draw out and drain the meat of non-veinal blood, before it is cooked. The blood can be removed either by salting the meat, or by roasting it over an open flame.

The salting process is begun by fully immersing the meat and bones in clean, cold water (in a vessel used exclusively for this purpose), for 30 minutes. The purpose of this operation is to open the pores, and remove any blood on the surface, thus enabling the salt to draw the blood out of the softened fibers of the meat. The meat is then laid out on a special grooved orperforated board, which is slanted, in order to allow the blood to flow down. It is then sprinkled with salt. The salt should be of medium texture; neither fine (which melts away), nor coarse (which falls off). Poultry should be opened and must be salted inside and out. The meat is then left to stand, for one hour, after which it is washed two or three times in cold water. In an emergency, i.e., when the meat is intended for a sick person or when time is short on the eve of Sabbath, the periods of immersion and salting may be reduced to 15 and 30 minutes respectively.

The salting process cannot be used if more than 72 hours have elapsed since the time of the shehitah. Such meat can only be koshered by roasting over an open flame, a process which is considered to be more effective in removing the blood than salting. It is, however, customary to salt the meat a little, even if it is to be roasted over an open flame.

Before koshering, the vein which runs along the front groove of the neck must be removed or cut in several places. The heart, too, is cut in several places and the tip is cut off so that the blood may drain. The gizzard is cut open and cleaned before koshering. Salting is not considered effective enough to kosher the liver, which is full of blood. It is therefore sprinkled with salt, cut across or pierced several times, and placed on or under an open flame, until it changes color, or a crust forms.

Other Regulations Regarding Meat

forbidden portions of clean animals

It is forbidden to eat certain portions of "clean" animals. The sciatic nerve (nervus ischiadicus; Heb. גִּיד הַנָּשֶׁה), for instance, must be removed before any animal, other than a bird, can be prepared for consumption. The prohibition is traced back to the blow inflicted upon Jacob: "Therefore the children of Israel eat not the sinew of the thigh-vein which is upon the hollow of the thigh unto this day" (Gen. 32:33).

The fat portions (ḥelev), attached to the stomach and intestines of an animal, sacrificed on the altar in biblical and Temple times, are also forbidden for consumption. They must be removed by porging (nikkur) the organs to which they are attached. The abdominal fat of oxen, sheep, or goats, unless itis covered by flesh, is forbidden (Lev. 3:17; 7:23–25).

nevelah and terefah

It is forbidden to eat either a nevelah (an animal that dies a natural death, or that has been killed by any method other than shehitah; Deut. 14:21), or a terefah (an animal that has been torn by a wild beast; Ex. 22:30). The term terefah is also applied to an animal sufferingfrom an injury which may lead within a specific time to its death (see above). Such an animal is absolutely prohibited for consumption. The Talmud (Ḥul. Chap. 3) describes over 70 such injuries and lesions (see also Sh. Ar., yd 29–60; Maim., Yad, Shehitah 10:9), which Maimonides describes as "the limit" and which, he says "must not be increased even though it should be found by scientific investigation that other injuries are dangerous to the life of the animal" (Maim., Yad, ibid. 10:12), or diminished "even if it should appear by scientific investigation that some are not fatal; one must go only by what the sages have enumerated" (Maim., Yad, ibid. 10:13).

admixture of permitted and forbidden foods

It is forbidden to eat any amount (no matter how minute) of forbidden foods (Yoma 74a). In the case of an accidental mixture of a forbidden food with a permitted one, however, the latter is only considered to be "contaminated" if the quantity of forbidden food inserted is large enough to affect the taste. For practical purposes, it was decided that only if the quantity of forbidden food was less than 1/60 of the permitted food with which it became mixed, is it considered not to have affected the taste. If more, the whole mixture is forbidden. If the forbidden admixture is, however, a type which is intended to affect the taste, then the mixture is forbidden even if the admixture is less than 1/60. Any leaven which becomes mixed

Characteristics: Viviparous1, suckle their young, breathe though lungs, hairs on the skin; the body temperature is constant, four-chambered heart (two auricles and two ventricles); the chest cavity is separated from the ventral by a diaphragm.
Ruminants with cloven hooves a) Cloven-hoofed but non-ruminants
Characteristics: herbivorous, they have incisors in their upper jaws. Ruminants, the stomach has four compartments. They have either hollow or solid horns2. They are cloven-hoofed, with two toes. Examples: buffalo, kine, goat, sheep, ibex, gazelle, deer, antelope, wild ox, wild goat, giraffe(?)3.Characteristics: They walk on their hooves, possess canine and incisor teeth.
Examples: pig, boar, hippopotamus.
b) Ruminants but not cloven-hoofed
Characteristics: They have very small hooves, like nails, walk on cushion-like pads which form the soles of their feet. They have tusk-like canines on both jaws and incisor teeth on the upper jaw. Their stomach has only three compartments.
Examples: camel, llama.
c) Solid-hoofed
Characteristics: They are herbivorous, have a single stomach, incisor teeth on both upper and lower jaws.
Examples: horse, ass, mule, onager, zebra.
d) Carnivorous
Characteristics: They have six incisors and two sharp canine teeth on both jaws. They have four or five toes with claws on each foot and walk either on their toes or on their paws.
Examples: cat, lion, leopard, dog, wolf, jackal, fox, hyena, bear.
e) Other mammals neither ruminants nor cloven-hoofed
Examples: hare4, mouse5, hyrax6, bat7, rat, elephant, ape, whale.
1) Mammals exist in Australia and New Zealand belonging to the order Monotermata, which lay eggs.
2) In this group the females have no horns. In the majority of species the males shed their horns annually. Some primitive species of cloven-hoofed ruminants are entirely without horns. There is some doubt as to whether they are clean.
3) The giraffe is a cloven-hoofed ruminant with a kind of horn, but there is no clear tradition as to whether it is kosher. Some hold that it is the tahash mentioned in the Bible and some the zemer of Deut. 14:5. The okapi belongs to the same family as the giraffe and has the same characteristics.
4) The hare is enumerated in the Bible (Lev. 11:6; Deut. 14:7) among the ruminants which are not cloven-hoofed. In point of fact it is not actually a ruminant although it appears to be one. See*Hare.
5) The mouse (akhbar) and the rat (holed) are enumerated in the Bible (Lev. 11:29) among the "creeping things" which are forbidden for food and whose carcasses render unclean by contact. Six other "creeping things" which are not mammals but reptiles are mentioned in the same verse and context. See later.
6) The hyrax is listed (Lev. 11:5) with the non-cloven-hoofed ruminants. Systematically it does not belong to the ruminants but in its anatomical structure it is somewhat similar to them.
7) The bat is enumerated in the Bible (Lev. 11:19; Deut. 14:18) with birds, because it flies, but systematically it belongs to the mammals.
Characteristics: Their bodies are covered with feathers, and their upper limbs are wing-shaped. They have no teeth, breathe through lungs, and have a constant body temperature. The heart is four-chambered (two auricles and two ventricles). They lay eggs which have a hard shell of calcium carbonate (chalk).
The Bible does not give the characteristics which distinguish clean birds from unclean, as it does in the case of mammals and fish. The Mishnah, however (Ḥul. 3:6), states that "a bird that seizes food in its claws is unclean; one which has an extra talon1, a craw, and the skin of whose stomach can be peeled, is clean." To this the Talmud adds in the name of R. Nahman that "to anyone familiar with birds and theira) Diurnal Birds of Prey
The Diurnal Birds of Prey mentioned in the Bible are from the family Falconidae which are carnivorous and Vulturidae which feed on carrion. Falconidae: have hooked beaks and their talons are sharp and bent like hooks.
Examples: kestrel, hawk, eagle, kite, buzzard.
BIRDS (continued)
nomenclature, any bird which has one of these characteristics is clean, but to one unfamiliar with them it is unclean, but if it has the two characteristics it is clean" (Ḥul. 61b–62a). However, they also posited the rule "With regard to which birds are clean we rely upon tradition. A hunter is believed when he says "my master transmitted to me that this bird is clean." R. Johanan added, "provided he was familiar with birds and their nomenclature" (Ḥul. 63b). Already in the Talmudic period varying traditions are mentioned whereby certain birds were considered permitted in one locality and forbidden in another. For this reason, at the present day the custom has been adopted to eat only such birds as have all the signs of cleanliness, and about which there is a general tradition that they are clean. In the Bible and Talmud the following birds are mentioned as clean:Vulturidae: The neck is usually bare, the bill thick and solid. The talons are blunt and only slightly inclined.
Examples: griffon vulture6, black vulture, Egyptian vulture, bearded vulture.
b) Nocturnal Birds of Prey (Strigiformes)
Possessed of large head and eyes; they have four toes, two pointing forwards and two backwards. The Mishnah (Ḥul. 3:6) declares them unclean.
Examples: owl.
c) Water and Marsh Fowls
With the exception of the goose and the duck7, they are all regarded as unclean.
Examples: stork, bittern, heron, crane, gull.
a) Columbiformes: pigeon, turtle dove, palm dove.d) Various other Birds which either have no characteristics of a clean bird, or about which there is no tradition that they are permitted.
b) Galliformes 2: hen, quail, partridge, peacock3, pheasant4.Examples: warblers, crow, swift, hoopoe, ostrich.
c) Passerinae: house sparrow5.
d) Anseriformes: domestic duck, domestic goose.
1) I.e., the rear talon is situated higher up on the leg than the other four, or the middle talon is longer than the others. This latter is characteristic of birds which eat grain and walk extensively on the ground (see *Eagle).
2) To this order belong two more domestic fowls: (a) the turkey which is today everywhere regarded as a clean bird, although a few generations ago there were localities where they refrained from eating it because of the lack of any tradition that it was clean, coming as it does from the New World. To this day the descendants of Isaiah Horowitz (the "Shelah") do not eat turkey; (b) the guinea-fowl which in some localities is regarded as clean while in others it is regarded as forbidden.
3) For the problem of its identification see*Peacock.
4) In many countries there is a tradition that the pheasant is a clean bird and permitted. See*Pheasant.
5) This is the "deror" of the Bible (Prov. 26:2; Ps 84:4). With regard to this bird also there is a tradition, particularly in Oriental countries, that it is a clean bird and permitted.
6) The signs of this bird are discussed in Hulin 61a et seq. see Tosafot, ibid 63a, s.v. nez, as to its identification.
7) In some countries there is a tradition with regard to other species of birds belonging to this and other groups that they are clean and permitted.
Characteristics: To this class belong creeping or crawling things which have short legs or none at all. As a result they move close to the ground or drag along it. They exist chiefly on dry land, and breathe with lungs. The majority lay eggs, but with a soft shell in which the white and the yolk1 are mixed. They are cold-blooded, i.e., their temperature adjusts itself to the environment. Their skin is covered with scales or with heavy platelets.
None.In the Bible reptiles are included in the general prohibition "and every creeping thing that creepeth upon the earth shall be an abomination; it shall not be eaten. Whatsoever goeth upon the belly and whatsoever goeth upon all four or whatsoever hath many feet among all creeping things that creep upon the earth, them ye shall not eat for they are an abomination." (Lev. 11:41–42)
The crocodile is forbidden in accordance with Lev. 11:12, which forbids "whatsoever hath no fins or scales in the water." Of the eight creeping things which are forbidden as food and whose carcasses defile on contact (ibid. 11:29–30), six belong to the class of Reptiles. They are the lizard, gecko, skink, monitor, tortoise and chameleon. In addition all species of snakes are forbidden food though the laws of uncleanness on contact do not apply to them. Examples: black snake viper, cobra.
1) This fact is mentioned in the Talmud (Ḥul. 64a) where a distinction is made between the eggs of birds and the eggs of reptiles.
Characteristics: Vertebrates, born in water: when adult living on dry land, in water, or both media. During the early stages of metamorphosis (larvatadpole) they breathe with gills; in the adult stage either with lungs or gills. The body temperature changes in accordance with the medium in which they live.
None.a) Apoda (without legs).
b) Tailed – salamander, newt.
c) Tailless – toad, frog1.
1) The frog, like all amphibians, is forbidden, but the Mishnah (Toh. 5:1) points out that its carcass, unlike the six reptiles mentioned above, does not convey uncleanness by contact.
Characteristics: Vertebrates, living in water and breathing through gills1. In some species the body is covered with bony or teeth-like scales; others have no scales. All possess fins2. Their body temperature changes according to their environment. They reproduce either by laying eggs or by bringing forth their young alive3.
Fish are divided into main classes:
a) Bony skeletons (about 30,000 species).
b) Cartilaginous (about 400 species).
According to the Bible those fish are permitted which have "fins and scales in the waters, in the seas and in the rivers" (Lev. 11:9; Deut. 14:9). In this category only Bony Skeletons are included, since they alone possess fins and scales. The scales must be real ones, i.e., they must overlap one another and be of bony origin and not a growth of the skin. Some scales are of minute proportions; for the fish to be clean the scales must be visible to the eye4. Some fish have scales while young but shed them later; they are clean. On the other hand there are fish which develop scales only when they grow to maturity; they are also clean5.a) Cartilaginous (Chondrichthytes)
These fish either have no scales or have thick scales like teeth, which are not however true scales as they do not overlap. They give birth to their offspring alive, or lay eggs. To this group belong all the strange-shaped fish which inhabit the ocean depths, and all species of sharks.
Example: shark, ray.
b) Cartilaginous – Bony (Chondrostei)
They also lack true scales. Their body is unprotected, except that it is partly covered with five long rows of protective matter. It is from these fish that caviar (mainly black in color) is derived.
Examples: carp, trout, salmon, herring.Example: sturgeon (controversial, see "Fish" in text).
c) Bony Skeletons (Holostei)
Fish which have no scales visible to the eye, or which have no fins.
Examples: catfish, eel.
1) An exception are the fish with lungs (Dipnoi) through which they also breathe. They are able to exist out of water. Although they have both fins and scales it appears that they are not to be regarded as fish at all, but as "creeping things," and are therefore forbidden.
2) In some cases the fins are minute, while in others they are broad and are used by the fish to crawl on the seabed. Some even use them for flying.
3) In the Talmud (Bekh. 7b) it is stated that "an unclean fish breeds, whereas a clean fish lays eggs." This rule applies to Cartilaginous fish which bear their young alive and to all bony fish in Israel, which lay eggs. In other parts of the world however there are found fish, with fins and scales, which bear their young alive. To these, for instance, belong the species of Gambusia which have been introduced in various localities as ornamental fish or as devourers of insects.
4) Even those Bony Skeletons which are considered unclean have minute scales which can be seen only through a microscope. They are regarded as being without scales.
5) As the Talmud states (Av. Zar. 39a), "Fish which have no scales at the time, but grow them later … and those which have them but shed them when drawn out of the water … are permitted." The "baraita" lists, in this category, fish such as the אֶכְּסֶפְּטִייַּס which is presumably the swordfish (Xiphias). This identification, however, is not absolutely certain and thus the permissibility of the swordfish is doubtful.
Characteristics: To this group belongs the largest number of species in the animal kingdom. They have no bony skeleton. Their skin is either bare or covered with a calciferous shell or a thick chitinous membrane. They reproduce by simple division of the body, by laying eggs or by bringing forth their offspring alive. The smallest creatures of this group are the protozoa whose existence became known only with the invention of the microscope1.
Of all the inverterbrates only a group apertaining to the order of locusts (Orthoptera) are permitted for food by the Bible. This order includes some hundreds of species (out of approximately a million other species of insects) and of it the Bible mentions only four, "Yet these may ye eat of every flying creeping thing that goeth upon all four2, which have legs above their feet, to leap withal upon the earth; even these may ye eat, the locust after its kind, etc." (Lev. 11.21–22). The Rabbis interpret the word translated "after its kind" to include others of the same order and enumerate eight species of permitted Orthoptera (Ḥul. 65a–b cf. Maim. Yad, Ma'akhalot Asurot 1:21–22). The Mishnah gives four signs whereby permitted insects may be recognised: four legs, four wings, jointed legs and the wings covering the greater part of the body (Ḥul. 3:7). Insects of the order Orthoptera develop by stages. At first they have no wings and in the course of time they develop them. For this reason it is laid down that if they have no wings at the time but grow them later, they are permitted (Ḥul. 65a). This excludes such Orthoptera as have no wings at all. Even at the present day there are Jews in Israel from oriental countries who eat such locusts about which they have a tradition as to their permissibility.All inverterbrates – with the exception of some Orthoptera – are forbidden3. Those which live in water are forbidden under the prohibition either of fish which lack fins and scales, or of "any living thing which is in the waters" (Lev. 11:10).
Those which live on land are forbidden in accordance with the prohibition against "whatsoever goeth upon the belly, and whatsoever goeth upon all four, or whatsoever hath more feet" (ibid. 11:42).
The main groups of forbidden inverterbrates are:
Leeches, Mollusks (snail, oyster, squid).
Segmented Worms, Flatworms, Jellyfish, Sponges, Protozoa .
1) Practically all protozoa are microscopic and invisible to the naked eye. it is obvious that food containing them is not thereby rendered forbidden. To the extent that they are visible, however, if it is clear that a certain food consists of protozoa, it would appear that one should refrain from eating it. Nevertheless it should be pointed out that until the last century the general opinion was that protozoa and insects are formed from non-living matter through spontaneous generation. This view is found in rabbinic literature with regard to certain insects, and on these grounds they regarded them as permitted.
2) All insects have six legs. The Bible disregards the two front legs which it regards as hands.
3) The Talmud lays down the rule with regard to all living things, including insects, "that which derives from an unclean animal is unclean," (Bekh. 1.2). The only exception is bee honey which, although it derives from the bee which is unclean, is nevertheless permitted as food, since "they gather it into their body but do not exude it from their body" (Bekh. 7b).
Human milk is of course permitted (Maim. Yad, Ma'akhalot Asurot, 3:1).
[Jehuda Feliks]

with permitted food on Passover contaminates the whole, no matter how minute the amount (see *Ḥameẓ).

Milk and Meat

"Thou shalt not seethe a kid in its mother's milk" is a prohibition repeated three times in the Pentateuch (Ex. 23:19; 34:26; Deut. 14:21). The rabbinical elaboration of this precept defines three distinct prohibitions: cooking meat and milk together; eating such a mixture; and deriving any benefit from such a mixture (Ḥul. 115b). Together these laws are known as the ordinances of basar be-ḥalav ("meat in milk"). "Milk" includes all dairy products, such as cheese, butter, sour cream, and fresh cream. To create a "fence around the law" the rabbis ordained that the separation of meat from milk must be as complete aspossible. Thus, separate utensils, dishes, and cutlery must be used for dairy foods and meat (milchig and fleishig, respectively, in Ashkenazi parlance). These must be stored separately, and when washed, separate bowls (or preferably sinks), and separate dishcloths (preferably of different colors to avoid confusion), must be used. If meat and milk foods are cooked at the same time on a cooking range or even on an open fire in a closed oven, care should be taken that the dishes do not splash each other and that the pans are covered.

According to the Talmud (Ḥul. 105a) one may not eat milk after meat in the same meal. However, strict observance demands an interval of as long as six hours between eating meat and dairy dishes. Most West European Jews wait three hours, whereas the Dutch custom is to wait one hour. It is permitted to eat meat immediately after milk dishes, provided that the mouth is first rinsed and some bread eaten (Ḥul. ibid.). After hard cheese, however, it is customary to wait a longer period (Isserles to Sh. Ar., yd 89:2). Imitation "milk" derived from coconuts and soybeans may be used with meat. Fruit, vegetables, and eggs are all neutral (parev or parve), and may be eaten together with milk or meat dishes. Fish, too, is a neutral food. However, the rabbis prohibited the eating of fish and meat together, on the grounds that such a combination impairs the health.


Strictly observant Jews drink only halav Yisrael, milk obtained and bottled under the supervision of a Jew (Av. Zar. 2:6). This ensures both that no other substances have been added to the milk, and, more particularly, that no milk of an unclean animal has been added. However, since such practices are today generally forbidden by state laws, and since, furthermore, "unclean" milk is more expensive than "clean," many authorities permit the consumption of milk which has not been supervised.

The dietary laws are exceedingly complex and a great deal of material in the Talmud is devoted to them. The tractate Ḥullin deals mainly with the subject and the Yoreh De'ah, one of the four sections of *Jacob b. Asher's Tur and the Shulhan Arukh, deals exclusively with dietary laws.


in prophetic literature

The Hebrew prophets repeatedly refer to kashrut. *Isaiah (66:17) warned that those "eating swine's flesh and the detestable thing and the mouse, shall be consumed together." *Ezekiel (4:14), in his vision, claimed, "Ah, Lord God; behold my soul hath not been polluted, for from my youth up, even till now, have I not eaten of that which dieth of itself, or is torn of beasts; neither came there abhorred flesh into my mouth." *Daniel, together with his companions Hananiah, Mishael, and Azariah, refused to partake of the "king's food" and of the "wine which he drank" (Dan. 1:8).

the second temple times

Jews endangered their lives by their faithful adherence to the dietary laws during the Syrian rule of Ereẓ Israel, especially in the reign of *Antiochusiv Epiphanes. i Maccabees (1:62–63) records, "Many of the people of Israel adhered to the law of the Lord. They would not eat unclean things, and chose rather to die." The eating of the "unclean things" was literally equated with apostasy: "*Eleazar, one of the principal scribes, a man already well stricken in years, was compelled to open his mouth and to eat swine's flesh. But he, welcoming death with renown, rather than life with pollution, advanced of his own accord to the instrument of torture" (ii Macc. 6:18). During the same period, *Hannah and her seven sons chose martyrdom rather than contravene the dietary laws. "We are ready to die," they proclaimed, "rather than transgress the laws of our fathers" (ibid. 7:2). In the epic story of *Judith and Holofernes, Judith affirms, "I will not eat thereof, what I have brought with will be enough for me" (Judith 12:2).

The Book of *Tobit states that the dietary laws were specifically designed to set the children of Israel apart from their neighbors: "All my brethren, and those that were of my kindred, did eat of the bread of the gentiles, but I kept myself from eating of the bread of the gentiles" (Tob. 1:10–11).

Some tolerant gentile rulers not only permitted, but even facilitated, the observance of the dietary laws. Thus, in 44 b.c.e., Dolabella, the Roman governor of Syria, exempted the Jews of Ephesus from military service so that they would not be compelled to desecrate the Sabbath or eat forbidden food (Jos., Ant., 14:223–30). However, as Josephus' documentation of the barbarities committed during the Jewish revolt reveals, such remarkable instances of Roman tolerance were unfortunately rare. The *Essenes, on the contrary, were singled out for special savagery. "They were racked and twisted, burnt and broken, and made to pass through every instrument of torture in order to induce them to blaspheme their lawgiver and to eat some forbidden thing; yet they refused to yield to either demand, nor even once did they cringe to their persecutors or shed a tear. Smiling in their agonies, mildly deriding their tormentors, they cheerfully resigned their souls, confident that they would receive them back" (Jos., Wars, 2:152–3).

in medieval times

Despite the difficulties, and even dangers, inherent in the observance of the dietary laws during subsequent periods of severe persecution, the Jews steadfastly remained faithful to kashrut. A Jewish chronicler of the period of the Crusades writes: "It is fitting that I should recount the praises of those who were faithful. Whatever they ate or drank, they did at the peril of their lives. They would ritually slaughter animals for food according to Jewish tradition and remove the fat and inspect the meat in accordance with the prescription of the sages. Nor did they drink the wine of the idol worshipers" (Chronicle of Solomon b. Samson, in: A.M. Habermann, Gezerot Ashkenaz ve-Zarefat (1945), 57). The heroism of the medieval *Marranos in defense of the dietary laws was matched by the devotion of the *Cantonists and the inmates of the Nazi concentration camps.

Attempts to Explain the Dietary Laws

Throughout the ages, many attempts have been made to explain the dietary laws. The Pentateuch itself does not explain them, although in three separate passages in the Bible they are closely associated with the concept of "holiness." Thus, Exodus 22:30 states: "And ye shall be holy unto Me; therefore ye shall not eat any flesh that is torn of beasts in the field; ye shall cast it to the dogs." Leviticus repeats the idea: "For I am the Lord your God; sanctify yourselves therefore, and be ye holy, for I am holy; neither shall ye defile yourselves with any manner of swarming thing that moveth upon the earth" (Lev. 11:44–45). Finally, Deuteronomy 14:21 states: "Ye shall not eat of any thing that dieth of itself; thou mayest give it unto the stranger that is within thy gates, that he may eat it; or thou mayest sell it unto a foreigner; for thou art a holy people unto the Lord thy God." The Pentateuch classifies the dietary laws as ḥukkim, "divine statutes," which by definition are not explained in the text (Yoma 67b). It has been variously suggested that the underlying motivation for the dietary laws are hygienic and sanitary, aesthetic and folkloric, or ethical and psychological.

moral effects

In Ezekiel 33:25, the prophet equates the eating of blood with the sins of idolatry and murder. One interpretation of this verse teaches that the dietary laws are ethical in intent, since abstention from the consumption of blood tames man's instinct for violence by instilling in him a horror of bloodshed. This is the view expressed in a letter by *Aristeas, an unknown Egyptian Jew (probably of the first century b.c.e.), who states that the dietary laws are meant to instill men with a spirit of justice, and to teach them certain moral lessons. Thus, the injunction against the consumption of birds of prey was intended to demonstrate that man should not prey on others (Arist. 142–7). *Philo, the Alexandrian Jewish philosopher, also suggests that creatures with evil instincts are forbidden lest men, too, develop these instincts (Spec. 4:118).

The rabbis of the Talmud rarely attempted to find rational explanations for the dietary laws, which they generally regarded as aids to moral conduct. "For what does the Holy One, Blessed be He, care whether a man kills an animal by the throat or by the nape of its neck. Hence its purpose is to refine man" (Gen. R. 44:1; Lev. R. 13:3). Commenting on the verse "and I have set you apart from the peoples, that ye should be mine" (Lev. 20:26), the Sifra (11:22), a halakhic Midrash on Leviticus, states, "Let not a man say, 'I do not like the flesh of swine.' On the contrary, he should say, 'I like it but must abstain seeing that the Torah has forbidden it.'"

effects on the soul of man

Such mystics as Joseph *Gikatilla and Menahem *Recanati maintained that food affects not only the body but also the soul, clogging the heart and dulling man's finer qualities. Isaac b. Moses *Arama stated that, "The reason behind all the dietary prohibitions is not that any harm may be caused to the body, but that these foods defile and pollute the soul and blunt the intellectual powers, thus leading to confused opinions and a lust for perverse and brutish appetites which lead men to destruction, thus defeating the purpose of creation" (Akedat Yiẓḥak, Sha'ar Shemini, 60–end).

Samson Raphael *Hirsch wrote, "Just as the human spirit is the instrument which God uses to make Himself known in this world, so the human body is the medium which connects the outside world with the mind of man … Anything which gives the body too much independence or makes it too active in a carnal direction brings it nearer to the animal sphere, thereby robbing it of its primary function, to be the intermediary between the soul of man and the world outside. Bearing in mind this function of the body and also the fact that the physical structure of man is largely influenced by the kind of food he consumes, one might come to the conclusion that the vegetable food is the most preferable, as plants are the most passive substance; and indeed we find that in Jewish law all vegetables are permitted for food without discrimination" (Horeb, section 454, Eng. tr. by I. Gruenfeld (1962), 328).

hygienic explanations

Maimonides (Guide, 3:48) noted that "These ordinances seek to train us in the mastery of our appetites. They accustom us to restrain both the growth of desire and disposition to consider the pleasure of eating as the end of man's existence." He also maintained, however, that all forbidden foods are unwholesome: "All the food which the Torah has forbidden us to eat have some bad and damaging effect on the body … The principal reason why the Law forbids swine's flesh is to be found in the circumstances that its habits and its food are very dirty and loathsome" (ibid., 3:48). He gives an explanation entirely based on hygienic considerations, for the injunction against the consumption of sacrificial fat (ḥelev): "The fat of the intestines is forbidden because it fattens and destroys the abdomen and creates cold and clammy blood." Concerning the proscription of basar be-ḥalav, Maimonides states: "Meat boiled in milk is undoubtedly gross food, and makes a person feel overfull." He adds, however, "I think that most probably it is also prohibited because it is somehow connected with idolatry. Perhaps it was part of the ritual of certain pagan festivals. I find support for this view in the fact that two of the times the Lord mentions the prohibition, it is after the commandment concerning our festivals. 'Three times a year all your males shall appear before the Lord God' (Ex. 17:23–24; 23:17). That is to say, 'When you come before Me on your festivals, do not prepare your food in the manner in which the heathens do'" (ibid., 3:48). Ancient inscriptions unearthed by archaeologists (e.g., at Ras Shamra-*Ugarit) tend to confirm that this was a fertility rite. J.G. Frazer, quoting a Karaite medieval author, writes: "There was a custom among the ancient heathens, who when they had gathered all the crop, used to boil a kid in its mother's milk" (Folklore in the Old Testament, 3 (1919), 117).

Abraham *Ibn Ezra maintained that the reason for the prohibition of basar be-ḥalav was "concealed," even from the eyes of the wise, although he added "But I believe it is a matter of cruelty to cook a kid in its mother's milk" (Commentary to Ex. 23:19; see: *Animals, Cruelty to). A contemporary interpretation, advanced by A.J. *Heschel, explains that the goat provides man with the perfect food – milk, which is the only food that can sustain the body by itself. It would, therefore, be an act of ingratitude to take the offspring of such an animal and cook it in the very milk which sustains us.

Many other scholars, however, followed in the footsteps of Maimonides. They pointed out that certain animals harbor parasites that create and spread disease. It was a fact that during the Middle Ages Jews were less prone than their neighbors to the many epidemics of the time. R. *Samuel b. Meir declared that "All cattle, wild beasts, fowl, fishes, and various kinds of locusts and reptiles which God has forbidden to Israel, are indeed loathsome and harmful to the body, and for this reason they are called 'unclean'" (Commentary to Lev. 11:3).

Commenting on the verse "Whatsoever hath fins and scales in the waters, in the seas, and in the rivers, them may ye eat" (Lev. 11:9), Naḥmanides states: "Now the reason for specifying fins and scales is that fish which have fins and scales get nearer to the surface of the water and are found more generally in freshwater areas … Those without fins and scales usually live in the lower muddy strata which are exceedingly moist and where there is no heat. They breed in musty swamps and eating them can be injurious to health." Many modern scholars give hygienic reasons for the dietary laws, since it is known that bacteria and spores of infectious diseases circulate through the blood.

Modern Views on the Dietary Laws

The dietary laws were on the agenda of the rabbinical conference held in Breslau on July 12–24, 1846. The Reform Movement appointed a committee consisting of S. Adler, D. Einhorn, L. Herzfeld, S. Hirsch, and S. Holdheim to examine this aspect of Jewish tradition. In his report published in Sinai (1859 and 1860), Einhorn stated that the dietary laws (with the exception of the prohibition to consume blood and animals that died a natural death) were directly related to the levitical laws of purity and the priestly laws of sacrifice and were, therefore, of a mere temporary ceremonial character and not essentially religious or moral laws. At the Pittsburgh Conference (November 16–18, 1885), the Reform Movement resolved: "We hold that all such Mosaic rabbinical laws as regarding diet … originated in ages and under the influence of ideas entirely foreign to our present mental and spiritual state. They fail to impress the modern Jew with a spirit of priestly holiness; their observance in our days is apt rather to obstruct than to furthermodern spiritual elevation." However, the Pittsburgh Platform did not prevent Reform Jews and Reform congregations from adopting and observing the dietary laws and some have always done so. By the late 20th century, Reform Judaism had developed a more positive attitude towards observance of kashrut as part of a larger pattern of return to traditional practices. Thebasic Reform philosophy as stated in such Union of Reform Judaism publications as Gates of Mitzvah (ed. S. Maslin, 1979) is that it is a Reform Jew's responsibility to study and consider the laws of kashrut so as to develop a valid personal position. Publications of the URJ between 2000 and 2005 suggested that Reform Jews seriously consider their dietary choices and the rationales behind them and consider whether adopting some or all of the Jewish dietary laws would enhance their domestic practice of Judaism and their spiritual lives. Out of respect for the larger Jewish community as well as their own members who observe kashrut, many Reform synagogues now maintain kosher kitchens.

The Conservative position is set out in such publications as The Jewish Dietary Laws, by Samuel H. Dresner, and A Guide to Observance, by Seymour Siegel (both in one volume, 19662). Dresner, for instance, maintains that "kashrut is one of the firmest ramparts of the pluralistic aspect of Judaism. It demands sacrifice, self-discipline and determination – but what that is really worthwhile in life does not? It demands thecourage to turn our face against the powerful current of conformity that almost overcomes us daily. The goal of kashrut is holiness, a holy man and a holy nation. It is part of Judaism's attempt to hallow the common act of eating which is an aspect of our animal nature. It likewise sets us apart from the nations. Thus it achieves its objective, holiness in these two ways, both of which are implied in the Hebrew word kadosh: inner hallowing and outer separateness."

[Harry Rabinowicz /

Rela Mintz Geffen (2nd ed.)]

Women and Dietary Laws

The scrupulous daily observance of kashrut in the home has necessarily been in the hands of women as preparation of meals was traditionally designated part of "women's work." Until contemporary times, observant Jews did not eat food outside their homes unless it was in the home of a relative or of another Jew whose observance was trusted or they were ill or found themselves in dangerous circumstances. Although supervision (hashgaḥah) of food for sale to the public was in the hands of men, as was slaughter (sheḥitah) in most cases, the maintenance of proper utensils, the purchase of food, the separation of meat and dairy, the ritual salting and soaking of meat, and the cooking and serving of the food were in the hands of women. Moreover, transmission both of mundane and esoteric knowledge of these domestic processes to the next generation of daughters was entrusted to their grandmothers, mothers, and other female relatives. Communities and families had to trust and rely on women for meticulous observance, particularly in the preparation for and during the holiday of Passover.

Eloquent testimony to the devotion of Jewish women to the maintenance of the dietary laws is found throughout Jewish history. Unfortunately, this often meant the willingness to suffer when various oppressors tried to break the will of Jews by forcing them to violate kashrut, particularly by eating pork, as in the examples of Hannah and her seven sons and of Judith in Second Temple times, cited above. Research into Inquisition documents has shown that women were strong defenders of domestic Judaism, including kashrut, and that even as *Crypto-Jews who had been forced into conversion they perpetuated some of the dietary laws whenever possible.

In later eras in Western Europe, when urbanization and secularization and the drive to rise in the society led to widespread acculturation and assimilation, particularly among middle class Jews, it was frequently the women in these families who were the last to give up observance of domestic ritualpractices, including the dietary laws. A decline in traditional Jewish practice, including kashrut, accompanied the breakdown of traditional shtetl culture, growing urbanization in Eastern Europe, and the dislocations caused by immigration to America and other havens. Jewish leaders exhorted women to maintain kashrut in books, newspapers, and magazine articles in Yiddish and English that stressed female responsibility for maintaining the dietary laws. In the first decade of the 20th century Jewish women in New York City successfully organized a boycott of kosher butcher shops to counteract the precipitous rise in the price of kosher meat. Their actions became the model for kosher boycotts elsewhere, as well as other political activism of the time in support of suffrage and against exorbitant rents in immigrant neighborhoods, particularly the Lower East Side of Manhattan.

Food, Jewish law, and ritual are inextricably entwined at the very heart of the Jewish calendar and life cycle observances. In these arenas women were the facilitators rather than the public actors, even in the home. Wives arduously prepared Passover seder meals while husbands led the rituals. Somewhat ironically, the foods associated with various holidays as well as their modes of preparation have been shaped by the astonishing variety of societies, cultures, and areas of the world within which Jewish communities have been situated over the centuries. The women who have largely been responsible for Jewish cuisine have shown enduring creativity in adapting local delicacies and food ways to kashrut. Breads such as maẓẓah or ḥallah may be common to all, but the doughnuts fried in oil by Jewish women in the Ottoman Empire were a world away from the potato pancakes fried in oil to commemorate the miracle of Hanukkah in East European Jewish households. Even in 21st-century Israel, diverse laws governing the eating of kitniy yot (pulses and legumes including peas, rice, and corn) on Passover divide supermarkets and extended families in which Ashkenazi Jews have married Sephardi Jews.

Observance of the dietary laws by adults is an individual or couple's decision in an open society. However, because of the persistence of traditional gender role definitions in contemporary culture, it is generally Jewish women who continue to preside over the preparation of food, whether in households fully committed to the observance of Jewish law or in those where observance of the dietary laws is partial or mostly symbolic. Thus, the special historic connection of women to kashrut continues in the 21st century.

Dietary Laws and Jewish Culture

Jewish food, other than maẓẓah, was never standardized. In fact, in the contemporary world, the trend is to devise versions of a multitude of ethnic foods which comply with the laws of kashrut. Kosher pizza, Chinese, Japanese, and Indian food, or popular items such as sushi, parve ice cream, and margarine, and an American Thanksgiving dinner with the trimmings, may all be prepared in accordance with the dietary laws. Kosher restaurants specializing in a variety of cuisines are found in cities with substantial Jewish populations around the world and in the heart of Jerusalem, while recent kosher cookbooks offer recipes for dishes from many different ethnic fares.

Observance of the dietary laws, along with Sabbath observance connected to ritually infused meals, especially the Friday night dinner, are critical markers of Jewish identity in contemporary society. In the Diaspora in particular, they signal a willingness to maintain a particularistic identity in a multicultural society. For instance, in the demographic surveys through which American Jewish identification was analyzed from 1971 through 2001, observance of the dietary laws in the home is strongly associated with endogamy (in-marriage), other ritual observance, synagogue affiliation, providing children with formal Jewish education, and a feeling of connectedness to Israel and of responsibility for Jews around the world.

[Rela Mintz Geffen (2nd ed.)]


S.H. Dresner, The Jewish Dietary Laws (19662); H.M. Lazarus, The Ways of her Household, 1 (1923); Outline of the Laws of Kashrut, issued by the London Beth Din and Kashrut Commission; S.L. Rubinstein, The Book of Kashrut (1967); A. Wiener, Die juedischen Speisegesetze (1895); J. Gruenfeld, The Philosophical and Moral Basis of the Jewish Dietary Laws (1961). add. bibliography: H. Diner, Hungering for America: Italian, Irish, and Jewish Foodways in the Age of Migration (2002); P.E. Hyman, Gender and Assimilation in Modern Jewish History (1995); M.A. Kaplan, The Making of the Jewish Middle Class: Women, Family, and Identity in Imperial Germany (1994); R.L. Melammed, Heretics or Daughters of Israel? The Crypto-Jewish Women of Castile (1999); L. Stern, How to Keep Kosher: A Comprehensive Guide to Understanding Jewish Dietary Laws (2004).

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