Many of my non-Jewish family members and friends have asked about how the dietary laws work. When they try to research Kashrut online they are just more confused. This is typical of resources based upon Talmudic Judaism: they are incomprehensible (not to mention utterly irrational). So I have decided to provide a general overview.
First, we should address the question of meat. The Torah divides edible animals into three categories: land mammals, birds (flying creatures), and fish (sea creatures).
Land Mammals: When it comes to land mammals YHVH has commanded the Israelites to eat only those land mammals that both chew their cud and have a cloven hoof (that is each foot has two distinct “toes”). This includes cows (also including oxen, cebus, buffalos, etc.), sheep, goats, and deer (elk, moose, etc…). Animals that are not in that group include horses and pigs, in that they do not meet these requirements.
In the US we are not trained to pay attention to the sources of our meats. Salami, pepperoni, sausage, hot dogs, and bacon are commonly made from pork, although versions of these are also sometimes made from beef, turkey, and/or chicken. Anyone wishing to observe Kashrut may wish to begin by simply identifying from which animal(s) any given meat is produced.
Birds and Flying Animals- When it comes to birds the Torah lists eight different birds and types of birds that may not be eaten. Unlike land mammals we are not given a set of criteria by which to judge the cleanliness for eating of birds. Those animals that are prohibited include kites, eagles, falcons and such. Chicken, turkey, quail, dove, pheasant, and partridge are considered Kasher.
Many of the ancient Hebrew words that refer to these birds have been lost to us. It is possible that flightless birds, such as the ostrich, are forbidden, but this is not certain. Another of the lost words may refer to aquatic birds like ducks and geese, although again this is not certain. For centuries a debate has also raged about whether chickens are permitted. We are also forbidden to eat any flying creature with four legs, the only flying animal with four legs is the Bat, it is possible that this animal was classified as a flying creature in ancient times rather than as a mammal.
Sea Creatures- As with land mammals, when it comes to sea creatures we are given a set of criteria by which to judge each species: they must have both fins and scales. Salmon, tuna, bass, trout and such are Kasher. For simplicity and expedience I will often respond that this permits us to eat fish, as most commercially available fish (at least in the US) meets these criteria. This is not accurate, however. Both the shark and catfish are fish that lack scales, but the Unagi (Anguilla japonica), a freshwater eel native to Japan, has both fins and scales despite being an eel. According to Karaite tradition, due to a phrase in the Torah, we prefer that the fish die by being removed from the water and not by any other means. Naturally, shell fish of any kind are forbidden. Some commercial fish may not be permitted, click here to learn more.
Unnatural Hybridization- Animals and plants that are created from unnatural human intervention are not permitted. Pluots, tangelos, and rutabaga are results of this kind of forbidden hybridization. This prohibition may also extend to the use of GE (Genetically Engineered) foods.
Other Foods- While uncommon in the US, the eating of reptiles, amphibians, and most insects is forbidden. Certain kinds of grasshoppers and crickets are Kasher.
Slaughter- Land mammals and birds must be slaughtered properly. They must be slaughtered in a particular way that meets the standards of the Torah and of our tradition. This method of slaughter is both humane, in that each animal dies quickly and with very little pain, and sanitary, in that all of the blood is drained from the animal (when blood remains in the meat the meat will go bad more quickly). In the US, up to this time, many of us make the compromise of eating meat from clean animals that are not properly slaughtered. This is neither in accordance with the Torah nor with our tradition, but is a convenience. I look forward to a day (coming soon) that Karaite Kasher food will be readily available to our community in the US. Naturally, most commercially available fish in the US is Kasher for Karaites.
The Talmud- The Talmud was written in the 5th Century CE although it was attributed to rabbis that lived in the years following the Temple’s destruction. There is a phrase in the Torah, that appears in three places, that states “Do not boil a calf in its mother’s milk.” This phrase is used in relation to the offerings made during the Festival of First Fruits (Shavuot). The Alexandrian Jewish philosopher Philo, who lived in the First Century CE (four centuries before the Talmud was written), attributed this commandment to animal husbandry in that no animal should be slaughtered while it is still nursing. The Talmudic authors believed this commandment requires that one may not eat dairy and meat at the same meal or have them make any kind of contact with one another.
Since Philo had never heard of this rule, and he was quite thorough in his description of Jewish practices, whether or not he agreed with them, it is reasonable to assume that this is yet another case of Rabbis adding commandments to the Torah. The historian Josephus also made no mention of this practice. Karaites do not observe this practice because it is not derived properly from the scriptures. It is more likely that the commandments prohibits the Israelites from engaging in a certain Canaanite ritual associated with Baal worship, as he was depicted as a golden calf.
Talmudic slaughter also differs from that of the Karaites. They do not make the cut as quickly as is required by Karaite tradition which can cause the animal significant pain. It is also permissible under the Talmud to kill a fish by striking it with a stick rather than allowing it to die from being removed from the water.