For meat to be kosher, the animal itself must be a permitted species, it must be slaughtered by a trained religious slaughterer using a specific method, its blood must be fully removed, and certain fats and nerves must be extracted before the meat can be eaten. Kosher isn’t a single rule but a chain of requirements, and if any link breaks, the meat is not kosher regardless of everything else done correctly.
Which Animals Qualify
The Torah sets two requirements for land animals: the animal must chew its cud (regurgitating food from its first stomach to chew again) and have completely split hooves. Both traits must be present. Cows, goats, sheep, and deer meet both criteria. Horses and donkeys fail on both counts. The pig is the most frequently cited example of an animal that meets one test but not the other: it has split hooves but does not chew its cud, so it is not kosher. The camel is the reverse, chewing cud but lacking split hooves.
For birds, the Torah takes a different approach. Rather than listing physical traits, it names 24 categories of non-kosher birds, which are primarily birds of prey. The rabbis of the Mishnah later identified physical signs to help classify birds not explicitly named: a kosher bird should not be predatory, and it should have an extra toe, a crop (a pouch that stores food before digestion), and a gizzard with a lining that peels off by hand. In practice, Jewish communities eat birds with an established tradition of being considered kosher, which is why chicken, turkey, duck, and goose are widely accepted.
Fish must have both fins and scales to be kosher, which is why shellfish, shrimp, and catfish are all excluded. But since the reader’s question is about meat specifically, the real complexity lies in what happens after the animal is selected.
How the Animal Must Be Slaughtered
Kosher slaughter, called shechita, can only be performed by a shochet, a person who has undergone years of specialized training. A shochet studies the religious laws governing slaughter, learns animal anatomy and pathology, and serves an apprenticeship under an experienced practitioner. Before being certified, the trainee must successfully perform the slaughter three consecutive times in front of an expert. The shochet also needs sharp tactile perception to inspect the knife, which must be perfectly smooth with no nicks or imperfections.
The slaughter itself uses a single, rapid cut across the throat with an extremely sharp blade, severing the trachea and esophagus. Five specific rules govern the cut: no pausing mid-stroke, no pressing or chopping (the motion must be a smooth draw), the cut cannot go beyond the designated area of the neck, the blade cannot be covered or hidden by wool or skin during the cut, and the trachea and esophagus cannot be torn rather than cleanly severed. If any of these rules are violated, the meat is not kosher.
Inspection After Slaughter
After slaughter, the animal’s internal organs are inspected in a process called bedikah. The lungs receive the most scrutiny. Inspectors look for punctures, missing tissue, hardened spots, blisters, adhesions filled with pus, unusual coloring, or dried-out tissue. Any of these defects can render the entire animal non-kosher.
This is where the term “glatt” comes in. Glatt literally means “smooth” in Yiddish and refers to lungs that are completely free of adhesions. Technically, some adhesions can be removed and tested, and if the lung still holds air, the meat can still be considered kosher under certain standards. But glatt kosher means the lungs were smooth from the start, with no adhesions at all. In the United States, most kosher meat sold today is labeled glatt, reflecting a stricter standard that has become the mainstream expectation.
Removing Forbidden Parts
Even after an animal passes inspection, not all of its meat is permitted. Two categories of tissue must be removed: certain fats (called chelev) and the sciatic nerve.
The prohibition on the sciatic nerve comes from the story of Jacob wrestling with an angel and being struck in the hip. Every trace of the sciatic nerve and the fat surrounding it must be extracted, along with the outer sinew of the thigh tendon. This removal process is called nikkur (also known as porging or deveining), and it requires genuine expertise. The work is so painstaking, particularly in the hindquarters, that in many Western countries kosher producers simply sell the hindquarters to the non-kosher market rather than perform the removal. This is why kosher beef tends to come from the front of the animal: brisket, chuck, rib, and shoulder cuts.
The forbidden fats are distinct from the fat you see marbled through a steak. Chelev refers to specific layers of fat surrounding the stomach, kidneys, and loins. These must be carefully separated from the permitted fat and discarded.
How Blood Is Removed
The Torah prohibits consuming blood, so all remaining blood must be drawn out of the meat before cooking. This is done through a soaking and salting process that follows a specific sequence.
First, the meat is submerged in cold water for at least 30 minutes to loosen residual blood. Then it is thoroughly coated in coarse-grained kosher salt. The large crystals are essential here because they draw blood out steadily without dissolving too quickly the way fine table salt would. The salted meat sits for about one hour, then is rinsed thoroughly to remove both the salt and any extracted blood. This entire process must be completed within 72 hours of slaughter, before the blood has a chance to dry and set into the tissue.
An alternative method for removing blood is broiling the meat over an open flame, which is the required method for liver, since liver contains so much blood that salting alone is considered insufficient.
Keeping Meat and Dairy Separate
Kosher law prohibits mixing meat and dairy, and this extends well beyond the plate. Meat and dairy require separate cookware, dishes, utensils, and even sponges. If a dairy product is cooked in a meat pot, both the food and potentially the pot become non-kosher.
After eating meat, the standard practice is to wait six full hours before consuming any dairy. This waiting period allows time for meat residue to clear from the teeth and digestive system. Some Jewish communities have established shorter waiting periods, but six hours is the most widely observed standard. Going the other direction, from dairy to meat, is faster: you eat something neutral (pareve), rinse your mouth or take a drink, wash your hands, and you can proceed. Many communities add a wait of 30 minutes to an hour. The exception is aged hard cheese, which requires the same six-hour wait before eating meat.
Certification and What Labels Mean
In practice, most consumers rely on kosher certification symbols (called a hechsher) to know whether meat meets all these requirements. A rabbinic organization supervises every stage of production, from slaughter through packaging, and places its symbol on the label. The most widely recognized symbol in the United States is the OU (Orthodox Union), where “OU-Meat” or “OU-Glatt” on a package indicates the product is certified kosher meat or contains meat-derived ingredients. Other major certifying agencies include the OK, Star-K, and Kof-K, each with its own symbol.
These symbols represent a complete chain of supervision. A mashgiach (kosher supervisor) is typically present at the slaughterhouse, during inspection, and at the processing facility. The certification covers not just the meat itself but the equipment it contacts and the other products made in the same facility. Meat without a recognized hechsher, even if it comes from a permitted species, is not considered kosher by observant consumers because there is no verification that every step in the chain was followed correctly.