Kashrut: The strict dietary rules that are a part of Judaism called

January 9, 2026 •

5 min read

The Hebrew word for the set of Jewish dietary laws is "kashrut," and foods that conform to these regulations are known as "kosher". Following these strict dietary rules that are a part of Judaism is a fundamental aspect of life for many observant Jews, influencing their food preparation and consumption at every turn.

Quick Summary

Kashrut comprises the Jewish dietary laws detailing permissible and forbidden foods and their proper preparation. This system requires meticulous separation of meat and dairy, humane ritual slaughter, and inspection of all ingredients to ensure suitability for consumption.

Key Points

What are the strict dietary rules that are a part of Judaism called?: The rules are called kashrut, and food that meets the standards is referred to as kosher.
Permitted and Forbidden Animals: Kosher land animals must have both cloven hooves and chew their cud, while kosher fish must have fins and scales.
Separation of Meat and Dairy: Kashrut mandates strict separation of meat and dairy products, requiring separate kitchenware and a waiting period between consuming them.
Ritual Slaughter: Permissible animals must be ritually slaughtered by a trained shochet in a humane process known as shechita.
The Role of Blood: The consumption of blood is forbidden, and meat must undergo a salting and soaking process to remove all traces of it.
Kosher Certification: Modern packaged foods often feature a hechsher, or kosher symbol, to indicate they have been produced under rabbinic supervision.
Beyond Food: Kashrut extends to all aspects of the kitchen, including utensils, preparation surfaces, and storage, to prevent cross-contamination.

Understanding the Laws of Kashrut

Kashrut, meaning "fit" or "proper" in Hebrew, refers to the comprehensive set of Jewish dietary laws derived from the Torah and later codified in rabbinic tradition. These rules govern what food is acceptable for Jewish people to eat and how it must be prepared, transforming the everyday act of eating into a spiritual practice. Observance of kashrut is considered a mitzvah, or divine commandment, rather than a health practice, although some historical and spiritual rationales have been offered.

The Categories of Kosher Food

All foods in Judaism are categorized into three main groups, guiding how they can be combined and prepared in a kosher kitchen:

Meat (Fleishig): Includes meat and poultry from kosher animals, as well as any product made from or processed with them. This category requires strict separation from dairy products.
Dairy (Milchig): Comprises milk from kosher animals and all products derived from it, such as cheese, butter, and yogurt. Like meat, dairy must be kept separate from meat.
Neutral (Pareve): Consists of foods that are neither meat nor dairy. This includes fruits, vegetables, grains, eggs, and kosher fish. Pareve foods can be eaten with either meat or dairy, with the exception of fish, which is customarily not mixed with meat for health reasons.

Permissible and Impermissible Animals

One of the most foundational aspects of kashrut is determining which animals are fit for consumption. The Torah provides specific criteria to distinguish between kosher and non-kosher species.

Kosher Mammals: To be considered kosher, a land mammal must have both cloven (split) hooves and chew its cud. This includes animals such as cows, goats, and sheep. Conversely, pigs, rabbits, and horses are not kosher because they lack one or both of these signs.

Kosher Fish and Seafood: In the water, only creatures with both fins and scales are permitted. This means that while fish like salmon, tuna, and herring are kosher, all shellfish (e.g., shrimp, crab, lobster) and other aquatic life without scales (like catfish) are strictly forbidden.

Kosher Birds: The Torah lists specific non-kosher bird species, which are typically predators or scavengers. Common domesticated fowl like chickens, ducks, geese, and turkeys are traditionally accepted as kosher.

The Process of Ritual Slaughter (Shechita)

Even a kosher animal must be slaughtered and prepared according to Jewish law to be considered acceptable for consumption. This ritual slaughter, known as shechita, is performed by a specially trained and pious individual called a shochet. The process involves a swift, deep, and painless cut to the animal's throat using a perfectly sharp, smooth knife (chalef). This method is designed to be as humane as possible, causing an immediate loss of consciousness. Animals that die naturally or are killed by other means are not kosher.

Following shechita, the animal is inspected for any internal flaws or diseases (bedika) that would render it non-kosher, or treif. Parts of the animal that are forbidden for consumption, such as certain fats (chelev) and the sciatic nerve (gid hanasheh), must also be removed.

The Prohibition of Blood

One of the most emphasized rules in kashrut is the prohibition against consuming blood. This is because the Torah associates the life or soul of the animal with its blood. To comply, all blood must be removed from the meat before cooking. This is typically done through a process called meliḥah, which involves soaking and salting the meat. The liver, which is particularly blood-rich, must be broiled over an open flame.

Separating Meat and Dairy

The strict separation of meat and dairy is one of the most visible aspects of kashrut, derived from the Torah's repeated command, "You shall not boil a kid in its mother's milk". Observant Jews adhere to this principle by:

Separate Utensils: Maintaining two completely separate sets of kitchenware—pots, pans, dishes, and cutlery—one for meat and one for dairy. In some homes, this extends to separate sinks and dishwashers.
Waiting Periods: Observing a waiting period after eating meat before consuming any dairy products. The length of this waiting period varies by tradition, typically between three and six hours. A much shorter, or no, wait is required when switching from dairy to meat.

Kosher Certification in the Modern World

As food processing has become more complex, rabbinic supervision has become essential. Kosher certification agencies provide oversight to ensure food products meet kashrut standards. Consumers can identify certified products by a hechsher, or kosher symbol, on the packaging. The most widely recognized symbol in the United States is the O-U, a 'U' inside a circle, from the Orthodox Union. Other symbols and variations exist to indicate whether a product is meat (OU-M), dairy (OU-D), fish (OU-F), or kosher for Passover (OU-P).

Comparison of Kosher and Non-Kosher Food Rules


Aspect	Kosher	Non-Kosher (Treif)
Land Animals	Must chew cud AND have cloven hooves (e.g., cow, goat).	Lacks one or both signs (e.g., pig, horse, rabbit).
Aquatic Life	Must have fins and scales (e.g., salmon, tuna).	No fins or scales (e.g., shellfish, eel, catfish).
Preparation	Ritual slaughter (shechita), blood drained, internal inspection.	No required preparation method; can be killed by other means.
Meat & Dairy	Strict separation required; separate utensils and preparation areas.	No restrictions on mixing meat and dairy products.
Blood Consumption	Forbidden; meat must be processed to remove all blood.	No prohibition on consuming animal blood.

Conclusion: A Path to Holiness

The strict dietary rules that are a part of Judaism, known as kashrut, are a profound way for observant Jews to infuse daily life with spiritual significance. Beyond simply restricting certain foods, these laws dictate a thoughtful and intentional approach to eating, impacting everything from the choice of animals to the organization of a kitchen. By observing kashrut, followers reaffirm their covenant with God and maintain a tangible link to millennia of tradition. While a challenge in the modern world, the widespread availability of kosher-certified products and the guidance of rabbinic authorities help millions of Jews worldwide to uphold this meaningful practice.

Resources

For more in-depth information on the laws and philosophy behind Jewish dietary practices, a comprehensive resource can be found at Chabad.org's guide to kosher.

Frequently Asked Questions

Kashrut is the Hebrew word for the set of Jewish dietary laws themselves, while kosher describes a food or product that is prepared and fit for consumption according to those laws.

The separation of meat and dairy stems from a passage in the Torah, repeated three times, that says, "You shall not boil a kid in its mother's milk". Rabbinic tradition interprets this as a prohibition against mixing meat and dairy products in any way, from cooking to eating.

A pareve food is a neutral item that is neither meat nor dairy, such as fruits, vegetables, grains, and eggs. Because they are neutral, they can be eaten with either meat or dairy meals.

No, only fish that have both fins and scales are considered kosher. This means that seafood like shellfish, shrimp, lobster, and aquatic mammals like dolphins are not kosher.

If a non-kosher item comes into contact with a kosher item, particularly in the presence of heat, the kosher item can lose its kosher status. This is why observant Jews use entirely separate sets of kitchenware for meat and dairy, and for Passover.

No, kosher is not a cooking style. Any cuisine, from Chinese to Italian, can be kosher if it is prepared in accordance with the laws of kashrut. The certification applies to the ingredients and preparation methods, not the recipe itself.

A kosher symbol, or hechsher, is an official certification from a rabbinic organization indicating that the product complies with kosher dietary laws. It assures the consumer that the product's ingredients and manufacturing process meet the required standards.