Kashrut
The Torah's books of Leviticus and Deuteronomy establish the core dietary laws that define kosher food. These ancient texts prohibit the consumption of specific animals, such as pork, frogs, and shellfish. They also forbid eating blood from any creature. The details of these laws are not fully explained in the biblical text itself. Later rabbinical literature, including the Mishnah and Talmud, expanded upon these basic principles to create a complex system of rules. Maimonides, writing in his Guide for the Perplexed in 1956, noted that some scholars view these laws simply as tests of obedience without rational explanation. Other theologians have argued that the laws serve symbolic purposes or offer practical health benefits. The Babylonian Talmud, specifically Hullin 13a, discusses the prohibition against consuming meat slaughtered by non-Jews. This historical development transformed simple prohibitions into a comprehensive legal framework governing Jewish life.
Mammals must possess two specific physical traits to be considered kosher: they must chew their cud and have cloven hooves. Animals like pigs lack one trait while camels lack the other, rendering them forbidden. In 2008, a rabbinical ruling determined that giraffes meet both criteria and are eligible for kosher status. Their milk was found to curdle according to kosher standards, though the animal is rarely slaughtered today due to safety concerns. Birds require an established tradition permitting their consumption even if they display four specific signs described in the Mishnah. These signs include an extra toe, a crop, and a gizzard with a peelable lumen. Fish must have both fins and scales to be permitted. Shellfish and all water creatures lacking these features are strictly prohibited. Insects are generally forbidden except for certain types of locusts, though most communities lack a clear tradition regarding which species qualify. The Shulchan Aruch, Yoreh De'ah 79, details these zoological requirements for mammals and birds.
A trained ritual slaughterer known as a shochet performs the act of shechita using an ultra-sharp instrument called a chalaf. This process severs the trachea, esophagus, carotid arteries, and jugular veins in a single continuous cut. Failure to meet any of these technical criteria renders the meat non-kosher. After slaughter, the body undergoes inspection to confirm no medical defects existed that would cause death within a year. The blood must be removed through soaking and salting or by broiling and roasting. Liver requires special treatment because it is rich in blood; it is grilled over an open flame instead of salted. The Talmudic text Hullin 13a mandates that meat from animals slaughtered by non-Jews is forbidden. Some animal rights activists view this method as cruel, claiming the animal may not lose consciousness immediately. The Shulchan Aruch, Yoreh De'ah 66, 78, outlines the procedures for removing blood from various parts of the animal.
Meat and milk derivatives cannot be mixed in cooking, dining, or storage. Observant Jews maintain separate sets of dishes and sometimes different kitchens for meat and dairy products. They wait anywhere between one and six hours after eating meat before consuming milk products. The Shulchan Aruch, Yoreh De'ah 87 et seq recommends a six-hour waiting period during which brushing teeth and rinsing the mouth are generally advised against. Shelomo Dov Goitein noted that early Middle Ages Jewish families kept only one set of cutlery until the late 14th and 15th centuries when separate utensils became common practice. David C. Kraemer's research confirms this timeline of separation development. Utensils used for non-kosher foods become non-kosher themselves unless purified through boiling water or blowtorches. This strict dichotomy creates distinct categories for food preparation and consumption within observant households.
Rabbinical agencies issue certificates known as hechsherim to certify products as kosher. These symbols indicate compliance with dietary laws and appear on packaging like the U inside a circle used by the Orthodox Union. Manufacturers contact religious authorities who inspect production methods before issuing certification. In Britain, the London Beth Din uses a KLBD logo while Manchester Beth Din employs an MK symbol. Changes in manufacturing processes can render previously certified products non-kosher if ingredients change. An active grapevine among the Jewish community discusses questionable products and those that have recently gained certification. The cost of certification for mass-produced items is typically minuscule compared to potential revenue gains. The Orthodox Union claims kosher products perform better than competing brands when positioned next to them. In 2014, the Israeli Defense Forces allowed female kosher supervisors to work in military kitchens for the first time.
Food producers began advertising kosher status as early as 1849 to expand their markets. Procter & Gamble became the first company to advertise Crisco as kosher in 1911. Hebrew National hotdogs launched a campaign titled we answer to a higher authority in the 1960s appealing to both Jews and non-Jews. Menachem Lubinsky estimates there are millions of kosher consumers generating billions in sales within the United States alone. Only 15% of kosher consumers were Jewish according to a 2012 analysis of the specialty food market in North America. Muslims often consume kosher meat when halal options are unavailable. Seventh-day Adventists follow similar dietary laws while vegetarians use pareve designations to avoid dairy derivatives. Surveys from 2013 and 2020 found 22% of American Jews keep kosher at home. About one-sixth of American Jews fully observe these laws while many others abstain from specific prohibited foods like pork. The economic impact extends beyond religious communities into broader consumer markets seeking quality assurance through certification symbols.
Common questions
What books of the Torah establish kosher dietary laws?
The books of Leviticus and Deuteronomy establish the core dietary laws that define kosher food. These ancient texts prohibit the consumption of specific animals such as pork frogs and shellfish while also forbidding eating blood from any creature.
Which physical traits must mammals possess to be considered kosher?
Mammals must possess two specific physical traits to be considered kosher: they must chew their cud and have cloven hooves. Animals like pigs lack one trait while camels lack the other rendering them forbidden.
How does a shochet perform ritual slaughter according to Jewish law?
A trained ritual slaughterer known as a shochet performs the act of shechita using an ultra-sharp instrument called a chalaf. This process severs the trachea esophagus carotid arteries and jugular veins in a single continuous cut.
Why can meat and milk derivatives not be mixed in cooking or dining?
Meat and milk derivatives cannot be mixed in cooking dining or storage because observant Jews maintain separate sets of dishes and sometimes different kitchens for meat and dairy products. They wait anywhere between one and six hours after eating meat before consuming milk products.
What is the purpose of hechsherim certificates issued by rabbinical agencies?
Rabbinical agencies issue certificates known as hechsherim to certify products as kosher so that symbols indicate compliance with dietary laws on packaging. Manufacturers contact religious authorities who inspect production methods before issuing certification.