Kosher is a term to describe any food that complies with a strict set of dietary rules in Judaism. These rules are called kashrut.

Not all Jewish people observe the rules of kashrut by eating kosher food. For those who do, it is a way to show reverence to God and feel connected to their faith and their communities.

This article outlines the rules for eating a kosher diet, its origins, and the requirements a food must meet to be considered kosher.

Kosher food being prepared for passover.Share on Pinterest
Image credit: Yulia Reznikov/Getty Images

In Hebrew, “kosher” means fit. Kosher food is any food fit for consumption by Jewish people.

The laws of kosher define which foods a person can and cannot eat, and also how they should produce and handle certain foods. The laws also state which combinations of foods that people should avoid.

The Torah, the first part of the Jewish bible, lays the foundations of kosher dietary laws. Practicing Jews believe that following a kosher diet is God’s will.

The rules of kosher define what a Jewish person is allowed to eat, how they must prepare certain foods, and what foods they are allowed to combine with other foods.

The laws divide foods into three categories:

  • Meat, or fleishig: everything made from meat and poultry
  • Dairy, or milching: milk, cheese, butter, and yogurt
  • Pareve: any foods that are neither meat nor dairy, including fish, eggs, and plant-based foods.

One of the most important rules of kosher is that a person should never eat meat and dairy together. In strict kosher kitchens, people use separate utensils for meat and dairy products, which are not washed in the same water, to avoid cross-contamination.

Combining meat and food also applies within the body. After eating meat, it is customary to wait until the next meal before eating dairy, and vice versa.

Pareve foods are considered neutral, so a person can combine these with either meat or dairy. The only exception is fish, which is pareve, but people cannot eat these with meat.

Although there are fewer rules regarding pareve foods, people should still handle these carefully. For instance, if a pareve food is prepared or processed using the same equipment as meat or dairy, it should be reclassified as meat or dairy.

For meat to be considered kosher, a person needs to slaughter it in a specific manner, known as shechita. A certified person, known as a shochet, should carry out the slaughter. People can only eat the forequarters of permitted animals, while they should soak the meat before eating to remove all traces of blood.

Wine plays an important role in many Jewish religious occasions. To be considered kosher, the drink must be produced according to specific rules. All equipment used to grow, harvest, and prepare the grapes should be deemed kosher. In addition, anyone involved in making kosher wine must be a practicing Jew.

Jewish people believe that God commands kosher laws. Moses taught these rules to God’s followers and wrote the basics of the laws in the Torah. By eating kosher food, some Jewish people believe it helps them feel connected to God.

The original biblical laws were quite limited and referred almost exclusively to meat and animal products. Over the years, subsequent generations added additional laws.

As well as keeping meat and dairy separate, there are certain foods not permitted by kosher law. These include:

  • seafood that does not have fins and scales, such as shrimp, lobster, crab, and oysters
  • meat from pigs, rabbits, squirrels, camels, kangaroos, and horses
  • birds of prey or scavenger birds, such as eagles, owls, hawks, and gulls
  • the hindquarters of permitted ruminant animals. These cuts of meat include sirloin, flank, short loin, shank, and round
  • most insects are not considered kosher, so fruits and vegetables should be inspected and washed thoroughly before being eaten

People who wish to eat a strict kosher diet should be careful about cross-contamination between meat and dairy, meat and fish, and kosher foods and non-kosher foods. Foods that must not be combined should have separate equipment and preparation areas.

Although kosher laws forbid some foods, there are still many foods available.

Pareve foods

Pareve foods have the fewest restrictions, providing the producer prepares them according to kosher rules. Examples of pareve foods are:

  • fruits
  • vegetables
  • grains
  • nuts
  • seeds
  • fish
  • eggs from a kosher animal

Meat

The only kosher mammals are those that are herbivores, chew their cud — known as ruminants, and have cloven hooves. These include:

  • cow
  • goat
  • sheep
  • deer
  • addax
  • antelope
  • bison
  • gazelle
  • giraffe
  • ibex

Poultry

The Torah lists 24 species of fowl that are forbidden by kosher law. All other birds are considered kosher. In the United States, the only poultry considered kosher are:

Fish

Kosher fish must have fins and scales, and seafood that does not meet those basic requirements is not kosher. Popular kosher fish include:

  • cod
  • bass
  • herring
  • mackerel
  • salmon
  • trout
  • carp
  • flounder

Unlike meat and poultry, there are no strict rules regarding the preparation of fish.

Insects

Although there has been some debate over which insects are kosher, most kashrut organizations agree that some species of locust are permitted. Most Jews do not eat locusts, although in some Jewish communities, locusts are a traditional food.

Passover, or Pesach, is an 8-day festival that takes place in early Spring. It celebrates the freeing of Israelites from Ancient Egypt.

For people who wish to follow a kosher diet, there are special rules to follow during Passover. A person should consume no leavened grains, or “chametz”, from midday of the day before Passover until the end of the festival.

To “leaven” a bread means to make it rise. Although kosher rules permit most grains during Passover, they must not contain any yeast or have been in contact with moisture for longer than 18 minutes.

Matzo, a type of unleavened flatbread, is not considered chametz and can be eaten throughout Passover.

Other foods that are considered chametz, which kosher rules forbid during Passover, include:

  • bread
  • cake
  • cookies
  • cereal
  • pasta
  • most alcoholic drinks

Buying kosher food can present many challenges, as many foods go through complex stages of production. Each stage should conform to kosher laws by eliminating cross-contamination with non-permitted foods.

Certification ensures that foods have met all necessary requirements to be deemed kosher.

Certified food usually displays a label from one of several certifying organizations.

If food is certified for Passover, it will display a separate label.

Many Jewish people choose to eat a kosher diet as it helps them feel connected to their heritage, faith, and communities.

Despite its many restrictions, a kosher diet can offer lots of variety and nutritional balance.

Certification of kosher foods has helped make the process of buying kosher food simpler.