What Makes Food Kosher?

You may have seen “kosher-style” delis or heard that some foods are kosher, while others are not. It’s universally known that Jews don’t eat pork, but beyond that, what does kosher actually mean?

Learn more about kosher laws so you can determine whether or not a food is kosher and how to keep a kosher diet if you’d like.

What does the word “kosher” mean?

Kosher is a Hebrew word with a few different translations: “prepared,” “fit,” or “appropriate.” It essentially means food that a Jew is able to eat. You may have heard the word “kashrut” used, and that is the body of laws on whether or not food is kosher. The opposite of kosher is non-kosher or “treyf,” a Yiddish word for something that isn’t kosher.

What makes something kosher?

Different types of animals, fruits, and vegetables are kosher according to the Torah.

In terms of animals, they must have fully split hooves and chew their cud. They are mammals and herbivores, and include cow, sheep, and goat, but deer and buffalo can also be eaten. The Torah lists birds that are not kosher, including birds of prey like vultures and hawks, but chickens, ducks, gooses, and turkeys are kosher – as are their eggs. We do not eat animals that are aggressive and eat other animals, as we do not want to have these traits within us.

Fish must have fins and scales in order to be considered kosher, and shellfish (crabs, shrimp, lobster) and aquatic mammals (dolphins, sharks, whales) are not kosher. Tuna, flounder, salmon, whitefish, branzino, and halibut are some examples of kosher fish.

Note: Animals and birds (not fish) must be slaughtered in a kosher fashion, through a process called shechita. They are slaughtered with a knife that severs the jugular vein, resulting in a near instantaneous and painless death. If the animal had any abnormalities, it is not kosher. If it was healthy, then the meat is covered with salted and washed, which removes the blood. There is a Torah teaching not to eat an animal’s blood, and washing and salting the meat ensures this.

Where do kosher laws come from?

The laws of kashrut originate from the Torah and are fleshed out in the Talmud. While some kosher laws have an explanation behind them, others do not. For example, the Torah says not to eat pig, and this kind of law is called a “hok” – a commandment that is supra-rational.

What foods are kosher?

Foods that are kosher include kosher animals, birds, and fish, along with all fruits and vegetables in their pure state (i.e. an apple or a piece of lettuce). Fruits and vegetables must be properly washed to get rid of bugs, as it is forbidden to eat most kinds of insects.

In terms of what you’d find in the grocery store – i.e. processed foods like cereal, potato chips, and pretzels – you’ll need to check food for a reputable kosher label, called a hechsher, on products. You can see a full list of reputable hechshers here.

Products will be labeled as kosher – meat, kosher – dairy, or kosher – parve, or it won’t say meat or dairy, making it parve (for example, the OU’s hechsher). Parve means “neutral,” which means that it’s a food that’s not meat or dairy. All fruits and vegetables are parve, as are eggs.

Many products in the grocery store, including those from mainstream brands, are kosher. General Mills, Nestle, Kellogg’s, Coca-Cola, and Kraft Heinz, for example, produce thousands of kosher products you can purchase.

The laws of kashrut tell us not to mix meat and milk, so you cannot have a cheeseburger or chicken parmesan. However, you can substitute one or the other with a vegan cheese or meat and enjoy these types of foods (i.e. a hamburger with vegan cheese, or a vegan burger with real cheese). There are also rules specifying how many hours you have to wait after eating meat to then eat dairy – some people wait six hours, while others wait three hours or one hour. Ask a local Orthodox rabbi for information regarding how many hours you should wait.

When going out to eat, to properly keep kosher, you must go to a kosher restaurant. This is a restaurant that has a kosher inspector to make sure that all processes are kept correctly.

Remember that a “kosher-style” deli is not kosher, and oftentimes will have bacon on the menu. Yelp and Uber Eats are not reliable when searching for kosher restaurants, as the information is not always correct. You can find a list of legitimate kosher restaurants on YeahThatsKosher, as well ask a local Orthodox rabbi for a list.

What foods are not kosher?

Foods that are not kosher include non-kosher animals, fish, and birds like pigs, horses, whales, sharks, shrimp, crab, lobster, hawks, and eagles. Food without a hechsher – aside from fruits and vegetables – is not kosher, unless specified by an Orthodox rabbi that it’s acceptable.

Additionally, mixing meat and milk is not kosher, and food served in a non-kosher restaurant is not kosher. Food is also not kosher if there are bugs on it or if it has not been properly slaughtered.

Keeping a kosher kitchen

If you want to start keeping kosher, then it’s imperative to have a kosher kitchen. This means you have properly kashered your dishes in a mikvah, a natural body of water, and that you have separate dishes and utensils for meat and milk.

It’s ideal to have separate sinks and ovens for meat and dairy food, but you can work around this by using an insert in your sink and kashering your oven in between uses. You can never cook meat and dairy dishes in the same oven or keep meat and dairy dishes in the sink at the same time.

Getting started with kosher

Why keep kosher? It’s a way to connect with God and one of the most important aspects of Jewish law. According to Jewish mysticism, non-kosher food blocks us from truly connecting with God and our spiritual essence. Additionally, animals that were slaughtered in a kosher way have more sparks of holiness, which affects our being.

If you want to start keeping kosher, you can connect with a local Orthodox rabbi who can give you more information on this special and transformative step in your spiritual journey. Good luck, and bon appetit!