Jewish Dietary Laws

Understanding the rules behind kosher observance

Red Snapper, a kosher species of fish
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The laws of kashrut also referred to as the Jewish dietary laws, are the basis for the kosher observance. These rules were set forth in the Torah and elucidated in the Talmud. The Hebrew word "kasher" literally means "fit," and the kosher laws concern themselves with which foods are considered fit to eat. Those who keep kosher follow the Jewish dietary laws. 

Though the basic biblical kosher rules are unchanging, rabbinic experts continue to consider and interpret the meaning and practical application of the Jewish dietary laws in response to the new developments in industrialized food processing.

The complexity and international scope of the modern food supply have paved the way for a robust kosher certification industry, which provides food manufacturers, food service establishments and caterers with production oversight, and helps kosher consumers identify which foodstuffs are kosher with the aid of trademarked symbols that denote a certified food's kosher status.

The Jewish dietary laws explain the rules for choosing kosher animal products, including the prohibition of what is considered "unclean" animals and the mixing of meat and dairy. The laws also outline what are considered to be "neutral" foods (pareve).

Animal Products

To be considered kosher, animals must fall into one of the following categories, and meet certain requirements.

  • Certain animals may not be eaten at all. These include pigs, shellfish, rabbits, and reptiles. 
  • Mammals that have split hooves and chew their cud, (including cows, sheep, goats, bison, and deer) are kosher.
  • Fish must have fins and removable scales to be considered kosher.
  • Specific kosher bird species are listed in the Torah, but there is more ambiguity about the requirements a bird must meet to be considered kosher. Generally speaking, birds of prey are not kosher. 
  • Milk and eggs from kosher animals are kosher. Eggs must generally be checked to ensure they do not contain blood, which is not kosher. 

Of the animals that may be eaten, the birds and mammals must be slaughtered in accordance with Jewish law, a process known as shechita. Certain parts of permitted animals may not be eaten. Also, all blood must be drained from the meat or broiled out of it before it is eaten.

Meat and Dairy

Any meat (the flesh of birds and mammals) cannot be eaten with dairy. Utensils that have come into contact with meat (while hot) may not be used with dairy and vice versa. In addition, utensils that have come into contact with non-kosher food (while hot) may not be used with kosher food.

Pareve Foods

Kosher food is divided into three categories: meat, dairy and pareve. The pareve foods are considered neutral and can be eaten with either milk or meat.

  • All fruits, vegetables, grains, pasta, nuts, beans, and legumes are kosher. Note, however, that with the exception of a small number of locust species, bugs are not kosher. As a result, the use of certain fruits and vegetables is now considered controversial in certain Orthodox circles, over concerns about insect infestation. 
  • Eggs, fruits, vegetables, and grains are considered pareve, or neutral, and can be eaten with either meat or dairy. Fish is also considered pareve, but some kosher observant Jews do not cook or eat fish with meat.
  • Grape products (including juice and wine) must be produced by Jews in order to be considered kosher.