Standards and Regulations

Fish with both scales and fins are kosher, while fish with only fins are not. There are four types of fish scales: clenoid, round, hard, and scutes. According to the law, only the first two types are kosher. Clenoid scales are those found on sturgeons, and scutes are those found on sharks. Unlike animal blood, fish blood is permissible and does not require a specific slaughtering method. Fish scales must be genuine scales, and their removal must not damage the skin. As the law states, "Those fish that have scales and fins are permissible for you..." (Vayikrah 11:9-12). Joints, scutes, and spiny scales are not considered scales because their removal would damage the skin. Therefore, fish with scutes, such as eels, bream, sharks, sturgeons, and swordfish, are not considered kosher.

Crustaceans and mammals such as sharks and dolphins are non-kosher. Only the eggs, or roe, of kosher fish are permitted, so supervision is essential. Be careful when purchasing fresh whole fish, fillets, and frozen fish, as you may be purchasing non-kosher fish or contaminating it with residue left on knives and cutting boards. Fried fish fingers involve three issues: the fish, the oil, and the frying equipment (often used for both kosher and non-kosher fish). Smoked fish is typically brined and then smoked along with non-kosher fish. According to Jewish law, the brining and smoking process is equivalent to grilling over a fire, making the product non-kosher. Smoked fish is often coated with oil, which may not be kosher. Although herring is a well-known kosher food, it is not always kosher. The preparation of herring can raise numerous kosher issues, such as mono- and diglycerides, non-kosher vinegar or wine, sour cream, breadcrumbs, spices, and contaminated equipment. The above list of kosher and non-kosher fish is provided by Dr. James W. Atz, Curator of the Department of Ichthyology and Director of Bibliography at the American Museum of Natural History in New York. We would also like to thank Rabbi Jena and the Union of Orthodox Jewish Congregations of America for permission to reprint this information.