According to Jewish dietary laws, “kosher” means “fit to eat.” However, to be kosher, food also must be prepared in a kosher way and served with kosher utensils. Food that is not “fit to eat,” or is not prepared following the kosher rules or served using kosher utensils, is known as non-kosher or "tref." Kosher is also used to describe ritual objects which are made in accordance with Jewish laws.
To be considered kosher, an animal must have cloven hooves and chew its own cud. Cows, sheep and goat possess both of these qualities and are undoubtedly kosher. On the other hand, pigs and hares lack one of these qualities and are, therefore, considered non-kosher. Sea animals must have fins and scales to be kosher. Tuna, salmon and herring are kosher, but lobsters, oysters and crabs are not. Chicken, geese and ducks are also permitted. A kosher animal died of natural causes or killed by another animal may not be eaten. Only a kosher animal that had no disease or flaws at the time of slaughter and is properly drained of blood (which is also important) is fit to eat. An animal that is kosher, if not slaughtered in accordance with Jewish laws, becomes non-kosher.
Fruits and Vegetables
Fruits and vegetables are generally considered kosher. However, they always must be carefully cleaned and examined for bugs and worms which are not kosher. This particularly applies to leafy and flowery vegetables which can hide small, hardly-visible bugs. Whole grapes are kosher, but grape products such as wine or grape juice are kosher only if produced by Jews. This is because wine is commonly used in rituals.
Dairy products are kosher if they come from an animal that is kosher. Another important fact about dairy is that it should never be eaten with meat. Moreover, dairy and meat should be prepared in separate pots, served on separate plates and eaten with separate cutlery, because kosher status can be transmitted from the food to the utensils and vice versa.
When buying processed food, it is difficult to know all the ingredients contained therein and the way they are processed. Kosher-packaged food is labeled with a symbol that certifies the processing meets the standards of Jewish dietary laws. Certification involves inspecting the ingredients, examining the food preparation process and inspecting the processing facilities to ensure kosher standards are maintained.