What makes some foods kosher and others not? What food preparation methods are necessary to keep food kosher? What is parve? These and other commonly asked questions are answered in the following article authored by Rabbi Joshua Mark, Jerusalem, Israel.

Kosher refers to a set of biblical rules regarding food and food preparation. When food is prepared according to these rules it is deemed kosher. Those who take special care to eat such foods are considered to be ‘kosher'.

As put forth in the Bible, there are rules for determining the foods that can be eaten and those that should be avoided. For instance, when it comes to consuming meat we are told that we may eat only of those species that chew their cud and have split hooves. We are also told how meat is to be slaughtered and how it must be drained of blood.

Fowl and fish are also included in kosher rules. The bible lists about twenty different species of birds that cannot be eaten. Not included in that list is chicken and turkey. Only fish that have fins and scales may be eaten. That excludes many of the most popular shellfish such as lobster, shrimp, and clams. On the upside, salmon, pike, and whitefish are kosher so you can enjoy Sunday brunch with lox and other traditional fish delicacies.

Even when the food itself is kosher, there are limits on how we prepare what we eat. This most often involves avoiding cooking meat together with dairy products. That is the reason that kosher eaters cannot eat cheese burgers or chicken parmesan. In fact, kosher eaters cannot even eat meats served on plates that were used for dairy or vice versa. Meat or dairy may only be prepared with it's own type or with neutral foods (containing neither meat nor dairy products), otherwise known as parve foods. Examples of parve foods include vegetables, grains, fruits and certain baked goods .

Less well known is the prohibition of preparing kosher food together with non-kosher food. That's why most kosher consumers eat in restaurants that serve only kosher food. And when food is prepared and packaged elsewhere such as done with almost all of the food we find in stores, kosher consumers insist on certification that the food was prepared according to these biblical laws.

In the last forty years the number of kosher consumers has exploded. In order to meet the needs of these consumers, a number of organizations certify the kosher status of commercially sold food. This is called kosher supervision. Today, there are over one hundred different organizations that offer kosher supervision. Most of them have trademarked emblems and symbols that can be easily found on the food items that are certified kosher. The most well known kosher symbol is the O-U, the trademark of the Union of Orthodox Jewish Congregations of America.