Traditional Jewish practice forbids the consumption of some types of food (certain varieties of animals, animals slaughtered by any but the accepted method, the blood of mammals or birds) and some combinations of foods (roughly, meat with milk products). It mandates kitchen practices that help maintain those restrictions. These laws, known collectively as kashrut (literally, “fitness”), are observed in varying degrees among Jewish families and individuals. For those who choose to observe some or all of the system of kashrut, it serves as a frequent reminder of their distinct identity as Jews.
Many explanations have been offered for each aspect of kashrut. The Torah suggests that the Israelites attain unique holiness through food restrictions that distinguish them from other peoples. Some later explanations are framed in behavioral categories internal to Judaism, such as inculcating kindness and preventing cruelty to animals. Others are the insights of historians and anthropologists, frequently on the basis of comparison with other religious systems. None has proved universally satisfactory, but many have served to bolster the desire of some Jews to observe these challenging restrictions.
The Torah is the source of limitations on what foods from animal sources may be consumed and of the ban on “cooking a kid in its mother’s milk.” Rabbinic tradition interprets those prohibitions, filling in operative details and setting up further restrictions to provide greater assurance that the Torah’s bans are not violated. Over centuries of application and interpretation, these restrictions
have been extended and refined. Modern Jewish thinkers and movements vary in the degree to which they advocate the observance of kashrut. Some have tried to blend it with such contemporary concerns as vegetarianism and environmentalism.
Food from animal sources is subject to many conditions. Only certain species of mammals and birds are kosher, and then only if slaughtered in a particular fashion and found healthy upon inspection. The prohibition on consuming blood requires that meat be salted and soaked. Fish with fins and scales are kosher, and their flesh requires no such special treatment.
Today, Jews who observe kashrut rely on recognized supervision agencies whose symbols on packaged foods or whose certificates in shops and restaurants testify to the acceptability of the food within.
Preventing the mixing of meat products and milk products has led to the practice of maintaining separate sets of cookware, tableware, and flatware for meat and dairy. Some households also have items used for neither meat nor milk (this category is called pareve, or neutral); food prepared using these can be eaten with either meat or dairy.
Establishing a kosher kitchen requires some work, but the regularities are not difficult to maintain. Making an existing kitchen kosher may involve replacing some equipment, but many items can be made kosher and some need no treatment at all. With good will, flexibility, and creativity, individuals can “keep kosher” in nonkosher homes and restaurants.