For millennia, Judaism has observed traditional religious dietary laws known in Hebrew as «kashrut». These laws define the preparation and consumption of foods and drinks. Simply put, foods are divided into two categories: permitted or «kosher», and forbidden or «non-kosher» or «treife». There are major differences in the degree of observance of kashrut, and it varies according to religious denomination. Jews who adhere strictly to religious laws closely follow the regulations, while secular Jews conform only partially or not at all.
Wine, grape juice and certain spirits are only deemed kosher if the bottle displays a kosher certification. According to certain interpretations of the dietary laws, milk is only defined as kosher if the milking and bottling is supervised by Jews. Water is kosher, as are numerous soft drinks, if they are tested for kosher production, such as Coca-Cola and Red Bull
Special regulations apply in the dietary laws governing meat. The consumption of meat is only permitted if it originates from animals which are ruminants and have cloven hooves, such as beef or lamb, or from poultry. Meats that are excluded include pork and horse-meat. Mammals and poultry must be slaughtered and processed under specific conditions. This ritual slaughter is known as «shechita». Fish are kosher, provided they have fins and scales. Eating shellfish or fish without scales or fins, such as prawns, squid or mussels, is forbidden.
Separation of meat and milk
A further characteristic of the dietary laws is the strict separation of meat and dairy products. For this reason, kitchens must separate plates and cooking utensils, i. e. plates, cutlery, pots and pans or sponges, into the categories «meaty» and «milky». Meat and dairy products may only be cooked separately and cannot be eaten together. After consuming meat products, an interval of several hours must be observed before eating dairy products
Kosher kitchen and koshering
Jews who are strictly religious and rigorously observe the dietary laws, are restricted to eating only in kosher restaurants or a kosher kitchen at home. Before a kitchen can be used for the first time, it has to be made kosher, known as «koshering». This includes, for example, the heating of hotplates to remove any food residues, or the strict division of the kitchen into «fleshy» and «milky». In third-party kitchens, such as in rented apartments, the hotplates are often covered with special aluminium foil or brought along special hotplates are used. It can be very complicated for restaurants or hotels to expand their services to include a kosher menu, and is only possible by complying with all the regulations and then receiving a kosher certification. That is why this service is generally restricted to specialist restaurants with a kosher kitchen.
When buying kosher food, the so-called kosher lists offer help. The kosher lists are maintained and published by the individual Jewish communities in Switzerland. The Community of Interest for Kosher Foodstuffs (IGFKL) supports the rabbis of the communities. The IGFKL controls the foodstuffs, makes the necessary enquiries with the producers and makes this information available to the rabbis for the preparation of their kosher lists. The kosher lists catalogue the kosher products available in Swiss supermarkets. Fruit, vegetables, eggs and grains are all classified as kosher. All other foods are checked for their ingredients and included in the kosher lists. Even a small amount of non-kosher ingredients will make a product non-kosher. Some towns and villages have special butchers for kosher meat and kosher supermarkets or a «kosher department» in the supermarket.