The below mentioned text does not makes any claim to to be complete, but instead, it gives further insight into the subject matter.

 „Kosher“ Foods and the „Jewish Food Laws‘‘

In contrast to vegetarian food, a religious background is clearly hidden behind the Kosher food standards. In statutory regulations of Jewish religious law, determined in the Thora; all foods are divided into ‚Kosher‘ and ‚Non-Kosher‘, wherein „Kosher“ is permitted in accordance with the Jewish Food Law.

There are 4 basic rules, which decide on whether a foodstuff is Kosher or not Kosher!

These include, the difference of permitted and not permitted animals, prohibition from consuming blood, segregation of „meaty“ (Hebrew: basari) and „dairy“ (Hebrew: chalawi) as well as the „neutral“ foodstuffs.
These divisions are established on the basis of avoiding accompanying physical and moral damage.

The Kosher animals are those, who have two column hooves and are ruminants, such as cows, goats and sheep. Pigs, horses, rabbits and camels do not belong to this category since they are neither ruminant nor do they have two column hooves. Both the attributes must be existent. These animals are thus prohibited.

Moreover, Kosher meat must be prepared in a special manner. It must be derived from only Kosher animals that had been slaughtered using Kosher methods. This means, based on the prohibition on consumption of blood, the blood of the animal must be completely drained out after slaughtering so that no blood is contained in the flesh. In addition to this, the Kosher meat is soaked in water, salted and rinsed before it is further used. Background: The blood is the centre of the soul, therefore it must not be shed nor consumed.
In contrast, all those Fish and water animals are Kosher, who have Fins and Scales, such as Salmon, Trout and Tuna fish. According to this, eels, Catfish, Lobsters, Mussels and Squids are not permitted, since they are either neither fish or nor have scales and fins. Fish must not be slaughtered as per the ritual guidelines, since they are considered neutral (see below).
With poultry, only those are considered Kosher, which are slaughtered according to the Jewish rituals and belong to domestic poultry, such as: Chicken, Duck, Goose and Pigeons.

Products, manufactured from Kosher foods are also mostly Kosher, such as milk and milk products. Milk from Kosher animals, such as cow milk, goat’s milk and sheep’s milk is allowed, but horse’s milk and camel milk is not. Products, which are obtained from Kosher milk, such as cream, butter, yogurt and cheese are Kosher, provided no animal rennin or other animal products are added.
Another law states that meaty food, which consists of meat and such products that contain meat as an ingredient, are not to be consumed simultaneously not with milk containing foodstuffs, that have milk and products as ingredients. Depending on the composition, a few hours of break must be given between a fleshy and dairy food product. With a strict formal interpretation, even separate dishes, cutlery, etc. are to be used, so that the meaty and dairy food products do not come in contact with each other.
There is also a so-called „neutral“ (Parve) food which consists of fruits, vegetables, cereals, eggs, honey and fish. Neutral foods may be consumed with fleshy as well as with dairy foods.

How is a Kosher product obtained?

Before rolling out a Kosher product, it must be certified by a Rabbi. For this purpose, other ingredients can be found in the product and these ingredients must also be Kosher-certified. A Rabbi visits the production site and checks whether everything is functioning as Kosher.  In addition to this, even the strict classification in the production of non-Kosher products and Kosher products is also observed. For example, this is done by separating the place and by thorough cleaning. Depending on the sensitivity of the product, such as cheese and wine, usually a Rabbi or an authorized Jew is present at the production site so that the respective product may be rewarded as Kosher. If a Rabbi is present during the entire production, including the packing, then the product may be labeled with the „Badaz - Quality“ (Super Kosher – Mehdarin).  

As soon as a Kosher certificate is obtained for the product, it can be provided with the Kosher Logo (usually a U with a circle). In our degree of latitude, this is however less common, but several lists of Kosher products are published on the respective homepages or in product databases.