There are a number of different requirements that must be met in order to earn kosher certification. Some of these requirements include:
The food must be made from ingredients that are themselves kosher. This means that the food cannot contain any non-kosher items, such as pork or shellfish.
The food must be prepared in a clean and sanitary environment.
The food must be cooked in accordance with Jewish law. For example, meat and dairy products cannot be cooked or eaten together.
Certain animals must be slaughtered in a specific way in order to be considered kosher.
Certain foods, such as pork and shellfish, are never considered kosher, no matter how they are prepared.