In accordance with 21CFR110 good manufacturing policy (GMP), every food manufacturer or processor must establish and enforce regulations and policies that preclude any foreign object, including glass, plastic, metal, or wood, from contaminating or adulterating any product. Of these four contaminants, the easiest with which to deal is metal. Due to the nature of its properties, the technology to detect metal in the product stream, a metal detector, is readily available. This is not the case for wood, plastic, or glass. These foreign substances are not readily detectable and the current x-ray technology is too expensive for most companies and is easily confused by matrix effects. It is thus incumbent on the company to take the necessary steps to prevent these materials from entering the food stream in the first place. These preventative measures take two avenues: up-front prevention and in-plant prevention.