"Foreign material" in bulk solid samples refers to materials that do not belong to the expected composition of the bulk solid. These could be elements such as stones, metal particles, glass, plastic, or other contaminants that can enter the bulk solid through the manufacturing process, packaging, transportation, or storage.
Identifying foreign material in bulk solid samples is essential to ensure product quality and minimize potential risks. This is particularly important in industries like food and feed manufacturing, where foreign material can pose a health hazard to humans or animals. In other industries, such as the construction sector, foreign material can also adversely affect the quality of the end product.
Methods for detecting foreign material can include visual inspection, sieve analysis, magnetic testing (for metallic contaminants), or even specialized technologies such as X-ray or infrared technology. The methods of detection depend on the type of bulk solid and the expected contaminants.