1.2.1.1  Common adulterants in feeds

Adulteration is defined as the admixture of a pure substance with some cheaper and low quality substance. It is done intentionally usually to make money. In costly feed ingredients like oil seed cakes, adulteration is done by spraying urea in order to raise their protein content. However, sometimes brans are also added. Besides urea, oilseed cakes are adulterated with husk, non-edible oilseed cakes etc.

The common contaminant or adulterant is husk or sand (Table 1.2). Winnowing is the best method to detect husk in the feedstuffs. Sieving can be done to differentiate contaminants based on particle size.