The high phytate content of soybean meal requires supplementation with inorganic sources of phosphorus in monogastric animals. Dietary P in excess of animal requirements is excreted into the environment and becomes an environmental pollutant (Dilger et al., 2006).
The high digestibility of the amino acids of soybean meal in diets for monogastrics and the high content of lysine allow the formulation of diets that contain less total protein than with other protein sources and less excess nitrogen in the feed, thereby reducing nitrogen excretion into the biosphere (Pettigrew et al., 2008).
Soybean meals are usually extracted with hexane, a solvent that is extremely flammable and non-biorenewable, poses health risks and is regulated as a hazardous air pollutant (O'Quinn et al., 1997).