I am doing a lot of research about food fortification: Corn, Sorghum and Soybeans plus other things to make a porridge flour for children, lactating mothers and adults.
Look the information in the web pag of Worl Food Programme. This organization have a porrige named CSB (Corn and Soya Blend) for children of the developing countries
The most controversial mineral in infant formula is iron. The American Pediatric Association also published a position statement about formula fortification:
There are peer-reviewed research articles that address mineral absorption and iron supplementation. Here is one: http://www.ncbi.nlm.nih.gov/pubmed/3761108