Melamine-Tainted Wheat Gluten, Rice Contained Wheat Flour

An official with the U.S. Food and Drug Administration Tuesday said the investigation into melamine-tainted feed
ingredients wheat gluten and rice protein concentrate were misrepresented by the Chinese companies and contained wheat flour. 
 
David Acheson, chief medical officer, Center for Food Safety and Applied Nutrition, FDA, told reporters on a conference call that the FDA's investigators found that the wheat flour in the products was determined to be
the source of the melamine. He also said wheat gluten is a high-protein component of wheat flour. 
 
Visual microscopy and starch tests were used in determining that the material was indeed wheat flour. Acheson said the focus is still on wheat gluten and rice concentrates but he wouldn't exclude the possibility of testing wheat flour imports as well. 
 
The two Chinese companies being investigated from the original finding in April misrepresented the wheat gluten and rice protein concentrate since it contained wheat flour, he said. This discovery doesn't mean this is a new batch of material being investigated, he added, it is just more information now known about the original materials. 
 
The investigation originally sprang from pet food that contained supplements tainted with melamine in China and then exported to the U.S. Melamine can make supplements appear to have falsely higher protein levels, which commands a higher price for the producer.