Tracking Corn, From The Silo To The Taco Shell

Genetically modified foods are very hard to track. Last month, for example, Kraft Foods Inc. voluntarily recalled millions of its Taco Bell-brand taco shells after so-called GM corn, grown for animal feed but not approved for human consumption, became mixed into the shells during production. Now, researchers at Purdue University in West Lafayette, Ind., and the Indiana Crop Improvement Assn. say they have developed a software program that translates the GM-content of crop seed into computer code. With this, the purity content can be tracked as farmers harvest, store, and sell their grain.

If different strains are mixed in a silo bin--including some that are gene-modified--the program can calculate the overall purity before the grains are shipped to the next destination. "We keep going on and on like that until it gets to the end user. That way we can make sure nothing is contaminated," says Richard A. Vierling, a Purdue agronomy professor and genetics lab director with the crop association.

The strain-tracking software program should be available in December.