Two AOAC-approved tests for gluten
I recently read on the Internet the article “Testing for Gluten in Foods” in the February 2011 issue of Food Technology. It said that “AOAC International has approved the method ‘Gliadin as a Measure of Gluten in Foods’ as Official Method 991.19. This ELISA uses the R5 monoclonal antibody, which binds to gliadin/gluten and similar prolamins from related grains. AOAC’s Research Institute, which provides an independent evaluation of test kits, has certified R-Biopharm’s RidaScreen® Gliadin method as a Performance Tested Method. The test uses the R5 monoclonal antibody, which is recommended by the Codex Alimentarius.”

I would like to point out that AOAC Official Method 991.19 is using not the R5 antibody but the Skerritt Antibody. Note that there are now two AOAC Official methods for gluten: In 1991 AOAC International approved the Skerritt Method as Official Method 991.19. However, this Gluten ELISA is intended to be used for the detection of gluten at levels >200 ppm. The newly approved AOAC Official Method 2012.01 using Ridascreen Gliadin has a limit of detection of 3 ppm gluten. It uses the Codex Alimentarius recommended R5 gliadin antibody, which is generally accepted as the standard method for the detection of gluten in foods.

—Stella Lindeke, Product Manager, Allergens, R-Biopharm AG, Darmstadt, Germany