Gluten-Free Update: What Food Processors Need to Know about Gluten-Containing Products
When the food label reads “gluten-free,” consumers expect that their food purchase will be safe to eat, especially if they have celiac disease, non-celiac gluten sensitivity or a wheat allergy. But an increasing number of studies, like the one in the Journal of Pediatric Gastroenterology and Nutrition,[1] report that mucosal recovery is lacking in 20 percent of the children diagnosed with celiac disease despite maintaining a gluten-free diet. Numerous patients in my practice with gastrointestinal disorders who were prescribed a gluten-free diet are complaining that the dietary change has made an insignificant difference in their symptoms.
What is Gluten-Free?
Gluten is a mixture of proteins (prolamins, gliadins, glutelins, glutenins) in wheat, barley, rye and possibly oats from cross-contamination. The U.S. Department of Agriculture (USDA) and United Nations Foods and Agricultural Organization have set the maximum limit for gluten in products labeled as gluten-free at 20 mg gluten/kg.[2] According to USDA data cited in Food Safety Magazine,[3] the top allergen recalls for 2015 were milk/dairy, peanuts, eggs and wheat/gluten.
An enzyme-linked immunosorbent assay (ELISA) is used to measure the amount of gluten and gliadins in foods but is less reliable for glutenins.[4] Many companies label products gluten-free and state “guaranteed to be gluten-free” based on the ELISA results, despite inadequate testing for all gluten-containing proteins. ELISA testing can only evaluate the alcohol-soluble gliadin but does not effectively assess the alcohol-insoluble glutenin fraction that can result in malabsorption symptoms occurring despite a gluten-sensitive patient following a gluten-free diet.