Levels of proteinaceous material in beer in relation to celiac problems

LINDSAY J. GUERDRUM (1), Charles W. Bamforth (1)
(1) Department of Food Science and Technology, University of California, Davis, CA

About 1% of the Western population suffers from celiac disease, making it one of the largest food sensitivities in the world. celiac disease is an inherited immune-mediated enteropathy that damages the small intestine, thereby interfering with nutrient absorption upon consumption of gluten. Patients with celiac disease must abide by a strict gluten-free diet void of wheat, rye, barley, and possibly oats. Clinical sensitivity toward gluten differs considerably among patients but the current Codex Alimentarius standard for a food to be labeled as gluten-free is no more than 20 ppm gluten. As most beers are brewed from barley- or wheat-based grists, it has long been inferred that they are not suitable for people suffering from Celiac disease. However the veracity of this conclusion has been questioned, bearing in mind the considerable amount of protein modification and removal that occurs during malting and brewing. Review of the available methodology concluded that the most reliable procedure that ensures quantification of all the relevant proteinaceous material (including degradation products) is the so-called competitive R5 ELISA method. This method was used to assess the levels of gliadin in commercially available beers spanning the range of grist material. Gliadin levels ranged from <3 mg/L for gluten-free beers to 145.8 mg/L for filtered American pale wheat beers. With regards to the Codex Alimentarius standard, 10 of the 28 beers tested were within the guidelines. Many well-known brands in the United States have very low levels of detectable gliadin. The key brewing factors that impact gliadin levels are presented.

Lindsay Guerdrum received a B.S. degree in biochemistry from the University of New Mexico in Albuquerque. She is currently in her second year as a food science and technology master’s student at the University of California, Davis. During the summer of 2010 she worked as an intern for Anheuser-Busch InBev in Fairfield, CA.