70. An investigation of process controls and microbes for the degradation of gluten proteins in wort

Brett Taubman (1), Travis Laws (1); (1) Appalachian State University, Boone, NC, U.S.A.

Technical Session 20: Mashing, Boiling, & Wort
Wednesday, August 17  •  8:15–9:30 a.m.
Plaza Building, Concourse Level, Governor’s Square 14

Gluten, a storage protein found in many cereal grains, is most notably known for the adverse effects it causes some people, such as those who suffer from celiac disease. As a result, those who wish to drink malt beverages, but have a gluten intolerance, have to resort to drinking gluten-free alternatives, which often have off-putting tastes from non-traditional, gluten-free grains used in the brewing process. One potential solution to this issue may lie in a category of beers that have gained in popularity recently. Sour beers contain a mixture of yeast as well as different bacteria that may hydrolyze gluten-type proteins to small enough oligopeptides or single amino acid units, thereby not causing an immune response in people with celiac disease. Lactobacillus brevis, Lactobacillus curvatus, Lactobacillus plantarum, and Pediococcus pentosaceus were selected for laboratory fermentations based on their ability to use gluten as a nitrogen source for growth. Laboratory fermentations of all-barley beers were analyzed using the Ridascreen gliadin competitive enzyme immunoassay. Results from the beer samples taken 14 days after inoculation show that the bacteria were successful in lowering the gluten concentration, with all samples measuring below the FDA mandated limit of 20 ppm. A second laboratory fermentation with a high percentage of wheat malt also indicated that the bacteria were successful in significantly lowering the gluten concentrations of the final products. Other parameters in the mash process, such as mash temperature, pH, thickness, and malt content, are being examined to determine how gluten concentrations are affected before fermentation. Initial results indicate that higher mash temperatures result in higher concentrations of gluten in the resulting wort, whereas decreases in the pH of the mash decrease the concentration of gluten in the wort. Additional research is being conducted to determine the effects of mash thickness on gluten concentrations.

Brett Taubman is a faculty member of the A.R. Smith Department of Chemistry at Appalachian State University engaged in instruction and academic research within the chemistry and fermentation sciences. He has earned B.S. degrees in both finance and chemistry from the Pennsylvania State University and Montana State University, respectively, and a Ph.D. degree in analytical and environmental chemistry from the University of Maryland in 2004. Following his graduate studies, he worked as a postdoctoral research associate at the Pennsylvania State University before joining the chemistry faculty at Appalachian in 2007. Brett has successfully developed a pilot instructional brewing facility on the ASU campus and currently serves as president of Ivory Tower, Inc., a 501(c)(3) non-profit corporation with the mission of supporting research and education within fermentation sciences. He helped to develop the four-year degree program in fermentation sciences and shares time between that program and the Department of Chemistry. He has been brewing and teaching brewing science and technology for over 10 years and is a member of the American Chemical Society, the American Society of Brewing Chemists, Master Brewers Association of the Americas, and the Institute of Brewing and Distilling.