Gluten-free barley malt beers

Gluten and toxic gluten peptides, current situation in Belgian barley malt beers and technology for the production of gluten-free barley malt beers. Malting and brewing processes remove much of the proteins in the traditional grist to generate amino acids for yeast metabolism and to minimize the risks of colloidal instability of the beer. The question is whether gluten and the relevant celiac-inducing peptide sequences of hordein can be sufficiently eliminated to obtain gluten-free beers (<20 ppm gluten) according Directive EC 828/2014. The test kits used for the gluten and celiac-toxic peptide analysis are Sandwich ELISA-RIDASCREEN Gliadin for gluten analysis (R7001) and Competitive ELISA-RIDASCREEN Gliadin for celiac-toxic peptide analysis (R7011 and/or R7021). The standards for the gluten estimation are Prolamin Working Group (PWG) reference material. The gluten content of the examined malt beers (2015) ranges between beneath the quantitative detection limit (<5 ppm) to >80 ppm gluten proteins as determined with the Sandwich ELISA-Ridascreen Gliadin kit. 63 of the 70 examined beers (90%) can be considered gluten-free (<20 ppm gluten). This corresponds with 30 different breweries producing these beers. When using the Competitive ELISA-Ridascreen Gliadin kits only a small part of these U+2018gluten-freeU+2019 beers will still be gluten-free as the Competitive ELISA kit analyzes for the toxic gluten peptides (respectively 23 out of 70 beers, 34%). Lab scale brewing experiments (60 Liter pilot brewery) and industrial brewing case studies (20 and 30 Hectoliter) were performed to test the effect of different processing steps. The lab scale brewing experiments revealed that the gluten content in the final beer can clearly be diminished by either using prolyl endopeptidase (PEP) and/or tannic acids during the brewing processes. Even 100% barley malt beers final gluten and toxic gluten peptides contents were lower than the threshold for food products to be declared U+2018gluten-freeU+2019 (20 ppm). These results could be confirmed on an industrial scale, resulting in the production of a gluten-free 100% barley malt beer (< 5 ppm gluten proteins). Meura filtration on the other hand showed to be insufficient to produce gluten-free beer. Additional research is being performed to reveal the effect of other process steps.