Production and application of barley malt extract with high peptidase activity for the degradation of gluten in wort
- 499 Downloads
Special malt with high gluten-specific peptidase activity was prepared by germinating barley grain for 8 days at 18 °C and 48 % humidity. Endogenous malt peptidases were characterized and used to degrade gluten in barley wort. Peptidases of aqueous malt extracts degraded celiac-active peptides by cleaving peptide bonds involving proline residues. The peptidase activity was not affected by cultivar, area of cultivation, and high temperatures up to 80 °C during kiln drying. Temperatures up to 50 °C were tolerated without loss of full activity in aqueous solution. The presence of ethanol decreased the activity significantly. Cross-flow filtration, freeze-drying, and evaporation under reduced pressure at 50 °C were used to produce a concentrated enzyme-active malt extract. The latter method yielded the best results, and the obtained concentrate was used to study gluten degradation in barley wort as affected by concentration of the extract, incubation time, and temperature. The gluten content was determined by a competitive R5-ELISA. The addition of 10 % concentrated extract (grist-to-water ratio 1:2.5; 40.4 °Brix) to wort and incubation for 24 h at 50 °C resulted in a gluten-free wort.
KeywordsCeliac disease Gluten Peptidase Barley Malt extract Beer
This research project was supported by the German Ministry of Economics and Technology (via AiF) and the FEI (Forschungskreis der Ernährungsindustrie e.V., Bonn), project number AiF 16791N. The authors would furthermore like to thank Florian Gschwendtner for excellent assistance and Dr. Jean Titze from Doehler Group for providing the facilities and knowledge for the upscale.
Compliance with ethical statements
Conflict of interest
Compliance with ethics requirements
This article does not contain any studies with human or animal subjects.
- 1.Maiuri L, Troncone R, Mayer M, Coletta S, Picarelli A, de Vincenzi M, Pavone V, Auricchio S (1996) In vitro activities of A-gliadin related synthetic peptides. Damaging effect on the atrophic coeliac mucosa and activation of mucosal immune response in treated coeliac mucosa. Scand J Gastroenterol 31:247–253CrossRefGoogle Scholar
- 4.Codex standard for foods for special dietary use for persons intolerant to gluten. Codex Alimentarius, International food standards. CODEX STAN 118-1979, adopted in 1979; amended 1983; revised 2008. Rome, ItalyGoogle Scholar
- 10.Kerpes R, Knorr V, Procopio S, Koehler P, Becker T (2015) Gluten-specific peptidase activity of barley as affected by malting and its impact on gluten degradation. J Cereal Sci (submitted) Google Scholar
- 11.MEBAK (2006) Mitteleuropäische Brautechnische Analysenkommission. Collection of brewing analysis methods of the Mitteleuropäische Brautechnische Analysenkommission (MEBAK). Barley, adjuncts, malt, hops and hop products. MEBAK, Freising, GermanyGoogle Scholar
- 15.de Ritis G, Auricchio S, Jones HW, Lew EJ-L, Bernardin JE, Kasarda DD (1988) In-vitro (organ culture) studies of the activity of specific A-gliadin peptides in celiac disease. Gastroenterology 94:41–49Google Scholar
- 16.Wieser H, Belitz H-D, Ashkenazi A (1984) Amino-acid sequence of the coeliac active gliadin peptide B 3142. Eur Food Res Technol 179:371–376Google Scholar
- 18.Wieser H, Belitz H-D, Idar D, Ashkenazi A (1986) Coeliac activity of the gliadin peptides CT-1 and CT-2. Eur Food Res Technol 182:115–117Google Scholar
- 23.Arentz-Hansen H, Körner R, Molberg O, Quarsten H, Vader W, Kooy YM, Lundin KE, Koning F, Roepstorff P, Sollid LM, McAdam SN (2000) The intestinal T cell response to gliadin in adult celiac disease is focused on a single deamidated glutamine targeted by tissue transglutaminase. J Exp Med 191:603–612CrossRefGoogle Scholar
- 27.Tye-Din JA, Stewart JA, Dromey JA, Beissbarth T, van Heel DA, Tatham A, Henderson K, Mannering SI, Gianfrani C, Jewell DP, Hill AV, McCluskey J, Rossjohn J, Anderson RP (2010) Comprehensive, quantitative mapping of T cell epitopes in gluten in celiac disease. Sci Transl Med 2:41–51CrossRefGoogle Scholar