European Brewery Convention Congress (EBC) edition:34 location:Luxembourg date:26-31 May 2013
The presence of microorganisms producing cell wall hydrolysing enzymes such as xylanases during malting can improve mash filtration behaviour and consequently have potential for more efficient wort production and enhanced beer flavour quality and stability. Therefore, arabinoxylan-degrading bacteria occurring on the grains during malting were isolated, screened for xylanase activity, and identified by 16S rRNA gene sequencing. In this way, xylanolytic bacteria such as Sphingobacterium multivorum, Stenotrophomonas maltophilia and Aeromonas salmonicida were identified. In addition, as especially microbial xylanases belonging to the glycosyl hydrolase (GH) family 10 are highly interesting for malting process optimisation, we also assessed the diversity and distribution of these xylanase genes by 454 pyrosequencing during malting, i.e. from barley up to kilned malt. Results provide a deep insight into the occurrence and diversity of xylanase sequences of microbial origin during malting.