Impact of barley selection and mashing profile on the arabinoxylan content and structure in beer

Non-alcoholic and low-alcoholic beers often suffer from inferior foaming quality and lack palate fullness, both of which are positively influenced by arabinoxylan. This study aimed to identify factors during brewing that most affect arabinoxylan content and structure. Analysis showed that malting and mashing had the most significant impact on arabinoxylan, increasing its extractability and reducing its molecular weight. Given that arabinoxylan was most affected at the initial stages of brewing, barley malt selection and mashing profile adjustments were further investigated. Barleys (n = 21) were micro-malted, exhibiting a wide range of endoxylanase activity (6-63 U/kg dm malt) and water-extractable arabinoxylan content (0.54 %-1.04 % dm malt). Malts with extreme values for these parameters were subjected to two mashing profiles, with only one allowing endoxylanase activity, to evaluate the impact of both barley selection and endoxylanase activity on the arabinoxylan profile in beer. The resulting beers had total arabinoxylan content ranging from 1.0 to 2.0 g/L and high-molecular-weight arabinoxylan from 0.4 to 1.2 g/L, levels that significantly contribute to palate fullness and foam stability. The negligible impact of endoxylanase activity highlighted the importance of barley selection. Therefore, brewers should make informed barley (malt) choices to optimize arabinoxylan content and structure in beer.