Biological acidification and beer quality: addition of lactic acid bacteria isolated from malt

Two lactic acid bacteria, Pediococcus acidilactici HW01 and Leuconostoc citreum isolated from Pilsner malt, were added during mashing and the impact on fermentation examined. The pH of lactic acid bacteria supplemented (bioacidified) wort and finished beer were lower than that of the control. Bioacidified worts resulted in higher levels of free amino nitrogen, reducing sugars and alcohol in the corresponding beers. Foam stability of beers from P. acidilactici and L. citreum worts were increased by 19% and 26%, respectively. The filtration time was reduced in P. acidilactici treated beers but increased with L. citreum. The use of P. acidilactici and L. citreum as bioacidification agents resulted in beers with higher sensory quality. (C) 2020 The Institute of Brewing & Distilling