Study on the reduction of acrylamide in mixed rye bread by fermentation with bacteriocin-like inhibitory substances producing lactic acid bacteria in combination with Aspergillus niger glucoamylase

This study mainly focuses on a strategy for reducing of acrylamide in cereal products, predominantly in bakery products. The effect of mesophilic lactic acid bacteria (LAB) strains as well as a novel fermentation media on the bases of extruded rye wholemeal on the acrylamide formation in mixed rye bread of different weight of loaf was studied. The LC MS/MS method for acrylamide determination in bread crumb has been applied. Addition of 15% low pH (pH 3.4-4.3) fermented product to bread dough, which were produced by using commercial strain Lactobacillus casei and bacteriocin-like inhibitory substances (BLIS) producing strains Lactobacillus sakei KTU05-6, Pediococcus acidilactici KTU05-7 and Pediococcus pentosaceus KTU05-8 separately, caused significant reduction of acrylamide in mixed rye bread. All bread loafs of 1000 g contained less by 27% acrylamide concentrations versus loafs of 500 g. Acrylamide formation was affected (r(2) = 0.7193) by total reducing sugar content in bread and slightly correlated (r(2) = 0.5587) with reducing sugar content in sourdough. The treatment of extruded rye wholemeal with Aspergillus niger glucoamylase as compared to the control sample was found to have a positive effect on the acidification process lowering the acrylamide formation on an average by 59.4% and 40% in 500 g and 1000 g loafs of bread, respectively. This study demonstrates that acrylamide content could be reduced by using LAB excreting lower amylolytic activity in the medium, while the higher proteolytic activity is preferred. (C) 2012 Elsevier Ltd. All rights reserved.