Effect of lactic fermentation on nutritional potential of multigrain flours based on wheat, rye and oat

Abstract

This study was focused on the multigrain flours obtained by milling blends with various amounts of wheat, rye and hulled oat, and on the sourdoughs prepared out of these flours using different commercial starter culture. The folate and total phenol levels and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity (DPPH-RSA) of multigrain flours increased with the addition level of rye and
hulled oat. Among the fractions obtained through milling, higher levels of folates were registered in brans, followed by shorts and then by flours. The folate contents in brans and shorts were about of 1-1.4 times higher than in the flours. The sourdough fermentation realized with different commercial starter cultures induced the increase of the total phenols content and DPPH-RSA. The highest levels of folates were obtained when fermenting the flour suspensions with Lactobacillus delbrueckii subsp. Bulgaricus and Streptococcus thermophilus, followed by samples with Lactococcus lactis subsp. Lactis and Leuconostoc. The sourdough fermented with Lactobacillus rhamnosus, Lactobacillus brevis and Lactobacillus plantarum had lower folate contents compared to the corresponding controls obtained through spontaneous fermentation. The obtained results suggest that both the type of cereals used to obtain the flours and the starter culture used to
prepare the sourdoughs are suitable tools which worth be used for modulating the nutritional profile of the baking products.