Use of Weissella cibaria BAL3C-5 B2 to produce functional breads enriched in vitamin B₂ and fortified with dextran

Fermentation can improve the sensory, nutritional, and safety qualities of food. Furthermore, producing functional foods that contain bioactive compounds generated in situ by fermentative microorganisms is more sustainable than adding chemically or biotechnologically synthesized compounds.

Using optimized protocols for quantifying riboflavin (RF) and dextran, as well as gastrointestinal (GIDM) and colonic fermentation (CFDM) dynamic models, we have analyzed the functional properties of experimental breads (B_LAB) made from doughs inoculated with Weissella cibaria BAL3C-5 B2, a RF-overproducing spontaneous mutant of the dextran-producing lactic acid bacteria (LAB) W. cibaria BAL3C-5, which was isolated from rye sourdough.

Doughs made with binary (50:50) flour mixtures (wheat/chickpea, wheat/quinoa, wheat/teff, rice/quinoa and buckwheat/quinoa) were fermented with or without (control) W. cibaria BAL3C-5 B2. Dextran (~2% w/w) was only detected in the LAB-fermented doughs, which had 2-3-fold higher vitamin B₂ content. GIDM revealed that the bioaccessible vitamin B₂ content in wheat/chickpea B_LAB was ~3.7-fold higher than in control breads (B_C). Using CFDM, buckwheat/quinoa B_LAB and B_C were shown to significantly induce SCFA production by the gut microbiota, although B_LAB resulted in a greater increase (Lactobacillus and Bifidobacterium) or no decrease (Akkermansia) of the abundance of beneficial bacteria.