Delivery system of vitamin B₁₂ in plant-based food products from Propionibacterium freudenreichii subsp. shermanii ATCC 13673 grown in agro-industrial by-products

Plant-based diets are emerging worldwide, potentially exposing an increasing number of people to vitamin B₁₂ deficiency. In this study, we investigated the application of P. shermanii ATCC 13673 spray-dried biomass as a source of vitamin B₁₂ to fortify a plant-based food, in this case, bread. Vitamin B₁₂ characterization by LC-MS/MS system, bread fortification, and biocompatibility assays were performed. Vitamin B₁₂ in P. shermanii ATCC 13673 spray-dried biomass samples (up to 18 μg/g) was found mainly in the hydroxycobalamin form. Bread samples fortified with P. shermanii ATCC 13673 spray-dried biomass retained two-thirds of vitamin B₁₂ after baking. Additionally, the vitamin B₁₂ was as bioaccessible as the cyanocobalamin commercial standard, which was added to control fortified breads. Moreover, biocompatibility assays (cytotoxicity and monolayer integrity) showed that bread samples fortified with P. shermanii ATCC 13673 spray-dried biomass did not damage Caco-2 cells, indicating its potential as a source of alternative, safe, and available vitamin B₁₂ in plant-based foods.