Evaluation of Sensory and Physicochemical Characteristics of Vitamin B12 Enriched Whole-Meal Sourdough Bread Fermented with Propionibacterium freudenreichii

The sustainable production of vegan or vegetarian food rich in vitamin B-12 is a challenge. Propionibacterium freudenreichii fermentation has been identified as an effective method for the enhancement of vitamin B-12 content in foods. However, limited studies have been conducted on the co-fermentation of P. freudenreichii with other bacteria. This study investigated the co-fermentation of P. freudenreichii with Lactic acid Bacteria (LAB) and its effects on the sensory characteristics of whole-meal sourdough bread (WMSB) in comparison to WMSB produced with LAB alone. The effects of P. freudenreichii co-fermentation on WMSB vitamin B-12 content were also evaluated. Results indicated that P. freudenreichii co-fermentation with LAB significantly reduced (p < 0.05) crumb hardness when compared with WMSB produced with only LAB (4532 +/- 176 g and 5313 +/- 846 g respectively). A significantly higher adhesiveness (p < 0.05) was also observed due to the presence of P. freudenreichii. Triangle testing showed that perceptible differences were observed between the two WMSB types investigated in this study (p < 0.05). Qualitative data from focus group testing indicated that WMSB produced with co-fermentation has a more homogeneous texture. However, improvement in aroma, texture, and taste was possible in both bread types. The co-fermentation of P. freudenreichii with Lactic acid Bacteria (LAB) was successful in producing bread with enriched vitamin B-12 levels (ranging from 0.89 to 1.44 mu g 100 g(-1)). Overall, the co-fermentation of P. freudenreichii presents an opportunity to improve the nutritional value of WMSB.

Automated summary

Co-fermentation of Propionibacterium freudenreichii with Lactic acid Bacteria (LAB) significantly improved the vitamin B-12 content and sensory characteristics of whole-meal sourdough bread.