Companilactobacillus crustorum LMG 23699 and Wickerhamomyces anomalus IMDO 010110 form a candidate, stable, mixed-strain starter culture for sourdough production.

Companilactobacillus crustorum LMG 23699 is a candidate starter culture for sourdough production. White wheat and wholemeal wheat Type 3 sourdough productions started with this strain showed its competitiveness and robustness. Moreover, starter culture strain monitoring by an amplicon sequence variant approach revealed its prevalence, and unraveled a consortium with the yeast Wickerhamomyces anomalus. Even a temperature perturbation during sourdough storage, which caused an increase in the relative abundance of the background Levilactobacillus parabrevis, could not eliminate this starter culture strain. In addition, Coml. crustorum LMG 23699 always prevailed during wholemeal wheat Type 2 sourdough productions started with different ratios of this strain and Levl. parabrevis IMDO 033007 (isolated from the above-mentioned sourdoughs), with and without W. anomalus IMDO 010110 (isolated from the above-mentioned sourdoughs). When the yeast strain was co-inoculated, the four main flour carbohydrates and mannose were depleted and more D-lactic acid was produced, pointing toward a stable interaction between Coml. crustorum LMG 23699 and W. anomalus IMDO 010110. To conclude, the present study showed that the competitive and robust Coml. crustorum LMG 23699 could form with W. anomalus IMDO 010110 a new, stable, microbial consortium for sourdough productions.