Guided LAB fermentation unlocks quality potential of wheat-sorghum composite bread

The impact of sorghum flour fermentation with Lactobacillus delbrueckii subsp. lactis 1932, Lacticaseibacillus casei 4339, and Leuconostoc spp. 4454 on quality attributes of wheat-sorghum bread was evaluated. Lcb. casei 4339 and Leu. 4454 promoted the formation of larger pores (>5 mm²) and a more open crumb structure (p < 0.05). Lb. delbrueckii 1932 and Leu. 4454 exhibited greater bread cohesiveness (+4%). A slightly reduced specific volume (-9%) and higher hardness (+30%) were found in Lcb. casei 4339 bread. Fermented sorghum enhanced bread color brightness L* and redness a* (p < 0.05). Leu. 4454 and Lcb. casei 4339 bread showed a richer volatile profile. Only Lcb. casei 4339 bread achieved scores >6.0 ("slightly pleasant") across all sensory attributes, with the best overall appearance (p < 0.05). Overall, guided sorghum lactic fermentation showed its potential to improve structural and aromatic properties, as well as sensory acceptability of wheat-sorghum bread.