Evaluation of potential lactic acid bacteria single starter cultures for production of traditional Ivoirian cereal beverages

Twenty-three lactic acid bacteria (LAB) previously isolated from tchapalo process were evaluated as single starter cultures for traditional Ivoirian beverages production. These LAB were inoculated separately into sorghum wort and fermented at 30 °C for 12 h. During fermentations, pH, titratable acidity, and LAB growth were determined. After that, the six better bacteria had been used to produce controlled sour wort, sweet wort and tchapalo. Then, pH, titratable acidity, total soluble solids, and organic acids were analyzed. Their antimicrobial activities also were tested. Within 6 h of fermentation, out of twenty-three bacteria, only six (26.08%) of strains namely L. fermentum strains S6, S42 and S45, P. acidilactici strains S7 and S52 and P. pentosaceus strain S5 accelerated fermentation by dropping of ΔpH to ≥ 1.5 units and increasing of ΔAT to ≥ 0.15%. Lactobacillus fermentum strain S6 carried out his exponential growth rate from 0.18 log CFU/mL to 2.67 log CFU/mL during 2 to 6 h. The sour wort obtained by using of these strains were like those of controls. Tartaric and lactic acids were detected in all the fermented beverages with single starter cultures with a predominance of lactic acid, but their contents varied according to starter cultures. Some sweet wort and tchapalo produced with single starter cultures were able to inhibit the growth of Escherichia coli, Salmonella typhi and Staphylococcus aureus. These six LAB would be used single to improve safety of sweet wort and tchapalo.