Same was the case with MnSO4 · 4H2O, being 96.82% significant for lactic acid production and since had a negative effect, its lower concentration was used for further optimization. Tri-sodium citrate and sodium succinate were also insignificant; were negative in terms of their effect, and were eliminated. Date juice was significant at 99.99% level and produced 16.86 g/l lactic acid, which was the highest among all the 15 components. Comparison of these components for the lactic acid production in Plackett–Burman design showed that trial number 15 showed maximum lactic acid production as compared to the other trials