Lactic acid production from wasted dates in Saudi Arabia using Single Culture Lactobacillus casei ATCC 393 and Lactobacillus acidophilus and mixed culture

摘要

Production of palm dates in the Kingdom of Saudi Arabia (KSA) is estimated to be over 1 million metric tons annually, which in turn produce a 20% of dates residue annually. In accordance to that, this study aimed at making use of the wasted date to produce lactic acid through the fermentation process, using single culture Lactobacillus casei (ATCC393) and Lactobacillus acidophilus (CICC 6088) and mixed culture of both strains. To investigate the effect of single and mixed culture on the productivity of lactic acid, the fermentation was carried out by using date syrup of 41g/L of sugar (glucose and fructose) for 72 hr of fermentation at a 37 o C, within a pH between 5 to 7, where 34, 36 and 33 g/l were produced at the highest concentrations of lactic acid at 60hr,with productivities of 0.56, 0.60 and 0.55 g/l.hr, respectively. It was found that the single culture CICC 6088 achieved the highest productivity (0.6 g/l.hr) of lactic acid comparing with ATCC 393 and Mixed culture.