Fermentation of acorn dough by lactobacilli strains: Phytic acid degradation and antioxidant activity

In the current study, the effects of three lactobacilli strains (L. plantarum subsp. plantarum PTCC 1745, L. fermentum PTCC 1638 and L. casei subsp. casei PTCC 1608) on phytic acid content, pH, lactate, total phenolic compounds as well as antioxidant activity of acorn dough during fermentation (37 °C for 24 h) were investigated. According to the results, the number of L. casei subsp. casei was significantly higher than those reported for two other strains during 24 h of fermentation (p-value≤0.05). Moreover, the highest concentration of lactate and the lowest pH was observed in dough containing L. casei subsp. casei. The biggest decrease in the phytic acid content of dough was associated with fermentation by L. plantarum subsp. plantarum. Also, the phytase activity of L. plantarum subsp. plantarum, L. fermentum, and L. casei subsp. casei was measured at 2.77, 2.38 and 2.12 U/mg pro, respectively. Moreover, the highest antioxidant activity was achieved by the L. plantarum subsp. plantarum due to a higher concentration of phenolic compounds produced. Accordingly, among the three mentioned lactobacilli, the application of L. plantarum subsp. plantarum for fermentation of the acorn flour is recommended.