Synergistic enhancement of iron, folate, and antioxidant properties in pearl millet via RSM-optimized probiotic fermentation with Lactiplantibacillus plantarum

Fermentation stands as one of the most ancient and extensively employed techniques, continuously evolving as a technology dedicated to enhancing the nutritional qualities of food. In the present study, probiotic fermentation conditions for pearl millet flour using Lactiplantibacillus plantarum were optimized for exploring the potential of enhancing iron, folate and antioxidant activity. A central composite experimental design with three independent variables, temperature (30 °C-50 °C), pH (3–7) and fermentation time (4–30 h) was used to study the dependent variables (antioxidant activity, tannin, phytic acid, total reducing sugar, total dietary fibre, iron and folate). Based on response surface methodology, twenty runs were processed. Regression model interpretation revealed the significant relationship between considered dependent and independent variables (p < 0.05). The optimized conditions for probiotic fermentation of pearl millet were temperature 40 °C, fermentation time of 38.86 h and pH 5. At optimized conditions a significant enhancement in iron content of 56.74 % and folate upto 23.1 % was observed. Considerable increase in DPPH% i.e. 26.6 %, FRAP 36.51 %, ABTS 15 %, TPC 4.72 % and TFC 14.63 % was also observed. The research showed that L. plantarum strain can be used not only for potential folate enhancement but also for increased antioxidant activity and reduced antinutrients.