Effect of different fermentation on nutritional and anti-nutritional properties on finger millet products

Abstract

The present research entitled “Effects of Diverse Fermentation on Nutritional and Functional Quality of Finger Millets” was undertaken to evaluate the impact of yeast and bacterial fermentation on the nutritional profile and antioxidant activity of finger millet (Eleusine coracana L.). Finger millet flour was initially subjected to lactic acid fermentation and yeast fermentation (Saccharomyces cerevisiae L.) for 12 hours. The fermented samples were then dried and analyzed for nutritional composition, anti-nutritional factors, mineral content, and antioxidant activity. Subsequently, fermented food products such as cake and beverage were developed using yeast- and bacteria-fermented finger millet and optimized. These food items underwent sensory evaluation, assessing color, flavor, taste, and overall acceptability using a Nine-point Hedonic Scale. Nutritional parameters—including moisture, ash, protein, fat, carbohydrate, energy, iron, fiber, calcium, and phosphorus—were assessed following AOAC (2007) methods. Anti-nutritional factors, including phytate and tannin content, were measured using ion exchange chromatography and the Folin-Denis method, respectively. Total Phenolic Content (TPC) and DPPH radical scavenging activity were analyzed spectrophotometrically to evaluate antioxidant capacity. All data were recorded as the mean of triplicate experiments and analyzed statistically using Two-way ANOVA (Analysis of Variance). Critical Difference (CD) test was used to determine significant differences between treatments. The results indicated that bacterial-fermented finger millet had the highest protein content, followed by yeast-fermented, with raw finger millet showing the least. Yeast fermentation resulted in higher levels of fat (1.90%), fiber (5.67%), and carbohydrate (72.44%). Fermentation significantly reduced anti-nutritional factors and enhanced antioxidant activity, with bacterial fermentation showing a greater enhancement in antioxidant potential. Sensory evaluation results revealed that Treatment T2 was rated the highest in terms of overall acceptability for both cake and beverage formulations.