Effect of fermentation time on the physicochemical properties and phenolic composition of malted finger millet beverages

Abstract

Food security is still a significant problem, particularly in less developed nations. Orphan crops, such as finger millet (FM), are essential for meeting dietary and nutritional needs as well as providing a means of livelihood for economies with limited resources in Asia and Africa. Comparing two varieties of FM malt beverages using sorghum grain as an external reference, the research examined the impact of fermentation time on the physicochemical characteristics and phenolic composition of the FM malt beverages. The FM grains were fermented using Lactobacillus fermentum and the grain microflora. The beverages' pH decreased in a time-dependent manner throughout fermentation, and their sugar content increased accordingly. A reduction in the beverages' viscosities for both L. fermentum and the grain microflora was observed. The amount of citric acid in the beverages decreased as fermentation progressed, especially for L. fermentum. Catechin, epicatechin, and protocatechuic acid were the phenolics identified in the FM beverages. An increase in fermentation time was correlated with a decrease in the beverages' total phenolic content. At 96 h of fermentation, the beverages' DPPH, ABTS, and FRAP radical scavenging activities were significantly (p < 0.05) reduced for both L. fermentum and the grain microflora. The 24-h fermented beverages maintained higher amounts of total polyphenols and antioxidant effects. The findings indicate that FM may be utilized as a functional grain to produce nonalcoholic beverages with health benefits.