Damirga: A traditional fermented flour for rancidity reduction and revitalizing the popularity of pearl millet

Pearl millet is a nutritious cereal and a staple food security crop in many developing countries. However, its flour has a short shelf life due to rapid rancidity. This study evaluated the effects of the traditional Damirga processing method on the physicochemical properties, colorimetric parameters, and rancidity indicators of flour from two cultivars, Aziz and Baladi Yellow (BY). Damirga-processed flour demonstrated lower fat content (3.6 %), higher carbohydrate content (78.2 %), improved bulk density (1.93 g/cm³), and greater swelling power compared to raw flour. It exhibited an enhanced lightness index (L*), higher whitening index, and lower browning index, as well as reduced lipase and lipoxygenase activities, peroxide value, and comprehensive acid value, indicating lower rancidity. Aziz exhibited higher ash content, fat content, and susceptibility to rancidity, while BY showed higher fiber content, oil absorption capacity, and lightness index. Aziz also had greater water absorption capacity, while BY exhibited significantly higher values for blueness (b), whitening index (WI = 72.06), and a more appealing visual profile. Despite similar bulk density and swelling power, Aziz exhibited higher water absorption capacity, while BY showed greater oil absorption capacity. Optimizing Damirga and cultivar selection offers promising solutions to extend pearl millet flour shelf life. • Cultivars exhibit distinct processing-related traits. • Damirga-processed flour improved physicochemical properties. • Significant genotypic differences in rancidity susceptibility. • Traditional Damirga reduces rancidity in pearl millet flour.