Physicochemical, antioxidant and microstructural properties of malted finger millet (Eleusine coracana) flour(s) and their use in gluten-free biscuits.

MESHWR

Department of Food Science and Technology

Finger millet is a gluten-free crop with outstanding malting qualities, and a low glycaemic index. The study aimed to determine the physicochemical, antioxidant, and microstructural properties of malted finger millet flours (light and dark brown) and their use in gluten-free biscuits. The two varieties of finger millet grains were germinated for 0, 24, 48, and 72 hours (h) and kilned for 8 h at 30°C. The lightness (L*) values of malted finger millet flours significantly increased (p ≤ 0.05), with light brown having the highest L* value of 76.62. The moisture, ash, fibre, protein, mineral, total phenolic and total flavonoid contents and DPPH activity of both malted finger millet flours and biscuits significantly increased (p ≤ 0.05). Both malted finger millet flours' solubility index, water and oil absorption capacity increased significantly, while the packed and loose bulk density decreased. A significant decrease in the viscosity of the cooked paste in both finger millet flours was observed. Malting resulted in an increase in the onset, peak, and conclusion temperatures. FTIR showed that malting slightly changed the peaks of both finger millet flours. Scanning electron microscopy showed that malting altered the microstructural characteristics of finger millet flours. The yellowness and whiteness index of FM biscuits significantly increased, ranging from 41.47 to 42.12 and 42.21 to 45.47 (light brown) and from 67.78 to 70.97 and 71.92 to 75.41 for dark brown, respectively. The weight, diameter, thickness, and spread ratio significantly decreased with an increase in malting in both FM biscuits. The hardness of the biscuits significantly increased from 762.53 to 1720.28 g (light brown) and 747.50 to 1918.71 g (dark brown). The LB biscuits had more desirable sensory attributes as compared to the DB biscuits. It was concluded that malted FM flour can be used to prepare nutritious and healthier gluten-free bakery products.

National Research Foundation (NRF)