Thermal, functional, and pasting characteristics of flours from selected millet varieties in Nigeria

Abstract

Background: Africans have found millet as a source of plant-based protein and energy. Substitution of other high demand cereals with millets can prove useful as they can improve health and decrease the risks of diseases..

Objective: Proximate, thermal, functional, and pasting properties of millet flours from selected varieties (pearl, finger, kodo and teff) were investigated using standard analytical methods to provide information on their functionalities.

Methods: Pearl, finger, kodo and teff millets were sourced from local markets and processed into flours. The flours were produced using standard procedures, and their samples were analyzed in the laboratory. The results of the analyses were subjected to Analysis of Variance at a significance level of 5% using SPSS.

Results: The proximate composition of the flour samples from the varieties ranged between 5.83-6.87% for moisture content, 1.23-2.50% ash, 2.00-5.33% crude fat, 7.66- 10.29% crude protein, 0.61- 0.81% crude fibre, and 76.50-81.57% carbohydrate. Thermophysical properties of the flours values were specific heat o o capacity (171.73-172.43 kJ/kg C), thermal conductivity (25.11-25.96 W/m C) and thermal diffusivity (0.11-0.13 m²/s). Functional properties of the millet flour were bulk density (1.11-1.31 g/ml), oil absorption capacity
(57.00-80.60%), water absorption capacity (0.80-0.94 g/g), dispersibility (37.67-40.3%), swelling power (8.12-9.41%) and solubility (12.67-16.00%). The pasting properties of millet flours were peak viscosity (1126-1946 RVU), trough (903-1848 RVU), final viscosity (1212-1958 RVU), setback viscosity (110-390 RVU), o pasting time (6.43-6.93 minutes) and pasting temperature (78.80-90.58 C), respectively.

Conclusion: The quality characteristics of the flours showed good nutrient composition, potential for value addition and improved functionality of millet-based food products.