A Comparative Study on Rheological, Functional and Color Properties of Improved Millet Varieties and Injera

Abstract

Millets are important food crops in semi-arid and tropical regions of Africa and Asia. The cooking and eating quality of foods are determined by the rheological, functional and color properties of flours. In this research, four finger millet varieties (Axum, Padet, Tadese and Tesema) and one pearl millet variety (Kola-1) were collected. The aim of this study was to evaluate the rheological, functional and color characteristics of improved millet varieties grown in Ethiopia. A significant (p<0.05) variations were observed among the five millet flours in their pasting profiles. Pearl millet variety, Kola-1 showed the highest flour solubility (12.86%), pasting temperature (77.4°C) and the lowest flour swelling power (195.54 g/g), peak viscosity, trough viscosity, breakdown viscosity, setback viscosity, final viscosity and falling number with a values of 855 cP, 293.5 cP, 561.5 cP, 540 cP, 833.5 cP and 197.5 sec, respectively compared to finger millet varieties. Padet had the highest flour water absorption index (3.24 g/g), pasting profiles (3434 cP, 1704 cP, 1730 cP, 2042 cP and 3746 cP) and the lowest pasting temperature (75.02°C). The water absorption capacity of flours was ranged from 116.11 to 120.68%, the highest for flours from Tesema. Kola-1 was significantly differed in gel length and gel consistency from other varieties and was found to have a short gel length and hard gel. In terms of color properties, Kola-1 had the highest L* (57.11) and �??E (41.85) values for grain, b* (4.21) value for flour, b* (8.4) and �??E (42.14) values for injera. Baking resulted in a significant reduction in L* value and increment in a* and b* color values.