Comparative Study of Chemical Composition, Pasting, Thermal and Functional properties of Teff (Eragrostis tef) Flours Grown in Ethiopia and South Africa

The present study compared whole grain teff flours grown in Ethiopia (ETF) and South Africa (STF) for their chemical composition (proximate, mineral, and amino acid) and pasting, thermal, and functional properties. The proximate composition of flours was determined using methods of the European Commission Regulation (152/2009). Atomic Spectrometer, ion-exchange chromatography, Rapid Visco-Analyzer (RVA), and Differential Scanning Calorimetry (DSC) were used to measure minerals, amino acids, pasting, and thermal properties, respectively. The inter-relationships of the measured attributes were determined using Pearson correlation and principal component analysis (PCA). Significant (p < .05) differences in most of the evaluated properties were found between ETF and STF. However, several significant (p < .01) correlations were observed among the measured attributes of flours as revealed by Pearson correlation and PCA. Significantly (p < .05) higher contents of moisture (11.2 g/100 g flour), protein (13.3 g/100 g flour), and zinc (34.6 mg/kg) were found in STF, whereas significantly (p < .05) higher contents of calcium (1306 mg/kg) and iron (363 mg/kg) were perceived in ETF. The ETF was observed to have higher foam stability (71 mL/100 mL initial foam), water absorption capacity (1.1 g/g), oil absorption capacity (0.9 g/g), and swelling power (6.4 g/g) as compared to STF. Observations from thermal and pasting properties revealed that onset, peak and end temperatures, trough, final and set back viscosities, including peak time (6.3 min), and pasting temperature (90 °C) were found to be higher in the case of STF. In conclusion, findings of this study would contribute to the selection of teff for the development of healthier food products to meet the current consumer preferences .