| Literature DB >> 27489554 |
Habteab M Ghebrehiwot1, Hussein A Shimelis1, Kevin P Kirkman2, Mark D Laing3, Tafadzwanashe Mabhaudhi4.
Abstract
Injera is a fermented, sour bread consumed as a staple food in Eritrea and Ethiopia. The bread can be prepared from various cereals but tef [Eragrostis tef (Zucc.) Trotter] is the most preferred ingredient. This study assessed the acceptability of injera prepared using grains of a closely related but underutilized grass, Eragrostis curvula (Schrad.) Nees. The nutritive value of the grains was compared and the sensory attributes of injera made from flours of tef (control) and E. curvula, each combined with 0, 5, and 10% of sorghum flour, were assessed using a tasting panel. Nutrient analysis showed that E. curvula contains more than double the amount of crude protein found in tef. E. curvula also contains higher fat, dietary fiber and mineral nutrients than tef. Injera made of E. tef and E. curvula flours showed non-significant differences in taste, texture, appearance and overall acceptability. This suggest that E. curvula has the potential to serve as a novel source of gluten-free flour for human consumption. Agronomically viewed, growing E. curvula could be more advantageous for smallholder farmers on marginal lands because the species is a perennial that can produce a seed harvest twice a year, unlike tef, which is annual crop. It also tolerates acidic soils better than tef.Entities:
Keywords: Eragrostis curvula; injera; sensory evaluation; tef; underutilized crops
Year: 2016 PMID: 27489554 PMCID: PMC4951527 DOI: 10.3389/fpls.2016.01059
Source DB: PubMed Journal: Front Plant Sci ISSN: 1664-462X Impact factor: 5.753
Composition of the six blends of flour prepared for making injera from tef flour and .
| A1 | 250 | 0 | 0 | B1 | 250 | 0 | 0 |
| A2 | 250 | 12.5 | 5 | B2 | 250 | 12.5 | 5 |
| A3 | 250 | 25 | 10 | B3 | 250 | 25 | 10 |
Figure 1The six injera products prepared from . (A1), tef + 0% sorghum; (A2), tef + 5% sorghum; (A3), tef + 10% sorghum; (B1), E. curvula + 0% sorghum; (B2), E. curvula + 5% sorghum; (B3), E. curvula + 10% sorghum.
Nutrient analysis of whole grains of .
| Ash | g/100 g | 2.49 ± 0.03 | 3.18 ± 0.03 | |
| Fat | g/100 g | 2.64 ± 0.02 | 2.83 ± 0.05 | |
| ADF | g/100 g | 7.50 ± 0.64 | 18.34 ± 0.10 | |
| NDF | g/100 g | 11.78 ± 0.57 | 24.30 ± 0.29 | |
| Crude-protein | g/100 g | 8.28 ± 0.04 | 18.47 ± 0.05 | |
| Ca | mg/100 g | 0.19 ± 0.04 | 0.22 ± 0.00 | |
| Mg | mg/100 g | 354.18 ± 1.16 | 115.00 ± 0.63 | |
| K | mg/100 g | 0.42 ± 0.06 | 0.584 ± 0.03 | |
| Na % | mg/100 g | 0.01 ± 0.00 | 0.00 ± 0.00 | |
| K/Ca+Mg | mg/100 g | 0.44 ± 0.02 | 0.48 ± 0.00 | |
| P | mg/100 g | 0.42 ± 0.00 | 0.41 ± 0.05 | |
| Zn | mg/100 g | 37.30 ± 0.81 | 51.43 ± 0.07 | |
| Cu | mg/100 g | 4.27 ± 0.08 | 10.02 ± 0.14 | |
| Mn | mg/100 g | 354.18 ± 1.17 | 114.94 ± 0.64 | |
| Fe | mg/100 g | 50.78 ± 1.08 | 84.53 ± 0.93 |
Moisture % of samples as received by laboratory. NPN is non-protein nitrogen. ADFN and NDFN are calculated as nitrogen. Nitrogen % is calculated by dividing Protein by 6.25. The K/Ca + Mg should not be more than 2. Data on 100% dry matter basis.
Significant difference at 5% level of significance.
Highly significant difference at 1% level of significance.
Distribution of responses on a hedonic scale of 1–5 (bad to good), with resulting statistical indices for the six injera blends testing for taste, texture, appearance, and general acceptance.
| Injera varieties | A1 | A2 | A3 | B1 | B2 | B3 | |
| pH | 3.8 | 4.1 | 4.0 | 3.9 | 3.8 | 3.8 | |
| Dislike very much | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dislike moderately | 2 | 0 | 0 | 1 | 1 | 2 | 2 |
| Neither like nor dislike | 3 | 1 | 1 | 2 | 2 | 1 | 1 |
| Like moderately | 4 | 6 | 2 | 4 | 2 | 6 | 4 |
| Like very much | 5 | 3 | 7 | 3 | 5 | 1 | 3 |
| Total responses | 10 | 10 | 10 | 10 | 10 | 10 | |
| Mean rating | 4.2 | 4.6 | 3.9 | 4.1 | 3.6 | 3.8 | |
| SE | 1.14 | 1.30 | 0.71 | 0.84 | 1.05 | 0.71 | |
| % “Like” responses | 90 | 90 | 70 | 70 | 70 | 70 | |
| Dislike very much | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dislike moderately | 2 | 0 | 0 | 0 | 0 | 1 | 0 |
| Neither like nor dislike | 3 | 1 | 0 | 1 | 1 | 0 | 3 |
| Like moderately | 4 | 4 | 1 | 6 | 4 | 8 | 5 |
| Like very much | 5 | 5 | 9 | 3 | 5 | 1 | 2 |
| Total responses | 10 | 10 | 10 | 10 | 10 | 10 | |
| Mean rating | 4.4 | 4.9 | 4.2 | 4.4 | 3.9 | 3.9 | |
| SE | |||||||
| % “Like” responses | 90 | 100 | 90 | 90 | 90 | 70 | |
| Dislike very much | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dislike moderately | 2 | 0 | 0 | 0 | 0 | 1 | 0 |
| Neither like nor dislike | 3 | 0 | 0 | 0 | 0 | 3 | 2 |
| Like moderately | 4 | 6 | 1 | 4 | 2 | 5 | 3 |
| Like very much | 5 | 4 | 9 | 6 | 8 | 1 | 5 |
| Total responses | 10 | 10 | 10 | 10 | 10 | 10 | |
| Mean rating | 4.4 | 5.0 | 4.8 | 4.8 | 3.8 | 4.1 | |
| SE | |||||||
| % “Like” responses | 100 | 100 | 100 | 100 | 60 | 80 | |
| Dislike very much | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dislike moderately | 2 | 0 | 0 | 0 | 0 | 0 | 0 |
| Neither like nor dislike | 3 | 0 | 0 | 0 | 0 | 2 | 0 |
| Like moderately | 4 | 5 | 0 | 2 | 2 | 6 | 4 |
| Like very much | 5 | 5 | 10 | 8 | 8 | 2 | 6 |
| Total responses | 10 | 10 | 10 | 10 | 10 | 10 | |
| Mean rating | 4.5 | 5.0 | 4.8 | 4.8 | 4.0 | 4.6 | |
| SE | |||||||
| % “Like” responses | 100 | 100 | 100 | 100 | 80 | 100 | |
The injera were; tef (A1 = 0%, A2 = 5%, and A3 = 10% sorghum flour added) and Eragrostis curvula (B1 = 0%, B2 = 5%, and B3 = 10% sorghum flour added).
Mean rating values in the same row with shared letter(s) are not statistically different according to Duncan's multiple range test at 5% level of significance.
Chi-square values comparing the six flour blends using the Kruskal–Wallis non-parametric test and Pair-wise comparison of the six injera using the Mann–Whitney .
| 1 | A1 and A2 | 19.00 | 25.00 ns | 20.00 | 25.00 ns |
| 2 | A1 and A3 | 49.5 ns | 45.00 ns | 30.00 ns | 35.00 ns |
| 3 | A1 and B1 | 40.5 ns | 34.00 ns | 30.00 ns | 35.00 ns |
| 4 | A1 and B2 | 37.00 ns | 36.00 ns | 31.00 ns | 30.00 ns |
| 5 | A1 and B3 | 41.5 ns | 36.50 ns | 37.00 ns | 45.00 ns |
| 6 | A2 and A3 | 27.00 ns | 30.00 ns | 40.00 ns | 40.00 ns |
| 7 | A2 and B1 | 37.00 ns | 40.00 ns | 40.00 ns | 40.00 ns |
| 8 | A2 and B2 | 12.00 | 10.00 | 10.00 | 10.00 |
| 9 | A2 and B3 | 17.00 | 10.00 | 10.00 | 30.00 ns |
| 10 | A3 and B1 | 43.00 ns | 39.00 ns | 50.00 ns | 50.00 ns |
| 11 | A3 and B2 | 39.5 ns | 31.50 ns | 17.00 | 18.00 |
| 12 | A3 and B3 | 43.00 ns | 32.00 ns | 19.00 | 40.00 ns |
| 13 | B1 and B2 | 32.5 ns | 19.00 | 17.00 | 18.00 |
| 14 | B1 and B3 | 36.00 ns | 19.00 | 19.00 | 40.00 ns |
| 15 | B2 and B3 | 46.50 ns | 49.5 ns | 41.50 ns | 26.00 ns |
| Chi-Square | 11.63 | 18.46 | 24.93 | 19.45 | |
| Df | 5 | 5 | 5 | 5 | |
| Significance level | 0.040 | 0.020 | 0.000 | 0.002 |
Denotes significant difference and ns, non-significant difference both at 5% level of significance.
Figure 2Web-chart of the four sensory attributes of injera prepared from tef flour and .