Images dataset of pure and adulterated Teff (Eragrostis tef (Zucc.) Trotter) flour with wood flour (sawdust) and gypsum (calcium sulfate) powder for machine learning based identification of Teff flour adulteration and prediction of the level adulteration

This study investigated quality characteristics and sensory properties of gluten-free bread using teff flour and various gums. The five samples used in this study were control (wheat flour), T (teff flour), TG (teff flour, guar gum), TX (teff flour, xanthan gum), and TGX (teff flour, guar gum, xanthan gum). Baking loss, moisture content, pH, salinity, brix, dough expansion, color value, texture property, and sensory property were measured for each sample. As a result, pH was the highest in TX at 6.11 and the lowest in the control at 5.77. Salinity was the highest in the control at 0.80% and lowest in TG at 0.04%. Brix was the lowest in TX at 1.10 °Bx. While moisture content was the highest in the control at 43.58%, gluten-free breads using teff flour had no significant difference (p<0.05). Baking loss rate of bread was no significant difference among samples (p<0.05). Dough expansion rate by fermentation was the highest in the control at 108.89% and the lowest in T at 17.84%. L-value of crust had no significant difference (p<0.05). For L-value of crumb, the control was the highest at 64.34 and T was the lowest at 33.84. In texture properties analysis, hardness was the highest in TGX at 16.00 N and the lowest in the control at 2.87 N. There was no significant difference in springiness (p<0.05). Chewiness was the highest in TX and TGX. The result of sensory properties was that while there were no significant differences in color, salty taste, flavor, and overall acceptability, there was a significant difference in softness and sweetness (p<0.05). These results showed that use of teff flour and gums rather than using only teff flour for bread manufacturing can improve quality characteristics in dough expansion and texture properties. It is considered that xanthan gum or guar gum are appropriate on bread using teff for quality characteristics.

SummaryThis article aimed to evaluate the chemical, technological and sensory characteristics of gluten‐free cakes made with teff (Eragrostis tef). Four cakes were evaluated: T1, 100% teff flour; T2, 75% teff flour, 12.5% rice flour, 12.5% cassava starch; T3, 50% teff flour, 25% rice flour, 25% cassava starch and T4, 25% teff flour, 37.5% rice flour, 37.5% cassava starch. Higher percentages of teff increased total ash. For apparent and specific volumes, T4 was the one with the highest mean. In sensory analysis, the attributes of appearance, colour and odour did not have significant difference among treatments. T1 received the lowest overall average for flavour (5.03). Regarding the purchase intention, the cakes did not show significant difference between T3 and T2 (3.25 and 3.08). T2, T3 and T4 obtained acceptance index higher than 70%. The use of teff flour in cakes can be promising in gluten free diet.

In recent years, several studies have shown the antioxidant and antihypertensive potential of bioactive peptides. Thus, bioactive peptides are likely to be a valuable substance for the development of functional foods. There are a wide variety of sources of these peptides, including several cereals. Teff is an Ethiopian-rooted cereal with an interesting nutritional profile, mainly due to its high amount of protein. In this study, teff flour was subjected to a defatting process for optimizing the protein extraction. Such extraction was performed by precipitation from its isoelectric point, a crucial step that separates the protein from other components based on their charge. The protein obtained was subjected to enzymatic hydrolysis by pepsin and Cynara cardunculus L. The antihypertensive (angiotensin-I-converting enzyme -ACE-I- inhibitory activity) and antioxidant activity (2,2-diphenyl-1-picrylhydrazyl -DPPH- radical scavenging activity) of the peptides were determined. According to the IC50 values, the results obtained showed that the peptides from teff flour show promising bioactivity compared to other cereals. Furthermore, the peptides from teff flour obtained from C. cardunculus L. showed higher antioxidant activity (defatted teff flour -DTF-: 0.59 ± 0.05; protein extract -EP- : 1.04 ± 0.11) than those obtained with pepsin (DTF: 0.87 ± 0.09; EP: 1.73 ± 0.11). However, C. cardunculus L. hydrolyzate peptides showed lower inhibitory activity of ACE-I (DTF: 0.59 ± 0.07; EP: 0.61 ± 0.05) than the pepsin hydrolyzate (DTF: 0.15 ± 0.02; EP: 0.33 ± 0.05).

Reduction of pesticide residues from teff (Eragrostis tef) flour spiked with selected pesticides using household food processing steps

Teff [Eragrostis tef (Zucc.) Trotter] is an underutilised cereal crop grown mainly in Ethiopia and Eritrea. It is an excellent source of dietary fibre, vitamins, minerals and bioactive compounds. However, it also contains a high amount of phytic acid, which is an antinutrient and reduces the bioavailability of minerals and proteins. To improve the nutritional quality of teff, the phytic acid content should be reduced by an effective dephytinisation method. In this study, various dephytinisation methods (fermentation, autoclaving and phytase treatment) were used to dephytinise teff flour. Undephytinised and dephytinised teff flour was mixed into wheat flour (0-40 %) to improve the functional properties of cookies. Twenty different cookie formulations were prepared according to 4x5x2 factorial design. The physical, chemical, nutritional and sensory properties of the cookies were investigated. Among the dephytinisation methods, fermentation produced the most effective reduction in phytic acid mass fraction (181 mg/100 g), followed by phytase treatment (198 mg/100 g). The protein, fat, Fe and Zn content and antioxidant activity of cookies enriched with dephytinised teff flour were comparable to cookies fortified with undephytinised teff flour. Moreover, the dephytinised teff cookies had lower phytic acid mass fractions. The cookies containing 40 % teff flour had higher antioxidant activity and nutritional quality than the control wheat cookies. The use of dephytinised teff flour reduced the spread ratio and the a* and b* values of cookies compared to undephytinised flour. Cookies containing fermented and phytase-treated teff flour had a harder texture than cookies containing undephytinised flour. In addition, as the amount of teff flour increased, the spread ratio values of cookies gradually incrased while their hardness decreased. Overall acceptability scores of cookies containing 10-20 % teff flour were similar to the control. To the best of our knowledge, this is the first study to determine the quality of cookies containing dephytinised teff flour. The data highlight the potential of dephytinised (especially autoclaved and phytase-treated) teff flour (up to 20 %) as a functional ingredient to enrich the mineral content and antioxidant capacity of foods. Furthermore, this study shows that fermentation, autoclaving and phytase treatment can be used to improve the nutritional quality of grains.

Technological Evaluation of High Fiber And Gluten-Free Breads Made With Teff (Eragrostis tef) and Associated Flours

Physico-Chemical and Sensory Evaluation of Gluten-Free Cakes Made with Teff (Eragrostis tef)

This study examined the effect of calcium sulfate additions on the microstructure and frictional properties of a 95bronze-5graphite material, commonly used for frictional applications. The samples were prepared using a powder metallurgy process. The calcium sulfate powder was obtained from recycled plaster molds previously used for ceramic slip casting. The plaster molds were cleaned, crushed and ball milled to obtain powder, which was calcined at 400 °C for 4 hours and screened. 2 to 8 weight percent calcium sulfate powder was added to a premixed powder composed of copper and tin and mixed before the graphite was added. The powder mixture was compacted into a disc shape under a pressure of 500 MPa. The compacted samples were sintered at 750 °C for 30 minutes in a reducing atmosphere. It was found that the green density of the samples decreased with increased amounts of calcium sulfate. After sintering, the densities were found to have decreased due to sample expansion. A finer microstructure was observed in the samples containing calcium sulfate powder, possibly due to a grain boundary pinning effect. The addition of calcium sulfate resulted in the reduction of both the measured friction coefficient and wear of the bronze-graphite samples. However, the addition of calcium sulfate powder above 6 weight percent appeared to show decreasing effects.

Teff (Eragrostis tef) has gained wide popularity mainly attributed to its gluten-free nature catering the needs of gluten-sensitive population. The higher water absorption capacity and gelling properties of teff flour promote its food applications, especially in the baking sector. The nutritional and sensorial properties of teff flour have been studied by incorporating with wheat flour at different proportions, but no study has reported the impact of various milling methods on the rheological and bread-making properties of teff flour. In this regard, the present study is envisaged to assess the physical, rheological, and bread-making properties of teff flour acquired over roller, hammer, and pin milling. Among the milling methods, the distribution of particles was more uniform in case of roller mill, while finer particles were obtained for the pin milled flour fractions with 60% of the sample falling below 90 μm. It was observed that the protein, crude fiber, and crude fat contents for all the flours were on par with each other irrespective of the milling method. Whereas, the pasting properties varied significantly between the flours obtained from different milling methods. It was observed that the pin milled flour bread was superior in quality owing to its higher loaf volume (331.67 cm3 ) with lower hardness value (5.99 N). The present study indicates the fact that pin mill could be more suitable for milling brown teff grains owing to the better pasting and bread-making properties.

Teff (Eragrostis tef, Zucc) is the smallest grain commonly cultivated in Ethiopia and Eritrea and is used mainly to prepare pancake-like staple food called flatbread (Injera). It has substantial national and global recognition due to its nutraceutical benefits and its gluten-free nature. Flatbread, a functional food for health promotion, can be enhanced with less mineral-rich crops like Amaranthus, which are often underutilized, to increase its nutritional and mineral content. Thus, the study is aimed at studying the nutritional, sensory, and storage period of flatbread by incorporating amaranth leaves and grain powders into teff flour. Experiments were designed (using Minitab software, v.19.1), and flatbread was prepared by altering the proportions (grams) of Amaranthus leaf and grain flour incorporated with teff flour in ratios of 2:98, 4:96, 6:94, 8:92, and 10:90 (w/w), teff being the significant component in each blend. The results revealed that most of the nutritive components (except carbohydrates and chromium (Cr)) improved significantly due to the incorporation of both (Amaranthus leaf and grains). Minerals such as sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), and zinc (Zn) increased noticeably (in percent), ranging from 10% to 12.2%, 0.02%-0.41%, 3%-4.4%, 0.33%-2.2%, 5.7%-10%, and 4.9%-28.7%, respectively. Furthermore, lower proportions of Amaranthus grain flour (2, 4, and 6 g blending) and leaf flour (2-10 g blending) significantly extended the storage period of blended flatbread up to 6-7 days, where higher proportions of Amaranthus grain (8 and 10 g blending) are expected to preserve the flatbread Injera up to 9-10 days, surpassing the 3-4 days of the control (100 g teff flour). Therefore, novel teff-Amaranthus blended food can be produced by means of a cost-effective and easy-to-produce new integrated teff-Amaranthus blended food that can enhance the nutritional value and shelf life of the existing teff Injera.

Physical and Sensorial Evaluation of Breads Prepared with Teff Flour (Eragrostis tef) Associated with Whey Protean and Cassava Starch

In this study, calcium sulfate(gypsum) powder was obtained using waste sulfuric acid and stainless steel refinery sludge by-produced from chemical reagent and the iron industry, by the neutralization of waste sulfuric acid. As variables for the experiment, the molar ratio of the H2SO4: Ca(OH)2, the pH, the reaction temperature and time, the amount of catalyst were used. The crystal shape and microstructure of obtained powder were observed by XRD and SEM, and the thermal property was investigated by DTA. As the NaCl is added 0–20 wt.% as a catalyst to the H2SO4-Ca(OH)2 system, it can be found that the crystal shape goes through the processes as follows; gypsum dehydrate gypsum → gypsum hemihydrate + gypsum dihydrate → gypsum hemihydrate. And gypsum hemihydrate is δ-type as the result of DTA. As waste sulfuric acid and stainless steel refinery sludge were used, the pH of reacted solution (which was 0.8) was rapidly raised up to 8–9 by the addition of stainless steel sludge and gypsum dihydrate was produced as a by-product. Therefore, it was found that stainless steel refinery sludge is sufficiently applicable for the neutralization of waste sulfuric acid.

This study analysed the contents of thirty-six mineral and trace elements in teff (Eragrostis tef L.) grains. What is more, dietary intakes were calculated. Inductively coupled plasma mass spectrometry (ICP-MS) was used to assess mineral and trace element contents. Consequently, the appropriate Recommended Dietary Allowance (RDA) or adequate intake (AI), and provisional tolerable weekly intake (PTWI) or provisional tolerable monthly intake (PTMI) values for adults were determined according to the Food and Agriculture Organization/World Health Organization (FAO/WHO) and Institute of Medicine (IOM) regulations. Teff is a significant contributor to RDAs and AIs for females in the following order: Mn > Cu > Zn ≥ Mg > Fe ≥ P and Ca. For males, teff contributes in the order, Mn > Cu > Fe > Zn ≥ P ≥ Mg > and Ca. The concentration of arsenic (65.9 µg/kg) in brown teff originating in Bolivia exceeded the average acceptable value set by Reg. No. 1881 of 6–50 µg/kg in cereals consumed in the EU. The PTWIs or PTMIs for Al, Cd, Sn and Hg were all under 7%, which is below the limits of toxic element intake related to the body weight of 65 kg for adult females and 80 kg for males, set by the FAO/WHO. Teff grains can be recommended as a valuable and safe source of minerals and trace elements.

Teff [Eragrostis tef (Zuccagni) Trotter] is a cereal grain originating in Ethiopia as a staple food for millions of people. Its grain is a gluten-free superfood and got acceptance as a medicinal ingredient. Therefore, it is worthwhile to determine the antioxidative activities and L-ascorbic acid contents of teff grain and its baked food (injera). This study aimed to determine the ascorbic acid contents and antioxidant activities in the aqueous extract of the white and brown teff grains and their injera samples using iodimetric titration and UV-Vis spectrophotometric methods, respectively. The ascorbic acid contents in the white and brown teff ranged from 67.9–112.6 mg/100 g and 69.2–117.2 mg/100 g, respectively, and those in injera of the selected teff samples ranged from 30.5–32.9 mg/100 g and 37.3–43.0 mg/100 g, respectively. The antioxidant activities ranged from 1.26–7.04 μmol AAE/g for the white teff grains, 1.44–6.29 μmol AAE/g for the brown teff grains, 1.81–2.47 μmol AAE/g for white teff injera, and 3.89–4.86 μmol AAE/g for the brown teff injera samples. Findings of the present study have revealed that white teff and brown teff grains and their injera were found to have a higher content of ascorbic acid than commonly consumed grains and vegetables. No significant difference (α = 0.05) has been observed between the two varieties of teff grains with respect to the ascorbic acid content and antioxidant activities. However, there was a statistically significant difference (α = 0.05) in the ascorbic acid content and antioxidant activities between the teff grains and their injera samples. Therefore, this study indicated that teff grains and injera are rich in ascorbic acid content and antioxidant activities as compared to other cereal grains and are very crucial for human nutrition and health.

This study examined the effect of waste-derived calcium sulfate additions (2 to 8 weight percent) on the tribological properties of a sintered high-carbon steel material, commonly used for frictional applications. The calcium sulfate powder was obtained by crushing and subsequent calcination of waste plaster molds previously used for slip casting of ceramics. Samples were made using the powder metallurgy method. Powder mixtures were uniaxially die compacted and sintered at 1,100°C for 30 minutes in a reducing atmosphere. It was found that the density of the samples decreased with increased amounts of calcium sulfate. This was due to the lower theoretical density of the calcium sulfate as well as volumetric expansion of the samples. Ball-on-disc tribological testing was performed at room temperature. The addition of calcium sulfate resulted in an increase of the kinetic friction coefficient. The measured wear volume was slightly reduced with the addition of calcium sulfate less than 6 weight percent, beyond which the wear increased. The hardness of the samples was reduced with the addition of calcium sulfate. Increased calcium sulfate content decreased the sample deformation resistance while increasing the kinetic friction coefficient and the wear. This was likely due to the microstructural changes of the samples, which will be discussed.