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Teff (Eragrostis tef (Zuccagni) Trotter) is one of the underutilized crops that can contribute to food security with distinct nutritional values. The present study was aimed to determine the total phenolic content, total fat content, and fatty acid profiles and evaluate the nutritional values of the white and brown Injera (ready‐to‐eat food) using UV‐Vis and GC‐MS methods. The determined free total simple phenolic compound contents, bound total simple phenolic compound contents, and total flavonoid contents were 169.48 ± 3.36–178.52 ± 7.5, 53.13 ± 1.92–60.38 ± 0.82, and 85.18 ± 1.14–117.59 ± 4.31 mg QE/100 g, respectively, in white Injera, and 193.86 ± 6.38–204.90 ± 4.04, 70.25 ± 3.56–82.13 ± 3.12, and 97.31 ± 1.22–107.42 ± 3.29 mg QE/100 g, respectively, in brown Injera. The free total simple phenolic compound contents and bound total simple phenolic compound contents were found higher and lower, respectively, in white and brown Injera. Compared to the reported teff grains and other cereal grains, low linoleic acid (ω‐6) (21.1–24.8%) and high content of α‐linolenic acid (ω‐3) (16.3–18.9%) were found in the white and brown Injera, respectively. This value has much improved the ω‐6/ω‐3 in the white Injera (1.5 : 1) and brown Injera (1.2 : 1) and was surprisingly found consistent with the suggested 1‐2 : 1 ratio. Moreover, the lipid quality of teff Injera was found to be superior to that of other cereal grains, showing that this food product actually contains novel food components with substantial nutritional and health advantages. The results of this study may therefore aid teff consumers, processors, and researchers in raising knowledge of the nutritional value and health advantages of the white and brown Injera, as well as their contents of free and bound phenolics and fatty acid profiles. [ABSTRACT FROM AUTHOR]

A simple, cost-effective, and environmentally friendly 13 C NMR method was developed and validated for the determination of sucrose, fructose, and glucose in aqueous extracts of the flesh, peel, and seed parts of pumpkin. The 13 C NMR method was validated to determine individual sugars using chemical shifts at δ 103.58, 98.07, and 96.45 ppm for sucrose, fructose, and glucose, respectively. The results showed a linear range, 1.08 to 83.3 g/L; R2, of 0.999 to 1.00; LOD, 0.06 to 0.29 g/L; LOQ, 0.21 to 0.97 g/L; RSD, 0.63 to 0.96%; and %recovery, 97.8 to 101.8%. Accordingly, the developed method can easily be applied for the quantitative determination of individual sugars in pumpkin flesh, peel, and seeds. The content of sucrose in the flesh, peel, and seed samples varied from 0.79 to 1.07%, 0.37–0.46%, and 0.14–0.18%, respectively. The amount of fructose was found to be 0.32–0.40% in pumpkin flesh and 0.08–0.18% in pumpkin peel. The pumpkin flesh and peel contained 0.14–0.20% and 0.06–0.08% glucose, respectively. Sucrose was found in higher amounts in all the samples. Fructose and glucose were not detected in the seed parts of pumpkin. Compared to sucrose and glucose, fructose content showed a better correlation between the flesh and peel parts of the pumpkin. [ABSTRACT FROM AUTHOR]

Teff [Eragrostis tef (Zuccagni) Trotter] is cereal grain native to Ethiopia as staple food to millions of people. However, no research work has been reported for characterization with respect to water-soluble total sugars and total free amino acids in white and brown teff grains. The main objective of this study was to determine water-soluble total sugars and total free amino acids (TFAA) in the white and brown teff grain varieties. The determined water-soluble total sugar contents of white and brown teff grain sample extract was ranged between 2.69±0.12 - 4.56±0.08 g GE/100 g and 2.22±0.04 - 4.74±0.19 g GE/100 g, respectively. The mean TFAA contents for white and brown teff samples was found in the range between 181.4±30.0 - 638.9±42.6 mg AE/100 g and 471.7±37.0 - 927.1±32.4 mg AE/100 g, respectively. The mean value of the TFAA in brown teff samples was found higher than that of white teff samples. Pearson correlation was in the opposite direction, indicating that the biosynthetic pathways for the water-soluble total sugars and TFAA in both white and brown teff varieties might be opposite. Therefore, the present study indicated that teff is rich in the water-soluble total sugars and TFAA. [ABSTRACT FROM AUTHOR]

Barley (Hordeum vulgare L.) is one of the most widely cultivated stable food crops in the world. Barley grain samples were collected from four selected areas (Bahir Dar, Bure, Finote Selam and Debre Markos) of Ethiopia and four types of processed food (kolo, porridge, bread and injera) were prepared from it. The levels of essential and non-essential metals in barley grains and its processed food were determined by microwave plasmaatomic emission spectrometry after wet digestion with a mixture of HNO3 and HClO4 (5:1, v/v). The concentration (mg/kg dry weight) in the barley grains were in the ranges K (5482-6516), Mg (546-643), Ca (445-684), Mn (7.31-9.80), Fe (127-439), Cu (0.88-1.86), Zn (42.8-56.8), Pb (0.39-2.73), Cd (3.01-4.66). The concentrations of all the metals in the four types of processed barley foods showed variation among each other. The results indicate that Ethiopian barley grains and its processed foods are good source of essential metals. [ABSTRACT FROM AUTHOR]

The knowledge of the levels of polyphenols present in green coffee beans from different geographical origins is important to identify beans that can provide better coffee quality. The aim of this study was to determine the concentrations of both soluble and cell wall-bound polyphenols in green coffee beans (Coffea arbica L.) from different cultivation regions of Ethiopia. A total of 100 samples were collected from four geographical regions (East, West, South, Northwest) and comprised eight commercial types of coffee (Harar, Jimma, Kaffa, Wollega, Sidama, Yirgacheffe, Finoteselam and Benishangul). The total concentrations of soluble and cell wall-bound polyphenols and flavonoids in the sample extracts were determined using the Folin-Ciocalteu and aluminum chloride reagent methods, respectively. Qualitative analysis was also performed by using high performance thin layer chromatography (HPTLC). Results revealed that chlorogenic acids as the predominant constituents of the phenolic fraction of the green coffee beans. The total soluble polyphenol, cell wall-bound polyphenol and flavonoid contents of the green coffee beans were in the range of 21.8–43.6 milligrams of gallic acid equivalents per gram (mg GAE g−1), 8.6–15.3 mg GAE g−1 and 3.3–6.2 milligrams of (+)-catechin equivalents per gram (mg CE g−1) of dry mass, respectively. Cell wall-bound polyphenols were found to contribute significantly (21.0–32.5%) to the total polyphenol contents (TPC) of the green coffee beans. The polyphenol contents of green coffee beans have been found to vary with geographical origins. Harar coffee contained significantly (p < 0.05) lower amounts of both total soluble and cell wall-bound polyphenols than the other regional coffee types. Furthermore, the contribution of cell wall-bound phenolic to the TPC should not be overlooked. [ABSTRACT FROM AUTHOR]

The levels of selected essential and non-essential metals in the white, red, and mixed teff grains collected from Bure, Debre Markos and Bahir Dar (Ethiopia) were determined by microwave plasma-atomic emission spectroscopy (MP-AES). After proper sample pretreatment, the powdered teff was wet digested with the acid mixture (5 mL HNO3:1 mL HClO4) at 240 oC for 2:30 h over Kjeldhal digestion block. The accuracy of the optimized procedure was evaluated by analyzing the digest of the spiked samples with a standard solution of metals, and the percentage recoveries varied from 92% to 104%. The mean concentrations of metals determined (mg/kg, dry weight) were in the ranges of Al (713-1513) > Fe (252-1195) > Ca (233-348) > Zn (69-102) > Mn (20-45) > Cu (13-15) > Pb (1.8-2.8) > Cd (0.8-1.8). In this study, Al and Cd were determined in the teff for the first time. Analysis of variance indicated no significant difference between the mean concentrations of Cu and Mn among the white teff samples, Mn among the red teff samples and Cd and Pb among the mixed teff samples, but there was a significant difference for the other studied metals among the corresponding teff samples at 95% confidence level. [ABSTRACT FROM AUTHOR]

This study was aimed to identify volatile compounds of 31 green coffee bean samples and evalute their correlation with altitude of the coffee plants grown in two zones (Gedeo and Jimma) in Ethiopia. A total of 81 different compounds were detected. The contents of dominant volatile compounds in green coffee beans were in the range: trans-linalooloxide (3.24-19.13%), linalool (1.56-21.76%), 2-methoxy-4-vinylphenol (2.34-15.08%) and cis-linalooloxide (1.03-13.27%). In addition, benzene acetaldehyde (0.45-10.97%), 2-heptanol (0.67-8.49%), α-terpineol (0.64-6.52%), phenylethyl alcohol (0.44-4.98%) and furfural (0.92-5.3%) were the next dominant compounds. The volatile compounds identified in the green coffee beans are groups of alcohols, aldehydes, ketones, pyrazines, pyridines, and furans. The volatile compounds in green coffee beans showed either weak positive or weak negative correlation with the altitude of coffee plants indicating that variation in altitude of the coffee plants does not significantly influence the volative compounds of green coffee beans. [ABSTRACT FROM AUTHOR]

BACKGROUND This study was aimed at the development of objective analytical method capable of verifying the production region of the coffee beans. One hundred samples of green coffee (Coffea arabica L.) beans from the major producing regions, comprising various sub‐regional types, were studied for variations in their fatty acid compositions by using gas chromatography coupled with mass spectrometry. Principal component analysis (PCA) was used to visualize data trends. Linear discriminant analysis (LDA) was used to construct classification models. RESULTS: Twenty‐one different fatty acids were detected in all of the samples. The total fatty acid content varied from 83 to 204 g kg−1 across the regions. Oleic, linoleic, palmitic, stearic and arachidic acids were identified as the most discriminating compounds among the production regions. The recognition and prediction abilities of the LDA model for classification at regional level were 95% and 92%, respectively, and 92% and 85%, respectively, at sub‐regional level. CONCLUSION: Fatty acids contain adequate information for use as descriptors of the cultivation region of coffee beans. Chemometric methods based on fatty acid composition can be used to detect fraudulently labeled coffees, with regard to the production region. These can benefit the coffee production market by providing consumers with products of the expected quality. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) calculations were carried out on iron(III), nickel(II) and copper(II) complexes of N,N'-ethylenebis(salicylimine) both at molecular level (isolated complexes) and encapsulated in a zeolite framework to investigate changes that occur in their geometrical and electronic parameters as well as in their reactivity and stability. The computational results showed that the zeolite encapsulated metal complexes have higher reactivity and less stability as compared to the isolated metal complexes. [ABSTRACT FROM AUTHOR]