Metals in green coffee beans from major coffee-growing regions of Ethiopia

2019 ◽  
Author(s):  
Chem Int

The metal contents of green coffee beans cultivated in major coffee growing zones of Ethiopia (Wollega, Sidamo, Harar, Bench Maji and Kafa) have been determined in representative samples of the five coffee varieties collected from Coffee Quality Inspection and Liquoring Center located in Addis Ababa, the capital city of Ethiopia. Different sample preparation procedures were tested by varying reagent volumes and types, digestion time, digestion temperature and amount of the sample to decompose the green coffee beans and solubilize the metals. The optimal procedure required 4 h to completely digest 0.5 g of green coffee beans with 5 mL HNO3 (70%) and 1.5 mL HClO4 (70%) at 270 oC. Concentrations of metals (Ca, Cd, Cr, Co, Cu, Fe, K, Mg, Mn, Ni, Pb and Zn) were determined by flame atomic absorption spectrometer employing a four point external calibration curve. The accuracy of the optimized procedure was evaluated by analyzing sample digests spiked with standard solutions. Recoveries of the spiked samples varied from 90 to 110% in green coffee beans. The metals levels observed in green coffee beans are comparable to literature reports. Cd was not detected in any of the five samples while Pb was detected at trace level in only one of the five samples. This indicated that the Ethiopian green coffee beans are free from the toxic metals. The Pearson correlation coefficients indicated strong to medium positive or negative correlation among the metals in the green coffee beans. The analysis of variance results at 95% confidence level suggested that there were significant difference in the concentrations of all the metals except K between the five sampling areas. Thus, this study has revealed variation of metal composition of green coffee beans with the geographical origin of the coffee verities. The variation in composition among coffee sample might be due the differences in mineral contents of the corresponding soils.

Jurnal NERS ◽  
2017 ◽  
Vol 9 (1) ◽  
pp. 26 ◽  
Author(s):  
Joko Setyono ◽  
Dwi Adi Nugroho ◽  
Mustofa Mustofa ◽  
Saryono Saryono

Introduction: Obesity prevalence is estimated increases, reached 19.1% of the population aged 15 years and over. This study aimed to determine the differences of the anti- obesity effect of orlistat, an extract of green coffee beans (Coffea canephora robusta), and its combination to the adiponectin levels and lipid profi le. Method: This research was true experimental post -test only with control group design with completely randomized design (CRD). Experimental animals (Rattus novergicus) were divided into 6 group, group 1 ( negative control ), group 2 ( positive control ), group 3 was group of obese rats fed orlistat dose of 15.9 mg/kg, group 4 was the group of obese rats were fed ethanol extract of green coffee beans dose of 400 mg/kg, group 5 was the group of obese rats were given water extract of green coffee beans dose of 400 mg/kg, and group 6 was group of obese rats were fed a combination of orlistat dose of 15.9 mg/kgand ethanol extract of green coffee beans at a dose of 400 mg/kg. Lipid profi les and adiponectin levels were measured with a spectrophotometer at 500nm absorbance. The data were analyzed by one-way ANOVA, and then post hoc Least Significant Difference (LSD) with α = 0.05. Result: Ethanol extract of green coffee is more effi cient in lowering LDL cholesterol, increasing HDL cholesterol, and lowering the total cholesterol levels on HFD diet-induced mice, but there was no difference in lowering triglycerides . The combination of ethanol extract of green coffee with orlistat showedthe increasing of adiponectin levels were highest than the other treatment groups. Discussion: The ethanol extract of green coffee readily diffuses through the digestive tract epithelium. Green coffee contains chlorogenic acid active compounds that can increase the body’s metabolism, increase fatty acid oxidation, reduce levels of triglycerides in the liver, and working to inhibit lipase and amylase pancreaticenzymes. In addition to chlorogenic acid, polyphenol content in coffee is also potentially reduce visceral fat accumulation. Preparations extract by ethanol allows the absorption process is done effi ciently and quickly.Keywords: obesity, orlistat, greencoffee, lipid profi le, adiponectin


2021 ◽  
Author(s):  
CI Chemistry International

The aim of this study was to evaluate the macro- and micro essential and non-essential minerals in apple fruits collected from farmland in Wollega, Chencha, Ankober (Ethiopia) and Addis Ababa which are imported to Ethiopia from South Africa and Israel. Samples were wet-digested using 3 mL HNO3 and 1 mL HClO4 for 2:15 hours at 210 oC. Selected metals (Mg, Ca, Fe, Mn, Cu, Al, Zn, Cr, Co, Ni, Cd and Pb) were determined by microwave plasma-atomic emission spectroscopy. The validity of optimized procedure was evaluated by the analysis of spiked samples and recoveries were in 90.8-106% range. The mean concentration range (mg/kg) of metal in fruit samples were Ca (1065-36275, 1013-36143), Mg (27-153, 78.3-139), Fe (103-276, 123-241), Mn (13.5-13.7, 11.5-16.3), Cu (5.13-6.56, 4.11-12.6), Al (77.8-129, 52.5-89.6), Zn (41.3-73.6, 47.4-54.4), Cr (6.15-10.04, 6.57-7.14), Co (6.57-7.14, 1.70-2.35), Ni (1.33-2.37, 1.43-7.66), respectively. Cd and Pb were not detected. Analysis of variance showed significant difference (p = 0.05) in the levels of Cu, Al and Co among sampling sites in green apple fruit while all the other metals did not show significance difference. Red apple fruit showed a significance difference in the levels of Fe, Mn, Cu, Zn, Cr and Co metal while the other metals showed insignificance differences. Pearson correlation coefficients indicated strong, moderate and weak correlation between different pairs of metals in both the green and red apples.


1969 ◽  
Vol 43 (2) ◽  
pp. 128-131
Author(s):  
D. S. Boyce

It has been shown that the methods utilized to process coffee cherries to dry coffee parchment affect to a considerable extent the ease with which the silver skin may be removed from the green coffee bean subsequently. Natural fermentation is significantly more effective at the 0.01 probability level in producing a sample with an easily removable silver skin than mechanical demucilaging with the Hess machine. Artificial drying produces a sample from which the silver skin can be more easily removed than natural drying at the 0.05 probability level. Furthermore, there was significance at the 0.01 probability level when the interaction between the two main effects of drying and demucilaging were considered. In considering the interaction of the two main effects it was found that natural fermentation combined with artificial (rotary-drier) drying produced the most favorable results. It was significantly greater than any of the other three possible combinations at the 0.01-percent probability level and there was no significant difference between the latter three. This lack of significance may be attributed, in part, to possible negative interaction between the two main effects, that is, in certain combinations the two main effects may have the effect of causing the silver skin to adhere tenaciously to the bean.


2004 ◽  
Vol 22 (SI - Chem. Reactions in Foods V) ◽  
pp. S22-S24 ◽  
Author(s):  
K. Bagdonaite ◽  
M. Murkovic

Four types of green coffee beans (Robusta and Arabica) were roasted in a laboratory roaster and in an oven. The samples were analysed for acrylamide using liquid chromatography with UV detection. Significant difference in acrylamide content was observed in different coffee types. Robusta coffee beans, roasted to different degrees of browning contained more acrylamide than Arabica varieties. Roasting time and temperature had a great influence on the acrylamide formation in coffee beans. Coffee beans roasted for longer time had less acrylamide. Additionally, coffee beans roasted at higher temperatures contained less acrylamide compared to those roasted at lower temperatures.


2021 ◽  
Author(s):  
Phanwimol Tanhan ◽  
Paphatsara Khunlert ◽  
Amnart Poapolathep ◽  
Saranya Poapolathep ◽  
Kanjana Imsilp

The study was conducted on 50 samples of coffee beans from various origins. The samples included green coffee beans, roasted beans, brew coffee drinks and coffee sludge. Three processes were used to prepare these samples: dried, semi-washed, and washed. Three synthetic pyrethroid insecticides and nine heavy metals were subsequently analyzed using modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) and acid digestion methods, respectively. The quantification of pyrethroids was performed by GC-µECD whereas those of metals were determined using flame atomic absorption spectrophotometer. According to the results, concentrations of both pyrethroids and heavy metals were predominantly found in green coffee beans except for Cr. Pyrethroid insecticides were not detectable in brew coffee drink and heavy metal concentrations were below the acceptable daily intake (ADI) level. Risk estimations for daily coffee intake using the health risk indices (HRIs) and target hazard quotients (THQs) of normal and the 97.5 percentile Thai consumers were less than 1. This indicated that the coffee drinks from studied samples could not cause potential health risk.


2019 ◽  
Author(s):  
Chem Int

Coriander (Coriandrum sativum L.) is one of the herbs which is used for medicinal and food purposes. In the present study the levels of selected metals in coriander leaves were determined in the samples collected from four different farmlands (Sebeta, Mekanisa, Holeta and Gefersa) in Ethiopia where its cultivation is common. The levels of metals were determined after digestion of samples with the mixture of 4 mL of HNO3 and 4 mL of HClO4 at 300 oC for 3:00 hours by flame atomic absorption spectrometry. The optimized wet digestion method for coriander leaves analysis was validated through the recovery experiment and a good percentage recovery was obtained (93.2-101%). The levels of metals were found in the range Ca, 2319–3503 mg/kg; Zn, 33.4–54.8 mg/kg and Cr, 5.55-9.86 mg/kg while the trace metals Cu, Ni, Cd and Pb were too low to be detected. The results indicated that Ethiopian coriander is a good source of essential metals and free from the toxic metals Pb and Cd. A statistical analysis of variance (ANOVA) at 95% confidence level indicated that there is significant difference (p < 0.05) in the levels of all detected metals between the four sample means. The Pearson correlation was used to predict the dependence of metal levels on one another. The levels of the metals determined in this study compared well with those reported for coriander leaves from some other parts of the world.


2021 ◽  
pp. 130504
Author(s):  
Fareeya Kulapichitr ◽  
Chaleeda Borompichaichartkul ◽  
Mingchih Fang ◽  
Inthawoot Suppavorasatit ◽  
Keith R. Cadwallader

2022 ◽  
pp. 101552
Author(s):  
Ammar Mohammed Ahmed Ali ◽  
Sakina Yagi ◽  
Ahmed A. Qahtan ◽  
Abdurrahman A. Alatar ◽  
Simone Angeloni ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document