الفهرس 
Introduction
As absorbency of reactantOnly 14 pages are availabe for public view
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Abstract
This investigation aimed to evaluate some chemical constituents of coffee such as moisture, lipids, protein, ash, carbohydrates, caffeine and polyphenols. Also, caffeine and polyphenols of coffee beans were determined as natural antioxidants. Residues of coffee brews were studied as a source for polyphenols. Effect of roasting and storage was also investigated. Green coffee bean was obtained from the market which represent sample no. 1, roasting process was carried out for the green sample, to obtain another 4 samples namely: very light, light, medium and dark roasted, by heating at 160oC for 1, 2, 3 and 5 hr., respectively. Last sample (Commercial roasted sample) was obtained from the green sample which roasted in the market by their own procedure summarized in the following points: 1- Moisture content as percentage was 11.516, 8.161, 3.846, 3.516, 2.154 and 1.634 for green and different roasted samples, respectively. Moisture content was affected with storage in different levels of decrease according to the period of storage. 2- Ash content was in the range 5.146 – 5.628 (as %), a decrease in the percentage of ash content was occurred as a result of storage. 3- Protein content (%) was 15.930 for green sample and 15.996, 16.188, 16.304, 17.961 and 16.835 for previous roasted samples, respectively. 4- Crude lipids were ranged between 13.907 – 16.670% for green and roasted samples. 5- Percentages of total soluble sugars were: 0.448, 0.455, 0.512, 0.605, 0.701 and 0.621 for green, very light roasted, light roasted, medium roasted, dark roasted and commercially roasted samples, respectively. While the percentages of reducing sugars were 0.096, 0.097, 0.094, 0.096, 0.091 and 0.085 for previous described samples. 6- Analysis for mineral contents revealed the presence of: sodium, potassium, calcium, magnesium, zinc, cupper, iron and manganese with different concentrations. 7- Green or roasted coffee contained terpenes, tannins, flavonoids, alkaloids, carbohydrates, phenolic glycosides, polyphenolic compounds and caffeine. 8- Caffeine was ranged between 1.467 mg/100 g for green coffee and 1.2 mg/100 g for roasted coffee. Minute decrease, in caffeine content, was observed during storage periods. 9- Roasting losses or dry matter losses were: 19.568, 13.234, 14.142, 14.449 and 16.658% for the very light, light, medium, dark and commercial roasted samples, respectively. 10- Polyphenols in green coffee were 80.111 as mg of Gallic acid/g., while their contents for the roasted samples were: 71.556, 70.778, 67.778, 64.556 and 71.336 since. Polyphenols content was affected by roasting. 11- Analysis by HPLC for polyphenols revealed the presence of 25 components, 14 as unknowns, and 11 as knowns namely: Catechin, P-hydroxy benzoic acid, Chlorogenic acid, Caffeinc acid, Syringic acid, Caffeine, Vanillic acid, P. coumaric acid, ferulic acid. Salicylic acid and Cinnamic acid, in green coffee beans. On the other hand 26 components were identified in light roasted sample, 11 as knowns as reported before, and the rest as unknowns, 27 and 25 components were identified as polyphenols for dark and commercial roasted samples, respectively. Chlorogenic acid was the main component in all samples. 12- Antioxidant capacity of caffeine extracts with (ABTS+) cation radical as percentage of inhibition was 77.34, 75.05, 72.95 and 72.00 for green, light roasted, dark roasted and commercial roasted samples, respectively. 13- Antioxidant capacity of polyphenols extracts with (ABTS+) cation radical as percentage of inhibition were 86.09, 82.67, 81.14 and 79.43 for mentioned samples. 14- Antioxidant capacity of Polyphenols of green beans > antioxidant capacity of light roasted > antioxidant capacity of drak roasted > antioxidant capacity of commercial roasted > antioxidant capacity of Caffeine of green coffee > antioxidant capacity of light roasted > antioxidant capacity of dark roasted > antioxidant capacity of commercial roasted coffee. 15- Caffeine, polyphenols and mixture of caffeine and polyphenols in the ratio of 1:1 w/w were added separately to crude sunflower oil in the concentrations of 1000, 3000 and 6000 ppm for keeping quality of oil from deterioration. Results indicated that polyphenols extract was stronger than the mixture and caffeine extracts i.e. polyphenols extracts > mixture > caffeine extracts. Also high concentration had stronger effect than the lower, for all extracts. 16- Reducing power of extracted caffeine as absorbency indicate that caffeine of green coffee have the highest reducing power. Caffeine of commercial roasted coffee have the lowest reducing power. 17- Reducing power of extracted polyphenols as absorbency revealed that the extract of green coffee have the highest reducing power. On the other hand, the polyphenols of commercial roasted coffee have the lowest reducing power, by means: Reducing power of polyphenols of green coffee > reducing power of light roasted > dark roasted > commercial roasted coffee. Also, reducing power of polyphenols > reducing power of caffeine, for all samples. 18- Acid value of extracted oil was 2.949, 3.262, 3.273, 3.534, 3.858 and 3.853 for green, very light, light, medium, dark and commercial roasted coffee. An increase in acid value was occurred as a results for storage. 19- Peroxide value was 1.231, 4.050, 5.553, 5.843, 6.025 and 1.430 for the extracted oil from green, very light, light, medium, dark and commercial roasted coffee. 20- Palmitic, stearic, oleic, linoleic, linolenic, arachidic acids were identified by GLC technique as components of extracted oil, as methyl esters, in different concentrations. 21- Percentage of green coffee residue and commercial roasted coffee residue was 92.258 and 80.989, respectively. While the total lipids, crude protein, caffeine and polyphenols in the residues of green coffee were: 10.00%, 11.320%, 1.041 mg/g, 59.937 mg/g and 6.974%, 10.063%, 0.407 mg/g and 29.800 mg/g, for the residues of roasted coffee, respectively. 22- Gallic acid, Protocatechoic, Pyrogalol, Catechin, Chlorogenic acid, Caffeic acid, Vanillic acid, Synergic acid, Caffeine, Ferulic, Coumarine, Cinnamic acid and Chrisin were identified as polyphenolic components of the residues of green coffee and/or roasted coffee, in different concentrations, when polyphenols were analysed by HPLC. 23- Antioxidant capacity of caffeine and polyphenols of green and roasted coffee residues by (ABTS+) cation radical was 27.86, 21.56 and 57.63, 45.80 as percentage of inhibition, respectively. 24- Reducing power of caffeine extracted from green or roasted coffee residues, identified as absorbency was, 0.314, 0.435, 0.620 and 0.115, 0.288, 0.395 for the concentrations 25, 50 and 75 mg/ml, respectively. 25- Reducing power of polyphenols extracted from green or roasted coffee residues, identified as absorbency, was 1.061, 1.240, 1.460 and 0.686, 0.833, 0.900 for the concentrations 25, 50 and 75 mg/ml. respectively. 26- Reducing power for caffeine and polyphenols extracted from green or commercial roasted coffee residues, estimated as milli-equivalents of ferrous was in the same line as optical density. 27- Phenolic compounds extracted from roasted coffee have stronger effect than caffeine extract, as antimicrobial. Caffeine and phenolic extracts were more effective on the growth of Fusarium oxysporum than Aspergillus niger . For yeasts, results exhibited that Candida albicans was more resistance than saccharomyces cervisiae towards both extracts.