Determination of Caffeine Content and Antioxidant Activity of Coffee

Belete Tewabe Gebeyehu; Solomon Libsu Bikila

doi:doi:10.11648/j.ajac.20150302.16

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Determination of Caffeine Content and Antioxidant Activity of Coffee

Belete Tewabe Gebeyehu, Solomon Libsu Bikila

Published in American Journal of Applied Chemistry (Volume 3, Issue 2)

Received: 13 March 2015 Accepted: 25 March 2015 Published: 31 March 2015

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Abstract

Attempt has been made to look into caffeine contents and antioxidant activity of coffee grown at Wembera, Goncha, Zegie, and Burie localities of North-West Ethiopia. The caffeine content of the extracts in % w/w has been found to be 1.53 ± 0.003 for Wembera coffee, 1.41 ± 0.040 for Goncha coffee, 1.29 ± 0.033 for Zegie coffee and 0.97 ± 0.049 for Burie coffee. The antioxidant activities of the coffee extracts were measured by using ferric reducing power assay and Rancimat assay. Ferric reducing power assay was used to measure the total antioxidant power of water soluble components of coffee and is expressed as ascorbic acid equivalent antioxidant capacity in milligram per gram of the dried coffee samples. The ferric reducing power values of the extracts were 9.532 ± 0.201, 9.159 ± 0.441, 8.955 ± 0.180, 6.751 ± 0.284 for Wembera, Burie, Goncha and Zegie coffees, respectively. The Rancimat assay was also used to measure antioxidant activity of lipid soluble portions of coffee extracts using sunflower oil as the oxidizable substrate. It was found that all the coffee extracts improved the oxidative stability of sunflower oil. The protection factors were 1.36 ± 0.027, 1.31 ± 0.027, 1.26 ± 0.069 and 1.17 ± 0.015 for Wembera, Burie, Goncha and Zegie coffees respectively. Based on these results, it is suggested that Wembera coffee has the higher caffeine content and antioxidant activities than Burie, Goncha and Zegie coffee varieties.

Published in	American Journal of Applied Chemistry (Volume 3, Issue 2)
DOI	10.11648/j.ajac.20150302.16
Page(s)	69-76
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2015. Published by Science Publishing Group

Keywords

Coffee, Caffeine, Antioxidant Activity, Ferric Reducing Power, Rancimat Assay

References

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Belete Tewabe Gebeyehu, Solomon Libsu Bikila. (2015). Determination of Caffeine Content and Antioxidant Activity of Coffee. American Journal of Applied Chemistry, 3(2), 69-76. https://doi.org/10.11648/j.ajac.20150302.16

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Belete Tewabe Gebeyehu; Solomon Libsu Bikila. Determination of Caffeine Content and Antioxidant Activity of Coffee. Am. J. Appl. Chem. 2015, 3(2), 69-76. doi: 10.11648/j.ajac.20150302.16

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Belete Tewabe Gebeyehu, Solomon Libsu Bikila. Determination of Caffeine Content and Antioxidant Activity of Coffee. Am J Appl Chem. 2015;3(2):69-76. doi: 10.11648/j.ajac.20150302.16

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@article{10.11648/j.ajac.20150302.16,
  author = {Belete Tewabe Gebeyehu and Solomon Libsu Bikila},
  title = {Determination of Caffeine Content and Antioxidant Activity of Coffee},
  journal = {American Journal of Applied Chemistry},
  volume = {3},
  number = {2},
  pages = {69-76},
  doi = {10.11648/j.ajac.20150302.16},
  url = {https://doi.org/10.11648/j.ajac.20150302.16},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajac.20150302.16},
  abstract = {Attempt has been made to look into caffeine contents and antioxidant activity of coffee grown at Wembera, Goncha, Zegie, and Burie localities of North-West Ethiopia. The caffeine content of the extracts in % w/w has been found to be 1.53 ± 0.003 for Wembera coffee, 1.41 ± 0.040 for Goncha coffee, 1.29 ± 0.033 for Zegie coffee and 0.97 ± 0.049 for Burie coffee. The antioxidant activities of the coffee extracts were measured by using ferric reducing power assay and Rancimat assay. Ferric reducing power assay was used to measure the total antioxidant power of water soluble components of coffee and is expressed as ascorbic acid equivalent antioxidant capacity in milligram per gram of the dried coffee samples. The ferric reducing power values of the extracts were 9.532 ± 0.201, 9.159 ± 0.441, 8.955 ± 0.180, 6.751 ± 0.284 for Wembera, Burie, Goncha and Zegie coffees, respectively. The Rancimat assay was also used to measure antioxidant activity of lipid soluble portions of coffee extracts using sunflower oil as the oxidizable substrate. It was found that all the coffee extracts improved the oxidative stability of sunflower oil. The protection factors were 1.36 ± 0.027, 1.31 ± 0.027, 1.26 ± 0.069 and 1.17 ± 0.015 for Wembera, Burie, Goncha and Zegie coffees respectively. Based on these results, it is suggested that Wembera coffee has the higher caffeine content and antioxidant activities than Burie, Goncha and Zegie coffee varieties.},
 year = {2015}
}

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TY  - JOUR
T1  - Determination of Caffeine Content and Antioxidant Activity of Coffee
AU  - Belete Tewabe Gebeyehu
AU  - Solomon Libsu Bikila
Y1  - 2015/03/31
PY  - 2015
N1  - https://doi.org/10.11648/j.ajac.20150302.16
DO  - 10.11648/j.ajac.20150302.16
T2  - American Journal of Applied Chemistry
JF  - American Journal of Applied Chemistry
JO  - American Journal of Applied Chemistry
SP  - 69
EP  - 76
PB  - Science Publishing Group
SN  - 2330-8745
UR  - https://doi.org/10.11648/j.ajac.20150302.16
AB  - Attempt has been made to look into caffeine contents and antioxidant activity of coffee grown at Wembera, Goncha, Zegie, and Burie localities of North-West Ethiopia. The caffeine content of the extracts in % w/w has been found to be 1.53 ± 0.003 for Wembera coffee, 1.41 ± 0.040 for Goncha coffee, 1.29 ± 0.033 for Zegie coffee and 0.97 ± 0.049 for Burie coffee. The antioxidant activities of the coffee extracts were measured by using ferric reducing power assay and Rancimat assay. Ferric reducing power assay was used to measure the total antioxidant power of water soluble components of coffee and is expressed as ascorbic acid equivalent antioxidant capacity in milligram per gram of the dried coffee samples. The ferric reducing power values of the extracts were 9.532 ± 0.201, 9.159 ± 0.441, 8.955 ± 0.180, 6.751 ± 0.284 for Wembera, Burie, Goncha and Zegie coffees, respectively. The Rancimat assay was also used to measure antioxidant activity of lipid soluble portions of coffee extracts using sunflower oil as the oxidizable substrate. It was found that all the coffee extracts improved the oxidative stability of sunflower oil. The protection factors were 1.36 ± 0.027, 1.31 ± 0.027, 1.26 ± 0.069 and 1.17 ± 0.015 for Wembera, Burie, Goncha and Zegie coffees respectively. Based on these results, it is suggested that Wembera coffee has the higher caffeine content and antioxidant activities than Burie, Goncha and Zegie coffee varieties.
VL  - 3
IS  - 2
ER  -

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Author Information

Belete Tewabe Gebeyehu

Department of Chemistry, Natural and computational Science College, Debre Birhan University, Debre Birhan, Ethiopia
Solomon Libsu Bikila

Department of Chemistry, Science College, Bahir Dar University, Bahir Dar, Ethiopia

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Belete Tewabe Gebeyehu, Solomon Libsu Bikila. (2015). Determination of Caffeine Content and Antioxidant Activity of Coffee. American Journal of Applied Chemistry, 3(2), 69-76. https://doi.org/10.11648/j.ajac.20150302.16

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ACS Style

Belete Tewabe Gebeyehu; Solomon Libsu Bikila. Determination of Caffeine Content and Antioxidant Activity of Coffee. Am. J. Appl. Chem. 2015, 3(2), 69-76. doi: 10.11648/j.ajac.20150302.16

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AMA Style

Belete Tewabe Gebeyehu, Solomon Libsu Bikila. Determination of Caffeine Content and Antioxidant Activity of Coffee. Am J Appl Chem. 2015;3(2):69-76. doi: 10.11648/j.ajac.20150302.16

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@article{10.11648/j.ajac.20150302.16,
  author = {Belete Tewabe Gebeyehu and Solomon Libsu Bikila},
  title = {Determination of Caffeine Content and Antioxidant Activity of Coffee},
  journal = {American Journal of Applied Chemistry},
  volume = {3},
  number = {2},
  pages = {69-76},
  doi = {10.11648/j.ajac.20150302.16},
  url = {https://doi.org/10.11648/j.ajac.20150302.16},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajac.20150302.16},
  abstract = {Attempt has been made to look into caffeine contents and antioxidant activity of coffee grown at Wembera, Goncha, Zegie, and Burie localities of North-West Ethiopia. The caffeine content of the extracts in % w/w has been found to be 1.53 ± 0.003 for Wembera coffee, 1.41 ± 0.040 for Goncha coffee, 1.29 ± 0.033 for Zegie coffee and 0.97 ± 0.049 for Burie coffee. The antioxidant activities of the coffee extracts were measured by using ferric reducing power assay and Rancimat assay. Ferric reducing power assay was used to measure the total antioxidant power of water soluble components of coffee and is expressed as ascorbic acid equivalent antioxidant capacity in milligram per gram of the dried coffee samples. The ferric reducing power values of the extracts were 9.532 ± 0.201, 9.159 ± 0.441, 8.955 ± 0.180, 6.751 ± 0.284 for Wembera, Burie, Goncha and Zegie coffees, respectively. The Rancimat assay was also used to measure antioxidant activity of lipid soluble portions of coffee extracts using sunflower oil as the oxidizable substrate. It was found that all the coffee extracts improved the oxidative stability of sunflower oil. The protection factors were 1.36 ± 0.027, 1.31 ± 0.027, 1.26 ± 0.069 and 1.17 ± 0.015 for Wembera, Burie, Goncha and Zegie coffees respectively. Based on these results, it is suggested that Wembera coffee has the higher caffeine content and antioxidant activities than Burie, Goncha and Zegie coffee varieties.},
 year = {2015}
}

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TY  - JOUR
T1  - Determination of Caffeine Content and Antioxidant Activity of Coffee
AU  - Belete Tewabe Gebeyehu
AU  - Solomon Libsu Bikila
Y1  - 2015/03/31
PY  - 2015
N1  - https://doi.org/10.11648/j.ajac.20150302.16
DO  - 10.11648/j.ajac.20150302.16
T2  - American Journal of Applied Chemistry
JF  - American Journal of Applied Chemistry
JO  - American Journal of Applied Chemistry
SP  - 69
EP  - 76
PB  - Science Publishing Group
SN  - 2330-8745
UR  - https://doi.org/10.11648/j.ajac.20150302.16
AB  - Attempt has been made to look into caffeine contents and antioxidant activity of coffee grown at Wembera, Goncha, Zegie, and Burie localities of North-West Ethiopia. The caffeine content of the extracts in % w/w has been found to be 1.53 ± 0.003 for Wembera coffee, 1.41 ± 0.040 for Goncha coffee, 1.29 ± 0.033 for Zegie coffee and 0.97 ± 0.049 for Burie coffee. The antioxidant activities of the coffee extracts were measured by using ferric reducing power assay and Rancimat assay. Ferric reducing power assay was used to measure the total antioxidant power of water soluble components of coffee and is expressed as ascorbic acid equivalent antioxidant capacity in milligram per gram of the dried coffee samples. The ferric reducing power values of the extracts were 9.532 ± 0.201, 9.159 ± 0.441, 8.955 ± 0.180, 6.751 ± 0.284 for Wembera, Burie, Goncha and Zegie coffees, respectively. The Rancimat assay was also used to measure antioxidant activity of lipid soluble portions of coffee extracts using sunflower oil as the oxidizable substrate. It was found that all the coffee extracts improved the oxidative stability of sunflower oil. The protection factors were 1.36 ± 0.027, 1.31 ± 0.027, 1.26 ± 0.069 and 1.17 ± 0.015 for Wembera, Burie, Goncha and Zegie coffees respectively. Based on these results, it is suggested that Wembera coffee has the higher caffeine content and antioxidant activities than Burie, Goncha and Zegie coffee varieties.
VL  - 3
IS  - 2
ER  -

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