High Pressure Liquid Chromatographic Determination of Theobromine and Caffeine in Cocoa and Chocolate Products: Collaborative Study
Abstract
Four duplicate samples of cocoa-containing materials, a practice sample, and standards were submitted to the collaborators for theobromine and caffeine analysis by HPLC. In the method the samples are defatted with petroleum ether, and dried. The fat-free residue is then extracted with water and an aliquot is injected into the chromatograph. Compounds are quantitated by comparison with internal or external standards, either by peak height or peak area. Results for all the analyses showed that few of the values were more than 2 standard deviations from the mean. The method has been adopted as official first action.
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Aortic PWV is an independent risk factor for total and cardiovascular mortality.
“Epidemiological data now show that PWV is an independent risk factor for total and cardiovascular mortality. 21,23”
From Acute Effect of Caffeine on Arterial Stiffness and Aortic Pressure Waveform (2001) · cites this paper as [23]
The caffeine content of the 250 mL coffee was 150 ± 5 mg for caffeinated and <2 mg for decaffeinated.
“The caffeine content of the 250 mL coffee determined by high-pressure liquid chromatography 23 was 150 6 5 and , 2 mg for caffeinated and decaffeinated coffee, respectively.”
From Acute Effect of Caffeine on Arterial Stiffness and Aortic Pressure Waveform (2001) · cites this paper as [23]
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Acute Effect of Caffeine on Arterial Stiffness and Aortic Pressure Waveform
Mahmud, A., & Feely, J. (2001) · Hypertension · doi:10.1161/01.hyp.38.2.227 · Cited by 192 · see citing works
- Authors
- kreiser, W. R., Martin, R. A., Collaborators:, Bigornia, R., Bond, R., Cummings, L. J., Teja, E. D. L., DeVries, J. W., Erwin, R. E., Heroff, J. C., Levi, C., Maglone, M., Schumacher, D., & Snyder, K.
- Affiliations
- Hershey (United States) (US)
- Venue
- Journal of AOAC INTERNATIONAL
- Publisher
- Oxford University Press (OUP)
- Published
- 1980-05-01
- Volume
- 63
- Issue
- 3
- Pages
- 591-594
- ISSN
- 0004-5756 (ISSN-L)
- OpenAlex
- W2398296689
- Cited by
- 9
- References
- 0
- Citations by year
- 2017: 1
- FWCI
- 1.40
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model (vor)
- Locations
- Journal of AOAC INTERNATIONAL (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Life Sciences › Agricultural and Biological Sciences › Food Science › Food Chemistry and Fat Analysis
- Physical Sciences › Chemistry › Spectroscopy › Analytical Chemistry and Chromatography
- Physical Sciences › Chemistry › Analytical Chemistry › Analytical Methods in Pharmaceuticals
- Keywords
- theobromine, caffeine, Theobroma cacao, chocolate, caffeine determination, method validation, collaborative study, official methods
- MeSH terms
- Cacao, Caffeine, Chromatography, High Pressure Liquid, Quality Control, Theobromine
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