Extraction of methylxanthines from guaraná seeds, maté leaves, and cocoa beans using supercritical carbon dioxide and ethanol

Journal
Journal of agricultural and food chemistry  
Volume
50
Issue
17
Start Page
4820
End Page
4826
Citation
Journal of Agricultural and Food Chemistry 50 (17): 4820-4826 (2002-08-14)
Publisher DOI
10.1021/jf020128v
Scopus ID
2-s2.0-0037077367
PubMed ID
12166966
Publisher
ACS Publications
New experimental data on the extraction of caffeine from guaraná seeds and maté tea leaves, and theobromine from cocoa beans, with supercritical CO2 were obtained using a high-pressure extraction apparatus. The effect of the addition of ethanol to carbon dioxide on the extraction efficiency was also investigated. Caffeine extraction yields of 98% of the initial caffeine content in both wet ground guaraná seeds and maté tea leaves were obtained. Extractions of caffeine from guaraná seeds and maté tea leaves also exhibited a retrograde behavior for the two temperatures considered in this work. In the removal of theobromine from cocoa beans, a much smaller extraction yield was obtained with longer extraction periods and consequently larger solvent requirements. The results of this study confirm the higher selectivity of CO2 for caffeine in comparison with that for theobromine, and also the influence of other components in each particular natural product on the extraction of methylxanthines. The effect of the addition of ethanol to carbon dioxide on the extraction of methylxanthines was significant, particularly in the extraction of theobromine from cocoa beans. In general, the use of ethanol results in lower solvent and energy requirements and thereby improved extraction efficiency.
Subjects
Caffeine
Cocoa beans
Guaraná seeds
Maté leaves
Theobromine
DDC Class
540: Chemie
600: Technik