Effect of cosolvents (ethyl lactate, ethyl acetate and ethanol) on the supercritical CO<inf>2</inf> extraction of caffeine from green tea

This paper reports experimental data to analyze the effect of different green cosolvents, namely ethyl lactate, ethyl acetate and ethanol, on the supercritical carbon dioxide (SCCO2) extraction of caffeine from green tea leaves. The experiments were carried out in a pilot-scale plant using two diffe...

Descripción completa

Detalles Bibliográficos
Autores: Villanueva Bermejo, David, Ibáñez, Elena, Reglero Rada, Guillermo J., Fornari Reale, Tiziana
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universidad Autónoma de Madrid
Repositorio:Biblos-e Archivo. Repositorio Institucional de la UAM
Idioma:inglés
OAI Identifier:oai:repositorio.uam.es:10486/710330
Acceso en línea:http://hdl.handle.net/10486/710330
https://dx.doi.org/10.1016/j.supflu.2015.07.008
Access Level:acceso abierto
Palabra clave:Caffeine
Cosolvent
Ethyl lactate
Green tea
Supercritical fluid extraction
Física
Química
Descripción
Sumario:This paper reports experimental data to analyze the effect of different green cosolvents, namely ethyl lactate, ethyl acetate and ethanol, on the supercritical carbon dioxide (SCCO2) extraction of caffeine from green tea leaves. The experiments were carried out in a pilot-scale plant using two different approaches: a static procedure in which the cosolvent was introduced in the extraction cell soaking the vegetal material and then SCCO2 was pumped, and a dynamic assay in which the cosolvent was pumped and mixed with SCCO2 before introduction into the extraction cell. The overall caffeine recovery from plant matrix was determined for all experiments at the same extraction conditions (30 MPa and 343 K). Additionally, the overall extraction curves of the static experiments were determined at the same process conditions, and the mass transfer model of Sovová was utilized to adjust the kinetic data and to determine the mass transfer coefficients. The highest caffeine yield was obtained with ethyl lactate in both static and dynamic extractions (13.0 and 14.2 mg/g of tea, respectively), followed by ethanol (10.8 mg/g with the static method and 8.8 mg/g with the dynamic method). The yield obtained with ethyl acetate in both extraction approaches was lower than 7 mg/g. These data reinforce previous results obtained by the authors regarding the competence of ethyl lactate in the extraction of caffeine from natural materials