Designed Polar Cosolvent-Modified Supercritical CO2 Removing Caffeine from and Retaining Catechins in Green Tea Powder Using Response Surface Methodology

• Published in: Journal of agricultural and food chemistry 2007-10, Vol.55 (22), p.9014-9020
• Main Authors: Huang, Kuo-Jong, Wu, Jia-Jiuan, Chiu, Yung-Ho, Lai, Cheng-Yung, Chang, Chieh-Ming J
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biotechnology; caffeine; Caffeine - isolation & purification; Camellia sinensis; carbon dioxide; Catechin - analysis; catechins; Chromatography, Supercritical Fluid - instrumentation; Chromatography, Supercritical Fluid - methods; Coffee, tea and other stimulative beverage industries; concentration factor; cosolvent addition; extraction efficiency; flavonols; food analysis; food composition; Food engineering; Food industries; Food Preservation; Fundamental and applied biological sciences. Psychology; General aspects; green tea; green tea powder; polar compounds; polar cosolvent-modified supercritical carbon dioxide; powders; response surface methodology; Solvents; Supercritical carbon dioxide decaffeination; supercritical fluid extraction; Tea - chemistry
• ISSN: 0021-8561; 1520-5118
• DOI: 10.1021/jf071161q

This study examines cosolvent-modified supercritical carbon dioxide (SC-CO2) to remove caffeine from and to retain catechins in green tea powder. The response surface method was adopted to determine the optimal operation conditions in terms of the extraction efficiencies and concentration factors of caffeine and catechins during the extractions. When SC-CO2 was used at 333 K and 300 bar, 91.5% of the caffeine was removed and 80.8% of catechins were retained in the tea: 3600 g of carbon dioxide was used in the extraction of 4 g of tea soaked with 1 g of water. Under the same extraction conditions, 10 g of water was added to