Effects of processing parameters on the caffeine extraction yield during decaffeination of black tea using pilot-scale supercritical carbon dioxide extraction technique

Abstract

In this pilot-scale study supercritical carbon dioxide (SCCO) extraction technique was used for decaffeination of black tea. Pressure (250, 375, 500 bar), extraction time (60, 180, 300 min), temperature (55, 62.5, 70 °C), CO flow rate (1, 2, 3 L/min) and modifier quantity (0, 2.5, 5 mol%) were selected as extraction parameters. Three-level and five-factor response surface methodology experimental design with a Box-Behnken type was employed to generate 46 different processing conditions. 100% of caffeine from black tea was removed under two different extraction conditions; one of which was consist of 375 bar pressure, 62.5 °C temperature, 300 min extraction time, 2 L/min CO flow rate and 5 mol% modifier concentration and the other was composed of same temperature, pressure and extraction time conditions with 3 L/min CO flow rate and 2.5 mol% modifier concentration. Results showed that extraction time, pressure, CO flow rate and modifier quantity had great impact on decaffeination yield.

Recent advances in carbon dioxide utilization

“…Important applications of SFE technology include the extraction of oils and fat fractions [107][108][109][110][111], lipids and cholesterol [112,113], natural colors [114], antioxidants [115,116], and hops [117,118], and decaffeination of tea and coffee [119][120][121]. A number of essential oils (EOs) are widely used in foods or cosmetics.…”

Supercritical fluid extraction–supercritical fluid chromatography of saliva: Single‐quadrupole mass spectrometry monitoring of caffeine for gastric emptying studies†

“…The literature is rich in reports concerning the solubility of caffeine in supercritical CO 2 [67][68][69][70][71][72], including the original proof-of-concept for online (nonquantitative) SFE-SFC by Sugiyama et al [73]. When working with solid matrices (e.g., coffee beans) and high analyte concentrations such as 0.7-1.6% (m/m) in the case of Coffea arabica [74], recovery correlates positively with residual moisture (ranging from 0 to 20%), pressure (100-200 bar), and total extraction time (up to hours).…”

Determining the Efficiency and Yield of Caffeine Extraction for Robusta and Arabica Coffee Beans

“…This investigation compares the caffeine content in the arabica coffee beans from Costco to the caffeine content of robusta and liberica coffee beans bought from other sources. The extraction process took place under high pressures as this is extremely inefficient for extracting caffeine from coffee [4]. Lastly, IR spectrometer, UVvis spectrum, and computation via Avogradro's systems were utilized to determine the identity of the substance.…”