Effect of Infusion Time and Temperature on Decaffeination of Tea Using Liquid–Liquid Extraction Technique

Abstract

Pure caffeine was dissolved in four different solvents, i.e., distilled water, ethyl acetate, chloroform and dichloromethane; further, molar decadic absorption coefficient of each solvent was determined with the help of Beer-Lambert law. It was observed that dichloromethane was the best for decaffeination as compared with the other three solvents (i.e., distilled water, chloroform and ethyl acetate). Caffeine was extracted using dichloromethane from five famous tea brands, namely Alokozay, Lipton, Tapal, Tetley and PG TIPS. The amount of extracted caffeine was quantified by employing UV-vis spectrophotometric technique. The concentration of the caffeine in the tea solution was determined at different brewing time (2, 5, 10, 15, 20, 25 and 30 min) and temperature (90 and 30C). The caffeine contents in the commercial brands (i.e., Alokozay, Lipton, Tapal, Tetley and PG TIPS) were found in the range between 1 and 5%.

Valorization of Expired Energy Drinks by Designed and Integrated Ionic Liquid-Based Aqueous Biphasic Systems

“…Several methods, including liquid–liquid extraction, nanofiltration, and solid-phase extraction, have been reported for the recovery of target compounds from diet samples and beverages. In addition to the extraction step, separation and purification processes are needed, which may comprise numerous drawbacks, including high energy and chemical consumption. , Furthermore, most of these methods are time-consuming and labor intensive and use volatile organic solvents, contributing to a relevant environmental impact.…”

“…Thus, the recovery and reuse of value-added and bioactive compounds from discharged energy drinks has a relevant environmental and economic influence on this market sector that registered global sales over €38 billion in 2015 and is expected to reach €53.4 billion in 2020. 7 Several methods, including liquid−liquid extraction, 8 nanofiltration, 9 and solid-phase extraction, 10 have been reported for the recovery of target compounds from diet samples and beverages. In addition to the extraction step, separation and purification processes are needed, which may comprise numerous drawbacks, including high energy and chemical consumption.…”

UV-Vis spectral fingerprinting and chemometric method applied to the evaluation of Camellia sinensis leaves from different harvests

“…These results are conrmed by literature studies testing various solvents which show that dichloromethane is more efficient for extracting caffeine. [53][54][55] Moreover, it is also used as a solvent in the decaffeination of tea. 54 As for caffeine, the linear dichloromethane coefficients (d) were highest for the Phya special cubic model.…”

A Conceptual Demonstration of Decaffeination via Nanofiltration

“…Roasted coffee powder of 50 g was inserted into an envelope made of nonwoven fabric and stirred with 1 L of distilled water at 70 °C for 1 h to prepare the coffee solution for the decaffeination study using NF hollow fiber membranes. Because of the complexity of compounds present in the coffee solution that will affect the absorbance of UV/vis analyses, solvent extraction was performed using ethyl acetate to extract the caffeine from the coffee solution to analyze and quantify the caffeine content . An aliquot of 10 mL was first taken from each sample and mixed with 5 mL of ethyl acetate.…”

“…Because of the complexity of compounds present in the coffee solution that will affect the absorbance of UV/vis analyses, solvent extraction was performed using ethyl acetate to extract the caffeine from the coffee solution to analyze and quantify the caffeine content. 23 An aliquot of 10 mL was first taken from each sample and mixed with 5 mL of ethyl acetate. The mixture was agitated and left stagnant until the formation of binary layers.…”