Decaffeination of beverages using natural adsorbent

Abstract

In recent years, the demand for beverages with lower caffeine concentrations has been expanding. However, traditional decaffeination technologies for tea and coffee not only remove caffeine, but also reduce the active components responsible for beverage flavor and quality. In this study, we investigated the selectivity and versatility of decaffeination by montmorillonite (MMT) in beverages. MMT adsorbed caffeine from tea and coffee extracts more selectively than activated carbon (AC). Optimization of the contact conditions enabled stable decaffeination and prevented elution of Fe ions from MMT, which causes discoloration of tea beverages. MMT exhibited similar caffeine adsorption properties with various types of tea extracts and coffee extracts. In addition, ion-exchanged MMTs, which also removed caffeine, improved the appearance quality of decaffeinated beverages. Overall, our findings suggest that MMTis a useful adsorbent for producing high-quality decaffeinated beverages. Specifically, decaffeinated tea beverages treated with MMThave been commercially available since 2014 from Kirin Beverage Company Ltd.