Impact of ultrasonic-assisted extraction on the chemical and sensory quality of tea infusion

The effects of ultrasonic-assisted extraction on the chemical and sensory quality of tea infusion were investigated. Ultrasonic-assisted extraction showed a better effect on the extraction efficiency of the main chemical components from tea at lower temperatures. The contents of tea polyphenols, amino acid and caffeine in tea infusions were more than those obtained by conventional extraction. Moreover, ultrasonic-assisted extraction inhibited the extraction of protein and pectin. The results also showed that ultrasonic-assisted extraction could increase the extraction yields of aroma components and glycosidic aroma precursors as well as changing the Owuor index of tea infusions. Organoleptic evaluation indicated that the sensory quality of tea infusion with ultrasonic-assisted extraction was better than that of tea infusion with conventional extraction. (c) 2005 Elsevier Ltd. All rights reserved.