Effect of extraction temperature on cream and extractability of black tea [Camellia sinensis (L.) O. Kuntze]

Tea cream and haze in black tea infusions increased with the rise in the tea extraction temperature. The temperature at which substances involved in cream and haze formation began to be extensively extracted into the tea infusion was between 50 and 60 degreesC. The tea cream particle volume concentration in infusions extracted at 50 degreesC or below formed less tea cream particles, and their particle sizes were larger and more heterogeneous than those extracted at 60 degreesC and second infusions extracted at 90 degreesC from the residual leaves that were previously extracted at 40-50 degreesC. High-performance liquid chromatography confirmed that constituents with pyrogallol groups are involved in tea creaming, and the effect of caffeine on tea cream and haze depends on whether these constituents are sufficiently present. The extractability of tea increased with the rise in extraction temperature. Two-stage extraction of tea in ready-to-drink tea processing and its effects on colorimetric indicators were also examined.