Studies on the Instant Tea (Preliminary Report)

Abstract

To produce an instant tea, the following three processes were preliminarily studied.1. Extracting processFor applying a freezing concentration method in the second process, some concentrated extract had to be obtained in the first step.After trying several extracting methods, an extract having desirable concentration (10°Brix) could be obtained by modifying a batch countercurrent multiple contact method.2. Concentrating processTo decide the optimum density of the extract for freezing concentration, the original extract (10°Brix) and diluted extracts (5-7°Brix) were freezed in an icecream freezer and eliminated the ice crystal by centrifugation. The extract having over 8°Brix concentration was succeeded to be condensed by freezing and after two or three succesive treatments the starting extract (10°Brix) could be condensed up to 30-45°Brix.3. Drying processThe concentrated extract (30-45°Brix) was spread as even as possible 2mm. layer on stainless steel pans and heated at 80°C. under reduced pressure of 10-15mm. Hg.After 2.5-hours heating and then 0.5-hours cooling, well puffed dry powder was obtained. This product was very easily soluble in water and had good taste but less flavor.