PURPOSE: To provide powdered ptisan which can be served with easiness of tea-bag, by the vacuum drying of decocted barley water.

CONSTITUTION: Water (a) containing barley is boiled in a container 1 with a burner 2, and the decoction (a') ia spray-dried in a vacuum oven 3 to obtain the ptisan powder (a'''), which is packed in a bag 4. The pitsan powder (a''') is seasoned with sugar (b), etc. and packed in a bottle 6 or with a vacuum package 7. Steam generated at the initial stage of the boiling may be collected, condensed with a condenser 5, and extracted to obtain the decoction (a'). The decoction (a') may be cooled and freeze-dried in a vacuum chamber to obtain the powder. The waste of the decoction is useful as feeds or fertilizers.