PURPOSE: To obtain a coffee machine which prevents coffee powder from being oxidized by removing impurities contained in the coffee powder, such as grain hide and embryo powder, and cooling at the same time, providing less astringent, clear, aromatic and flavorous, purely albuminous coffee powder which can be stockpiled.

CONSTITUTION: A net cylinder (1) to which being supporting grooved rings 1', 1", a screen cylinder (1) and a ring gear (2) at the bottom side are attached, a small gear 5" which transmits rotation to a large gear 8' and a fan blade 6' which discharges grain hide powder and cools coffee powder having friction heat are fitted to a main spindle 4' which rotates the net cylinder (1). The spindle 7' of the large gear 8' is combined with a rotation unit (2) having a deformed gear 9' which induces sieving. A square hole 14 through which a embryo powder receiving box 13 with a brush is drawn in and out and a round hole 15 through which grain hide powder is discharged are formed in the lower part of a storage case (3) and a grain hide powder collection bag 17 is fitted outside.