A brewing unit (1) comprises a supporting structure (3) and a brewing chamber (7) supported by the supporting structure (3). The brewing chamber (7) comprises a first brewing chamber portion (9) and asecond brewing chamber portion (11), movable one with respect to the other along an opening and closing direction (F) from an open position to a closed position and vice-versa. An actuation mechanism(15) is provided for closing and opening the brewing chamber (7). The brewing unit further comprises a capsule insertion aperture (5) and a capsule guiding arrangement (33) between the capsule insertion aperture (5) and a capsule intermediate position. The capsule guiding arrangement (33) comprises a first component (35), stationarily mounted on the supporting structure (3), and a second component (37), pivotally mounted on the stationary structure (3) around a pivoting axis (37A) approximately orthogonal the opening and closing direction (F). The first component (35) of the capsule guiding arrangement (33) is comprised of a first capsule contacting surface (39A), configured and arranged for engaging a top surface (Cs) of a capsule (C) which is introduced in the brewing unit (1). The second component (37) of the capsule guiding arrangement (33) is comprised of second capsule contacting surfaces (51A), configured and arranged for engaging a capsule rim (R) surrounding the capsule (C),on a rim surface opposite said top surface (Cs).