A machine (1)for homogenising a food substance has: a container (10) with a side wall (11) and a bottom wall (12) delimiting a cavity (10'); an impeller (30) with an impelling member (31) forming an impelling surface (31',31'',31''') that is drivable in rotation (r) about a central axial direction (30') of the impelling surface (31',31'',31''') for imparting a mechanical effect to the food substance; and a module (20) which has a housing means (22') that contains an inner chamber (22,22a) and that delimits a seat (21) for the container (10), the chamber (22,22a) containing an electric motor (24). The electric motor (24) has an output drive axis (24') with a driver device (24'') configured to drive a follower device (35) of the impeller (30). The driver device (24'') and the follower device (35) are magnetically coupled through a sidewall (11) and/or bottom wall (12) of the container (10). The driver device (24'') comprises a ferromagnetic or magnetic field-generating element (24a) that is arranged to be magnetically coupled to a corresponding ferromagnetic or magnetic field-generating element (36) of the follower device (35).The follower device (35) extends over a predominant part of the bottom wall (12) of the container (10) or across a substantial part of the wall (12) along a diameter thereof. The driver device (24) extends over a predominant part of a bottom part of the seat (21) or across a substantial part of the bottom part of the seat (21) along a diameter thereof. The ferromagnetic and magnetic field generating elements (24a,36) are positioned at extremal or peripheral parts of the follower device (35) and of the driver device (24'').