Apparatus for aerating a pasty product and for mixing with another product

An apparatus for aerating a pasty product, the apparatus comprising:

• a housing extending in a longitudinal direction, the housing comprising an inlet for the pasty product to be aerated and an outlet for the aerated pasty product;
• within the housing, at least a first set of a rotor and a stator and a second set of a rotor and a stator, the at least each set of the rotor and the stator having complementary toothed rims oppositely orientated in the longitudinal direction;
• a drive shaft, the rotors of the at least each set of the rotor and the stator being coupled to the drive shaft;
• a gas injector for injecting, upstream of the first set of the rotor and the stator, a gas into the pasty product to be aerated;
• an intermediate mixing chamber provided in the housing between the first and the second sets of the rotor and the stator;
• and
• a secondary product introduction member which protrudes into the intermediate mixing chamber so as to issue into the intermediate mixing chamber.