Brewing unit

A method for preparing a beverage from a powdered product containing at least one ingredient with a brewing unit comprising

• a support structure comprising an inner cavity, and
• a dispensing assembly including
• a first assembly part configured as a drawer insertable into or extractable from a lower part of said inner cavity and comprising a receptacle adapted to receive said powdered product, and
• a second assembly part mounted to slide vertically within an upper part of said inner cavity, between a raised position, in which the second assembly part allows insertion or extraction of the first assembly part, and a lowered position, in which the second assembly part and the first assembly part are coupled to each other to define a brewing chamber therebetween,
• wherein within said first assembly part there is mounted to translate vertically a filtering element through which there is formed a dispensing duct, said filtering element defining a bottom surface of the receptacle and of the brewing chamber,
• wherein a brewing head adapted to inject water into the brewing chamber is carried by a lower end of the second assembly part, said brewing head defining a top surface of the brewing chamber and being provided with a radial sealing gasket configured to come in contact with a radially inner surface of the receptacle in the lowered position of the second assembly part, and
• wherein the second assembly part further comprises a plunger hydraulically operated and slidable within the upper part of said inner cavity, said plunger carrying the brewing head,
• the brewing unit further comprising
• springs interposed between the plunger and a hydraulic cylinder fixed to the support structure, said springs being adapted to bias the plunger toward a retracted position corresponding to the raised position of the second assembly part,
• said method comprising the following steps:
• a) with the first assembly part in an insertion end position, supplying cold water to the hydraulic cylinder to move the plunger of the second assembly part forward and bring the second assembly part to couple with the first assembly part,
• b1) through the plunger and the brewing head, supplying optionally a first quantity of heated water into the brewing chamber to wet the powdered product,
• b2) waiting optionally for a predetermined time interval,
• c) through the plunger and the brewing head, supplying a second quantity of heated water, greater than said first quantity, into the brewing chamber to prepare the beverage, and
• d) supplying optionally further cold water to the hydraulic cylinder to move the plunger further forward and to compress the used powdered product against the second assembly part.