Pre-drying and mechanical agitation device for the production of pasta comprising: - a containment structure, provided with an inlet opening and an outlet opening for pasta; - agitation and transport means, suitable for mechanically agitating pasta, transporting it at the same time from said inlet opening to said outlet opening; - heating means, suitable for heating an air flow that passes through them; - ventilation means, suitable for generating one or more air flows which pass through said heating means and said agitation and transport means, and then, at least in part, return cyclically in said ventilation means, wherein said ventilation means comprise a delivery region, from which said one or more air flows exit, and a suction region, through which at least part of said one or more air flows cyclically re-enters said ventilation means; characterized in that - suction and expulsion means of the air contained in said support structure and/or of the air exited from said outlet opening; - selective introduction means of air from the outside to the inside of said containment structure, through said inlet opening, configured to define an at least partial barrier to the entry of further air, excluding the one introduced by said selective introduction means themselves, through said inlet opening; - a bypass conduit which puts said delivery region of said ventilation means in fluid communication with said inlet opening, bypassing said agitation and transport means and said heating means, wherein said bypass conduit is defined between an internal surface of said containment structure and a wall of a containment case, internal to said containment structure, which at least partially contains said agitation and transport means and said heating means. - a containment structure, provided with an inlet opening and an outlet opening for pasta; - agitation and transport means, suitable for mechanically agitating pasta, transporting it at the same time from said inlet opening to said outlet opening; - heating means, suitable for heating an air flow that passes through them; - ventilation means, suitable for generating one or more air flows which pass through said heating means and said agitation and transport means, and then, at least in part, return cyclically in said ventilation means, wherein said ventilation means comprise a delivery region, from which said one or more air flows exit, and a suction region, through which at least part of said one or more air flows cyclically re-enters said ventilation means; characterized in that - suction and expulsion means of the air contained in said support structure and/or of the air exited from said outlet opening; - selective introduction means of air from the outside to the inside of said containment structure, through said inlet opening, configured to define an at least partial barrier to the entry of further air, excluding the one introduced by said selective introduction means themselves, through said inlet opening; - a bypass conduit which puts said delivery region of said ventilation means in fluid communication with said inlet opening, bypassing said agitation and transport means and said heating means, wherein