Method for producing sterile receptacles, comprising the steps of: - obtaining parisons by melting and moulding granules of thermoplastic material in a moulding unit for moulding parisons, each of said parisons having a tubular body and a neck with an annular protrusion called bague, the parisons leaving the moulding unit with the tubular body at a temperature above 100°C and the neck being cooled so as to have a temperature between 20°C and 40°C, this creating a temperature imbalance between the neck and the tubular body, which temperature imbalance generates an uncontrolled thermal profile which extends down below the bague; - sterilizing the moulded parisons; - submitting the moulded parisons to thermal conditioning in a transferring unit comprising a star-wheel having a plurality of supporting stations for supporting the parisons by their neck, in each supporting station being arranged one thermal conditioning device configured to heat a tubular body of said parisons so that said parisons leaving the transferring unit have a predefined thermal profile adapted to allow forming by stretch-blowing; - obtaining the receptacles by stretch-blowing said parisons in a forming unit for stretch-blowing the parisons, said transferring unit being interposed between said moulding unit and said forming unit, said moulding unit, said forming unit and said transferring unit being arranged in an ultra-clean environment, i.e. in a volume that is separated from the external environment by means of a physical separation that has the purpose of limiting the entrance of contaminants from the external environment, said ultra-clean environment being maintained at an overpressure value of about 10 Pa, microfiltered air flows coming from HEPA filters of level H13 being used to generate such overpressure, the step of sterilizing the moulded parisons occurring at least partly during the step of thermal conditioning of the parisons in a plurality of sterilization devices configured to sterilize at least internally said parisons, said sterilization devices being installed on said transferring unit, one of the sterilization devices being located at each supporting station. - obtaining parisons by melting and moulding granules of thermoplastic material in a moulding unit for moulding parisons, each of said parisons having a tubular body and a neck with an annular protrusion called bague, the parisons leaving the moulding unit with the tubular body at a temperature above 100°C and the neck being cooled so as to have a temperature between 20°C and 40°C, this creating a temperature imbalance between the neck and the tubular body, which temperature imbalance generates an uncontrolled thermal profile which extends down below the bague; - sterilizing the moulded parisons; - submitting the moulded parisons to thermal conditioning in a transferring unit comprising a star-wheel having a plurality of supporting stations for supporting the parisons by their neck, in each supporting station being arranged one thermal conditioning device configured to heat a tubular body of said parisons so that said parisons leaving the transferring unit have a predefined thermal profile adapted to allow forming by stretch-blowing; - obtaining the receptacles by stretch-blowing said parisons in a forming unit for stretch-blowing the parisons, said transferring unit being interposed between said moulding unit and said forming unit,