Apparatus for inspecting transparent cylindrical containers containing milky products, in particular for medical applications, comprising: - a support and/or gripping device for a cylindrical container, suitable to support it and provided with means for making it rotate about a vertical rotation axis (Y-Y), coincident with an axis of cylindrical axial-symmetry (X-X) of said cylindrical container, - a video camera directed so as to frame and capture images, in the form of pixels, of a window of a side wall of the cylindrical container, - a first collimated lighting device, directed so as to illuminate said window, - a second lighting device, collimated and oriented so as to illuminate said window, placed opposite the first lighting device, in a symmetrical position with respect to the window, - a control unit operatively connected to the support and/or gripping device, the video camera and to said first and second lighting devices (24,28), and programmed to: - capture first and second partial images (36',36") of said window at constant angular intervals, alternatively activating the first and second lighting devices (24,28), for each angular interval, until a complete rotation of 360° of the cylindrical container is performed, - associate, without interruption, the first and second partial images (36',36") obtained by alternatively activating the first lighting device, so as to obtain a first aggregate image of the cylindrical container, and of the second lighting device, so as to obtain a second aggregate image (40") of the cylindrical container, - identify, within each aggregate image (40',40"), the presence of possible irregular pixels having chromatic differences corresponding to contaminants, - realize, in case of identification of at least one of said irregular pixels, a control image derived from the difference between said first and second aggregate images (40',40") and catalogue, according to the detection of a projected shadow of the contaminant in said control image, the internal or external position of the contaminant with respect to the side wall of the cylindrical container. - a support and/or gripping device for a cylindrical container, suitable to support it and provided with means for making it rotate about a vertical rotation axis (Y-Y), coincident with an axis of cylindrical axial-symmetry (X-X) of said cylindrical container, - a video camera directed so as to frame and capture images, in the form of pixels, of a window of a side wall of the cylindrical container, - a first collimated lighting device, directed so as to illuminate said window, - a second lighting device, collimated and oriented so as to illuminate said window, placed opposite the first lighting device, in a symmetrical position with respect to the window, - a control unit operatively connected to the support and/or gripping device, the video camera and to said first and second lighting devices (24,28), and programmed to: - capture first and second partial images (36',36") of said window at constant angular intervals, alternatively activating the first and second lighting devices (24,28), for each angular interval, until a complete rotation of 360° of the cylindrical container is performed, - associate, without interruption, the first and second partial images (36',36") obtained by alternatively activating the first lighting device, so as to obtain a first aggregate image of the cylindrical container, and of the second lighting device, so as to obtain a second aggregate image (40") of the cylindrical container, - identify, within each aggregate image (40',40"), the presence of possible irregular pixels having chromatic differences corresponding to contaminants, - realize, in case of identification of at least one of said irregular pixels, a control image derived from the difference between said first and second aggregate images (40',40") and catalogue, according to the detection of a projected shadow of the contaminant in said control image, the internal or external position of the contaminant with respect to the side wall of the cylindrical container.