A non-chemical apparatus and method to lower the surface tension of a solution of liquid water and gaseous oxygen. An apparatus of the present invention comprises a source of chilled purified water, and gaseous oxygen fed into a positive displacement pump, followed by a cylinder reduced at one end by means of a convergent cone, a section of a smaller diameter cylinder attached to a divergent cone tapering up to another cylinder of a diameter the same or larger than the original cylinder. A coil of refrigeration tubing is wrapped around the smaller center cylinder to control the temperature of the inner cylinder surface.
