An internal mix atomizing spray nozzle assembly for preparing a spray-dried lipid and protein component-containing composition includes a fluid nozzle with a liquid flow passage having a liquid discharge opening directed into a mixing chamber, a spray tip comprising the mixing chamber and having at least one discharge orifice at a free end, an air supply system comprising an annular air flow passage arranged at least essentially coaxial to the liquid flow passage and having an annular air discharge opening directed into the mixing chamber. The annular air flow passage may be cylindrical with a constant cross section.
