A procedure for fitting small angle X-ray scattering curves in order to describe the structure of Al-organic precipitates was elaborated in the log and range from -0.2 to -0.8. Models were built by considering the Al species (monomers, dimers, trimers, and tridecamers) as hard spheres associated in short linear chains. Size of the spheres and chain length were defined from results obtained through other methods, mainly Al-27 NMR. The procedure was tested by performing the fit on lactate/Al scattering curves.