The aim of the present disclosure was to provide an improved oxidizing agent preparation for oxidative color modifying agents, which are present as soap based gels and contain ammonia as the alkalizing agent and optionally at least one oxidation dye precursor, and have a pH in the range of from 8 to 11.5, measured at 20° C., with which homogeneous and viscosity-stable application mixtures can be produced that release less ammonia during the entire leave-in time. It was surprisingly found that aqueous hydrogen peroxide preparations which contain selected 1-alkanols, glyceryl fatty acid esters, ethoxylated fatty alcohols, polyols and oils, achieve said aim in a very satisfactory manner.