A conductivity probe having one electrode with a small surface (the sensing electrode) can be used for the measurement of the instantaneous local concentration during liquid mixing in an electrolytic solution. The presence of solid particles in the mixing field causes fluctuations of the electrolyte concentration signal, contaminating in this way the concentration measurement. The influences of the volume fraction and size of the solid particles on the electrolyte-concentration signal are investigated. The data indicate how to estimate the effect of the presence of particles in the specification of the electrolyte concentration. Furthermore, a method which allows the measurement of the mean electrolyte concentration at high solids volume fractions in electrolytic liquid/solid suspensions is proposed.