The rheologic properties of dark chocolate masses, such as viscosity and the yield stress, decide on whether these masses can be utilised to the purpose of making chocolate and chocolate – coated products. Dark chocolate masses with fat content of 27% to 40% were obtained. These masses were divided into three parts, out of which the first one did not contain any additive of the PGPR emulsifier, the second one contained 0,1% of the PGPR emulsifier and the third one contained 0,2% of the PGPR emulsifier. The PGPR emulsifier brings about a reduction of viscosity and the yield stress. A 2%-concentration of the PGPR emulsifier allows to obtain values of viscosity and the yield stress permitting to reduce the cocoa butter content in the obtained masses by about 4%.