The purpose of the present study was to determine the influence of protein isolation from potato juice and acetylation on the chemical composition and chosen functional properties of obtained preparations. Potato protein preparations used for the experiment were obtained by thermal coagulation and membrane technology. Preparations containing thermal coagulated (PPI) and native (PPC) protein, respectively, were subjected to the chemical modification by acetylation with the use of different doses of acetic anhydride. Changes in chemical composition (total and coagulable protein content, ash content and amino acid composition), functional properties (water holding capacity, oil holding capacity, protein solubility index, emulsification properties...