Impact of high pressure homogenization on the properties of potato flour film-forming dispersions and the resulting films

The properties of potato flour film-forming dispersions obtained with high pressure homogenization (HPH) at a pressure ranging from 15 to 60 MPa with 1, 3, and 5 passes and their resultant films were investigated. The median particle size of the dispersions with HPH treatment decreased from 111.65 μm to 10.71 μm, and the result was confirmed by microscopic images. Although the apparent viscosity of homogenized dispersion was smaller than that of the unhomogenized sample, it was noted that the apparent viscosity of homogenized dispersions increased sequentially with pressure and pass. The resultant films with HPH treatment had smoother surfaces, better moisture barrier properties, higher hydrophobicity, lower moisture content, and better transparency. The HPH treatment favored the retrogradation of film, but glass transition temperature had no significant change. The use of HPH increased tensile strength from 6.58 MPa to 11.14 MPa, while elongation at break decreased first and then increased. Potato flour films with HPH treatment show good physicochemical properties and have potential application in food packaging.