Effects of high-pressure homogenization on physical and thermal properties of citrus fiber

Abstract

In this study, the adsorption and morphology properties of the dehydrated citrus fiber dispersion produced by high-pressure homogenization (90 MPa and 160 MPa) were investigated, and the microstructure and thermal properties were further analyzed for their alteration of physical properties. The fiber dispersions were homogenized at two pressure levels (90 MPa and 160 MPa). The average particle size of citrus fiber reduced significantly after the high-pressure homogenization (HPH) process. Meanwhile, the HPH process significantly increased the adsorption properties both for water and oil. Citrus fiber particles changed from spherical to multi-branched flake-like structure after HPH. On the molecular level, it is shown that the main components of citrus fiber were transformed and the crystal structure was changed after the HPH. In addition, the glass transition temperature (Tg) of the citrus fiber reduced with the increase of HPH pressure, with the lowest Tg of samples dropped from 71.14 ± 1.21 to 51.08 ± 1.33 °C after HPH.