Pressure Gelatinization of Potato Starch

This article reviews the pressure gelatinization of starch with a special focus on potato starch which is a key food ingredient and an industrial raw material. First of all, the application of high hydrostatic pressure (HHP), as a novel processing parameter, to food processing is briefly overviewed with some historical backgrounds. It has been revealed in the last century that a starch-water mixture can be gelatinized only with HHP: without heating. In the HHP treatment of a starch system, attention should be paid to the ways of compression and difference in the properties between HHPand heat-gelatinized starches. Physico-chemical changes of various starches after HHP treatment have been studied intensively. However, the behavior of pressure gelatinization has not been studied systematically, since most of the experiments have been carried out at fixed water (or starch) content with only a few treatment pressures. In addition, since potato starch is one of the most pressure-resistant starches, which impose experimental limitations for achievable maximum pressure, pressure gelatinization of potato starch has not been studied sufficiently. Recently, we have treated potato starch-water mixtures of various water (or starch) contents with treatment pressures from 400 to 1,200 MPa, and presented a state diagram of the HHP-treated samples. We expect that the behavior of pressure gelatinization and HHP-induced retrogradation will be understood in more detail with this approach utilizing the state diagram. _____________________________________________________________________________________________________________