In food processing, it is a mild preservation technology, for both pasteurization and sterilization, where vitamins, natural colorings and flavorings are preserved. The cell wall, cell membrane and membrane surrounding the nucleus of micro-organisms break down and unwanted substances can penetrate.
Isostatic high-pressure presses deactivate microorganisms and enzymes and denature proteins and polysaccharides. They apply uniform, simultaneous, and omnidirectional pressure to food products.
In addition, changes also can be made to macromolecules, such as crystallizing of lipids, denaturation of proteins and enzymes and gelatinization of starch. Pressure treatment can be used to alter the functional and sensory properties of various food components, especially proteins. The tertiary and quaternary structures of molecules which are maintained mainly by hydrophobic and ionic interactions are beneficially altered by high pressure above 200 MPa (25).
The applied pressure is isostatic, so that the pressure is uniformly propagated throughout the entire product. The temperature of the treated foodstuff increases to a maximum of 25°C by the energy input via the high pressure. If this temperature rise is undesirable, cooling of the pressure chamber is possible.
Among the advantages of isostatic pressing:
*Uniform strength in all directions
*Uniform density
*Shape flexibility
Other industries that applied isostatic press include: pharmaceuticals, explosives, chemicals, nuclear fuel Ferrites. There are two main types of isostatic presses; cold isostatic presses (CIP) that function at room temperature and hot isostatic presses (HIP) that function at elevated temperatures.
Isostatic pressing in food
