From Top Wiki

Jump to: navigation, search

PATS, also known as Pressure Assisted Thermal Sterilisation or HPP-sterilisation (High Pressure Processing Sterilisation) is a preservation technique for food. It uses a combined effect of high temperature and high pressure.



Figuur 1 Proces flow van PATS/HPP sterilisatie

Figure 1 Process flow in PATS/HPP sterilisation

In preserving by high pressure, the product is heated by adiabatic heating (3-5 °C per 100 MPa). In PATS or HPP-sterilisation, this adiabatic heating effect is used maximally to heat preheated products to sterilisation temperature. This heating process is fast and uniform.

Process steps

The product is filled into the packaging and sealed to close (Figure 1). Then the product is preheated to 70-80 °C in a continuous heater (in-line) or by using volumetric heating (eg microwave or RF). Volumetric heating goes faster than heating from outside, resulting in better product quality. After preheating, the product is placed into a warmed pressure vessel. In the vessel, pressures of 600 – 800 MPa can be reached. The product is kept under this pressure for about 3 minutes. The temperature increases to 95-115 °C due to the adiabatic heating. Part of the adiabatic heat is lost to the pressure vessel, which is cooler than the product (~70 °C vessel, product 95-115 °C). Due to this temperature difference, it cannot be guaranteed that the sterilisation process reaches the desired parameters. As soon as the pressure is released from the vessel, the temperature decreases to start temperature. After the high pressure treatment, the product is cooled.


PATS or HPP-sterilisation is a batch process, in which the packaged product is treated. The added value lies mostly in products as ready-to-eat meals, thick sauces and soups (with particles). Product quality

Figuur 2 Effect van conserveringsmethodes op de aromacomponenten in verse basilicum

Figure 2 Effect of preservation methods on aroma components in fresh basil

Preservation of a product by PATS/HPP sterilisation influences the presence of micro-organisms, enzymes, flavour, texture and the vitamin content.

Advantages and disadvantages



Equipment availability

There are no PATS systems on a commercial scale available yet. The following equipment suppliers are working on the development:

Investment and running costs

There is no commercial equipment on the market yet. This makes it difficult to estimate the investment and running costs. The total investment for a HPP-unit and preheating are estimated at €1.400.000,-. The total running consts are estimated at €0.15/kg.


External links

Personal tools