High Pressure Processing (HPP) is a cold pasteurization technique by which products, already sealed in its final package, are introduced into a vessel and subjected to a high level of isostatic pressure (300–600MPa/43,500-87,000psi) transmitted by water.
Please watch- http://www.youtube.com/watch?v=r5Ufqp_Fq6o
I have 2 questions and somehow i am not able to understand below mentioned.
1) how is it possible to pressurize a plastic container bottle(As in the video) without collapsing the container?
2) what happens if we use a plastic polyethylene bag of juice instead of bottle?Will that bag also sustains such a huge pressure?
Best Answer
It works because the plastic bottles are filled with water and water is almost incompressible. When subjected to high pressure, the volume inside the bottle stays almost the same (there is a small air bubble that will be compressed), thus the bottle is not crushed.
I believe that a plastic bag would work just as well. The hydrostatic pressure is uniform so there would be no force to deform and tear the bag. And the polyethylene itself should withstand the pressure - after all, it is produced at pressures up to 3000 atm.