Method for dehydrating liquid, semi-liquid or paste-like products, including a pressure cryogenic step and a lyophilization step

A method for preparing a dehydrated product, comprising:

• a) providing a product in the form of a liquid, semi-liquid or paste-like matrix;
• b) dissolving a gas in the matrix by passing the matrix through an area dense in gas molecules, such a density being obtained (i) either by the gas flow generated by the evaporation of a cryogenic fluid, (ii) or by an increase in pressure, (iii) or by a combination of these two processes;
• c) cryogenizing the gas-rich matrix obtained by the dissolving of the gas in the matrix at a pressure allowing the dissolved gas to be maintained to obtain frozen, non-porous granules, particles or beads;
• d) lyophilizing the granules, particles or beads with a release of the dissolved gas which allows formation of small, very porous particles;
• and
• e) obtaining the dehydrated product in powder form.