Method for producing nucleation of solid phase from a supercooled liquid

A method of manufacturing a frozen or partially-frozen product which method includes:

• a) providing a liquid material in a substantially sealed vessel;
• b) subjecting the liquid material to a negative pressure;
• and
• c) subjecting the liquid material, whilst under the negative pressure, to a temperature substantially less than 0° C.;
• wherein the negative pressure is achieved by heating the vessel thereby permitting the liquid to expand until it substantially fills the vessel, prior to step c), such that, when the vessel is cooled in step c), adhesion of the liquid to at least one internal surface of the vessel, thereby substantially preventing the liquid from contracting at a greater rate than the vessel's internal volume and progressively increasing negative pressure develops.