Self-cooling food and beverage containers and processes for manufacturing such containers with cryogenic high-pressure refrigerant cooling apparatus are disclosed. A self-cooling beverage container apparatus containing a beverage or other food product, a method of storing cryogenic gases which then cool said food products, and to methods of assembling and operating the apparatus. A self-cooling beverage container includes a container body having an openable portion, a pressure vessel substantially housed within said container body, the pressure vessel having a first chamber for containing a refrigerant, an actuation valve configurable from a closed configuration wherein the refrigerant is maintained within the pressure vessel to an open configuration wherein said refrigerant is allowed to expand and exit the pressure vessel upon opening of said container whereby refrigerant expansion and flow through said outlet conduit cools the contents of said container.