The present invention relates to a re-closable package, wherein at least one layer of said package is derived and fabricated essentially from a single piece of packaging material, has at least an inner and outer chamber, each capable of holding one or more separate or mixed solid or liquid food components. It also relates to one or more mechanisms within said package design and configuration preferentially allowing controlled movement of gas but not liquid and/or solids both within the package and/or from within the package to the outside. It further relates to a method for controlling and selectively modifying a number of processing conditions within said packaging, particularly pack pressure, gas volume and gas composition. It also relates to package design capability to accelerate and/or optimize product processing within any food sterilization or pasteurization system and its subsequent handling, storage and transportation without further modification.