The Package: In order to achieve the best pressure transmission within the food product, the ideal
food for HPP processing has no gas inclusions, no head space in the package, and high moisture
content. Additionally, the type of material used to package the food product also has to be suitable.
The packaging material has to be flexible enough to transmit the pressure without structural damage.
Due to pressurization, the food is compressed and the package has to allow this reversible
deformation. Rigid materials like metal and glass are not recommended, as they will not be able to
withstand the HPP treatment. Vacuum packed products in flexible packages appear ideal for HPP,
particularly if the package can be compressed by about 15 percent without suffering structural
damage and it is able to return to its original shape upon pressure release. Currently, flexible packs,
jars, trays and bottles are used as HPP packaging.