Barrier is not one property. A structure can be excellent against moisture and poor against oxygen. Which barrier matters depends on what is inside and how long it needs to hold: an oxygen-sensitive food puree and a hygroscopic powder need different answers.
Where you meet this term
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Learn
What packaging is used for viscous products?
Pastes, purees and heavy liquids are decided by how you get them out, not how you get them in.
LearnHow do powders move inside a manufacturing plant?
The packaging usually follows the handling method, the dust behaviour and the batch size.
TermLiner
A bag or insert placed inside a container so the container never touches the product.
TermPrimary packaging
The layer in contact with the product.
If this becomes a real requirement
CAQUIN sources industrial packaging to specification. Send what you use today, roughly how much, and where it ships — a photo is enough to start.