It depends on how sensitive your product is to air, moisture, light or odours. Ask yourself: does it lose taste or aroma quickly, choose a high oxygen barrier, such as EVOH or aluminium. Does it get soft or clump due to moisture, choose a moisture barrier film. Is it sensitive to light, consider an opaque or metallized layer. Do you want it to remain recyclable, a mono PE or mono PP with a light barrier coating is often the best choice. Not sure? Contact one of our specialists, we are happy to help.