As we move into a world where we see more flexible food packaging replacing traditional glass and metal options, we need to become more aware of how the structure of the packaging will impact the shelf life of food.
Some of the terms:
OTR and WVTR
Oxygen transition rate (OTR) is the rate in which oxygen permeates through a film, the lower the OTR, the higher the barrier. WVTR or Water vapor transition rate is how quickly water vapor will transfer through a film.
Why is the above important?
OTR is the way in which we restrict aerobic microbiological activity food whereas WVTR controls the moisture retention in a packaged product.
As the name suggests a laminated film is constructed by layering the different plastic polymers which come together to provide the features of film such as the barrier, flexibility, clarity, strength, and seal-ability whereas co-extruded film is where the differing plastic polymers are melted and blown together into the finished film thickness. The composition of the film will affect the barrier properties, flexibility and clarity of a film, for example, a film which has a layer of aluminum or nylon will improve the barrier proprieties of a film.
The right option for you?
This will depend on your application, what type of seal, shelf life, visual impact, strength and structure of the packaging you require.
Common polymers used in flexible packaging:
PE – Polyethylene
PA – Polyamide
EVOH – Ethylene-vinyl
EAA – Ethylene and Acrylic Acid
EVA- Ethylene-vinyl Acetate
Vacpack can assist you with all your flexible packing requirements from hot fill, cold fill, freezer grade, retort, and high barrier. We also offer filling and sealing options for most applications
Article credit of Regethermic