FFS & flow wrap
We look at how the film forms and seals on the line, as well as the barrier the food requires.
Terralign / packaging science
Materials, formats and pack performance.
Technical advice on films, pouches, trays, barrier papers and how they perform with the food and packing process.
Bring us a technical questionFormats & structures
Flexible films, formed packs and barrier paper.
We assess a structure against the product, packing line and target market.
Pouches & laminates
Each layer, closure and seal has a job to do. We consider those functions alongside filling conditions and handling.
Thermoform & trays
We examine forming and lidding requirements, including MAP applications and protection during distribution.
Paper with barrier
A paper-based pack still needs the right barrier and seal. We also examine how it converts and which end-of-life claims its construction may support.
See more formats and materials we review
In practice
Formats and materials we review
These are some of the formats, materials and packing processes we can assess. The useful question is how a particular combination works for your food, line and market.
Packs and formats
- Tray-sealed packs, including PP, PET and CPET trays
- Thermoformed packs and cavities
- Vacuum bags, pouches and flow wraps
- Modified-atmosphere (MAP) and vacuum-skin (VSP) packs
Films and webs
- Single-layer and multilayer films
- Forming and non-forming webs
- Lidding and vacuum-skin films
- Pouch laminates, barrier and sealant structures
Packing processes
- Tray sealing and inline thermoforming
- Horizontal and vertical form-fill-seal (FFS)
- Flow wrapping, vacuum packing and gas flushing
- Material fit with existing equipment and tooling
Considering paper or board?
We also review coated and barrier papers, paperboard trays and boards for vacuum-skin packs. Paper grade and grammage (gsm), coating, barrier, stiffness, sealing and runnability all matter when a structure moves onto a packing line. We can help develop and compare options, then identify the trials and market-specific evidence needed before making performance or recyclability claims.
Your format is not listed? Tell us what you are working with and we will confirm whether it fits our scope.
Inside a flexible film
Five layers. Five different jobs.
This illustrative construction shows how separate layers can work together as one flexible film. The materials, order and performance of a real structure depend on the product and packing process.
Outside
Food-contact side
01 / Inner surface Sealant and food-contact layer
The inner layer forms the sealing surface and may contact the packed product. Seal performance depends on the material, equipment, temperature, pressure and dwell time.
02 / Tie First tie layer
This tie layer helps bond the inner sealant to the barrier layer when the selected materials would not otherwise adhere reliably.
03 / Barrier Barrier layer
A barrier layer may be selected to slow oxygen or water-vapour transmission. Performance depends on the complete structure, thickness and stated test conditions.
04 / Tie Second tie layer
This tie layer connects the other side of the barrier to the outer structure, helping the five-layer construction behave as one film.
05 / Outer surface Print-facing outer layer
The outside layer can carry print and contribute stiffness, toughness and handling. Its exact role depends on the chosen material and converting process.
Performance data
What the test conditions mean.
An OTR or WVTR/MVTR figure needs a test method, temperature, humidity and structure before it can be applied to a product. We review those conditions alongside the pack requirements.
Seal strength, puncture resistance, runnability and shelf life also depend on the finished pack and process. A material data sheet alone cannot establish pack performance.
The brief
What we need to review a material.
These details help us identify relevant data and keep the review tied to the application.
What must the pack protect?
Describe the food, intended shelf life, storage and distribution conditions, plus any known failure such as leakage or damage.
What happens on the line?
Share the pack format, forming or filling process, sealing method and practical line constraints.
Where will it be sold?
Name the markets and any proposed food-contact, recyclability or compostability claims. Requirements and recovery systems vary by place.
What information is available?
Specifications, test reports and supplier statements show what can be assessed now and where further testing or specialist input may be needed.
A short outline is enough to begin. Send us your packaging question.
Common questions
Questions we hear about materials.
The answer depends on the product, finished pack and market.
Is an OTR or WVTR figure enough to choose a film?
Not on its own. The conditions behind the number, the complete structure, the product and the finished pack all matter. We first ask what the pack must protect and what data is still missing.
Can barrier paper replace the current structure?
It depends on what the current pack does for the food and how it runs on the line. We would compare protection and sealing performance, then check the intended end-of-life route for the complete new pack.
Is this pack recyclable or compostable in our market?
We would need the complete pack and the named market before researching the applicable rules and systems. Terralign can map the evidence and gaps; it does not certify the claim.
What should we send for a first review?
Start with the food, current or proposed pack, packing process, target markets and the decision deadline. A short, non-confidential outline is enough for an initial scope discussion.
Have a different question? Send it to Terralign.
Market requirements
Check the market before changing the pack.
Food-contact requirements, EPR obligations, packaging taxes and local recovery systems can affect the case for a structure. We include those questions in the technical review.
See packaging rules researchAreas reviewedIllustrative
ProtectFood and shelf-life requirements.
ProduceLine, tooling and sealing constraints.
MarketApplicable rules and support for claims.
CheckTests and further confirmation required.
Technical enquiry
Where is the pack underperforming?
Share the product, current format, target market and the performance or process issue you need to resolve.