Versaperm Vapour Permeability measurement

Measuring the permeability of confectionery packaging


Measuring the vapour or gas permeability of snack packagingMeasuring the permeability of confectionery packaging

Several of these place an increasing burden on the confectionery's packaging to maintain existing (often very low) moisture content levels to reduce oxidation and texture degradation.  

The critical physical factor in these (and indeed in preserving aromas) is the vapour permeability of the packaging.

Packaging needs to be innovative to attract customers – but it must also prevent products from drying-out or over-hydrating. Furthermore, it should increase shelf life.  In virtually all cases of packaged snacks water vapour is the culprit and causes damage and reduced shelf life that is estimated to cost millions in the UK alone.  

Confectionery - vapour permeability and shelf life

Most confectionery is bought on impulse to meet the demands or a sweet-tooth or to satisfy the need for craving, sugar rush or energy boost.  Increasingly they are marketed on a health platform with low fat, low calorie, sugar alternatives, vitamins or other features.  There is also a general trend towards freshness, more real fruit, stronger flavours and increased shelf-life.

vapour permeability

Our equipment can test (for product development or QC) the permeability of a huge range of products and packages – from metalized foil packages, laminated films and sachets through to sugar coatings, edible films and barrier materials. 

It also allows you to measurement of the equilibrium relative humidity (ERH) of snacks that might are be decomposed by other water content measuring techniques.

And, if your need for testing does not demand its own equipment, we also offer a fast and economical testing service for the snack food and confectionery industries. 

It is worth taking a very brief look at some of the widely used packaging materials:-

Co-extruded Oriented Polypropylene (COPP): Is a good moisture barrier, gas barrier properties can be improved by coating it with PVdC. It can be used when gas flow is desired for MAP (Modified Atmosphere Packaging).

Ethylene Vinyl Acetate (EVA): Has high flexibility, and high permeability to water vapour and gases with excellent oil and grease resistance.

Ethylene Vinyl Acetate, has superior sealing qualities and blended polyethylene can make a strong peelable seal.

Vapour Permeability measurement confectionaryEthylene Vinyl Alcohol (EVOH): A moisture sensitive, very high gas-barrier material, again often sandwiched.

High Density Polyethylene: with its higher softening point (than LDPE) it provides  a physical barrier buts not suitable as a thermoformable sealant layer, clarity is poor.

High-impact Polystyrene: Opaque, thermoformable, and a moderately low gas-barrier.

Inomers: Are similar to polyethylene but have a high tack and can seal through a level of surface contamination.

Linear Low-Density Polyethylene (LLDPE): This has greater impact and puncture strength, tear resistance, elongation and resistance to cracking. It is commonly used for MAP.

Low Density Polyethylene: An extremely versatile material with low water vapour permeability but high gas permeability.

PET: High clarity that forms and thermoforms well.

Polypropylene (PP) and Oriented Polypropylene (OPP): Gives a high water vapour and gas barrier and has excellent grease resistance.

Polystyrene: A clear thermoplastic with a high tensile strength. It is brittle and a poor barrier to moisture vapour and gases.

Polyvinylidene Chloride (PVdC): Used for MAP as a gas-barrier coating, often  sandwiched between other materials. It has outstanding barrier properties with low permeability to water vapour and gases.

Using the most appropriate materials can dramatically extend the life of snacks and preserve flavour, texture quality.