Freezer-burn is a major cause of wastage in food processing plants.

When water vapour escapes from the product's frozen surface and migrates through the packaging, it causes an unappetising brown stain or appears as a fuzzy greyish-white spot on the food, which then has to be discarded for quality reasons. Most plastics are impermeable to water as a liquid, but all allow water vapour to pass through to varying degrees.

Conventional measurements of vapour permeability take days, or even weeks, but Versaperm has claimed its new instrument, the WVTR MK VI, can measure the water vapour permeability of packaging materials, then produce the reading in just 30 minutes.