Cold Chain Humidity Control – or rather lack of it! Part 2

Whilst the appropriate cold chain ambient temperature is imperative for the safe storage of edible perishables, humidity control is equally important to maintain weight and qualitative condition of the produce.

By way of example, the cold chain storage practices below will be in full compliance with most Cold Chain HACCP Protocols:

  • fresh fruit and vegetables stored at 5ºC and 68% relative humidity (RH) in a chef’s walk-in cold room (or even under the counter fridge)
  • a consignment of hanging meat stored at 2ºC and 68% RH in a butchery walk-in cold room

Both examples above will pass a food safety audit with ‘flying colours’.

But in BOTH instances (even in the space of a few hours):

  • the fruit & veg will begin to forgo qualitative condition, lose weight, and wilt
  • the meat will lose weight and begin to discolour


In both examples the %RH is far TOO low:

  • Fresh produce should ideally be stored at 90%RH because that matches the water content of the latter
  • Hanging meat should be stored at 82%RH because that slightly exceeds the 75% water content of the latter

Refrigeration systems (even brand-new ones) tend to dry out the internal air of cold rooms during off-peak work shifts.

Polar Africa offers both mechanical and natural mineral humidity control interventions to maintain RH%.