Cold Chain Humidity Control – or rather lack of it! – Part 1

Professionals and corporate entities working in the wider food industry do not always fully appreciate the important role humidity plays in their cold chains (walk-in cold rooms in particular).

Cold chain temperature control alone does not ensure a long shelf-life of perishable products.

Why?

The very nature of NATURE is that all living beings comprise mostly of water.

Water makes up the following percentages of fresh produce:

• 90% of fruit and vegetables
• 75% of fresh meat
• 75% of fresh fish

Should any of the above produce be stored in a cold chain at a humidity level that is less that their water content (even 5% less), even for a few hours, the commercial value of the produce will deteriorate, as the produce will:

• Wilt/dry out (loss of moisture to drier environment)
• Discolour – especially hanging meat carcasses (loss of texture due to water loss)
• Develop sliminess on surface – especially fresh fish, mushrooms

Finally, and most important message to take away from this editorial, is that humidity control is required at EACH of the following stages:

• post-harvest (at pack house where produce is packed for distribution)
• post slaughter (at abattoir)
• transport (moving stock from farm to market – from market to wholesaler)
• markets (where agents keep their fresh produce pending sale)
• wholesaler (where produce is kept pending sale and then transported to client)
• kitchen (whether at home, hotel, restaurant, canteen, etc)
• point of sale (supermarket, butchery, etc)

Unfortunately, very few if any of the foregoing stages, make it a non-negotiable HACCP protocol that the correct humidity levels be maintained hence qualitative shelf-life is a non-starter from the very beginning.