Cold chain
Also known as: unbroken cold chain, cold chain logistics
Short definitionA perishable product never leaving its own temperature limits at any stage from the producer to the final buyer. For fresh food that limit is usually 0–4 °C, for frozen food −18 °C at most, for medicines 2–8 °C.
The goods of a customer who builds a cold store pass through a chain: first cooling at the field or the abattoir, processing, the store, the refrigerated truck body, the distribution centre, the shop cabinet. Quality lost in one link is not won back in the next, because the hours spent warm add up. When temperature rises by 10 K, spoilage runs two to three times faster. Snow in a frozen pack and pieces stuck together tell you the product warmed up once on the way.
In a project the place that needs most attention is the loading dock. An enclosed dock with shelters, a dispatch hall held at 0/+5 °C, strip curtains and rapid doors are drawn so that pallets do not wait in the sun. Product is cooled in the store; a refrigerated vehicle only has the power to carry cold goods cold. Temperature is logged every few minutes and an alarm sounds when it leaves the limits. These records are what an audit asks for; a store without them cannot show that it stored the product correctly.