A refrigerated trailer can arrive on time, show the correct set point and still deliver food with less shelf life than expected.
That is because protecting food quality requires more than keeping a vehicle cold. Product temperature before loading, warehouse dwell time, airflow, door openings, humidity and the speed of response to an alert can all affect a shipment.
The scale of the issue is significant. The Food and Agriculture Organization estimates that 13.3% of global food production (around 1.31 billion tonnes) is lost between harvest and retail. Fruit and vegetables have the highest loss rate, at 25.4%. (FAO)
A separate UNEP–FAO assessment found that inadequate refrigeration contributed to the loss of approximately 526 million tonnes of food, enough to feed an estimated one billion people. (UNEP)
Temperature-controlled transport is therefore not only a logistics service. It supports food safety, shelf life, sustainability and commercial performance.
Temperature-controlled transport is the movement of food within a defined and monitored temperature range.
It includes refrigerated, frozen and controlled-ambient transport, but the complete cold chain extends beyond the vehicle. It also covers:
The objective is to maintain the conditions required by the specific product throughout its complete journey.
EU food-hygiene rules state that the cold chain should not be interrupted for products that could support pathogenic microorganisms or toxin formation. Vehicles and containers must also be able to maintain (and, where necessary, monitor) suitable temperatures.
One of the most common cold-chain misconceptions is that every food product should be transported at the lowest possible temperature.
That can damage certain products.
For example, quick-frozen food in the EU must generally be maintained at –18°C or colder, with only brief upward fluctuations of up to 3°C permitted during transport. Fresh fish must be kept close to the temperature of melting ice.
Bananas are different. Mature-green Cavendish bananas are typically transported at approximately 13–14°C. Exposure below 13°C can cause chilling injury, leading to discolouration, poor ripening and greater sensitivity to physical damage.
The correct temperature is therefore not simply “cold.” It is the validated range for that product, packaging, maturity, journey and intended shelf life.
Transport refrigeration is mainly designed to maintain product temperature, not rapidly cool warm pallets.
Before loading, teams should confirm both product and trailer temperature, check that the refrigeration unit is working and pre-cool the vehicle where required.
Air temperature changes quickly. Product temperature changes more slowly.
A sensor near the refrigeration outlet may show acceptable conditions while products near the doors experience a different environment.
One study of chilled cod found temperature differences of up to 10.5°C between pallet positions. Thermal abuse reduced shelf life by approximately 1.5 to three days. (International Journal of Refrigeration)
Monitoring should reflect the actual risk, using air, product or pallet-level data where appropriate.
Many cold-chain failures happen while the vehicle is stationary.
Products can be exposed during picking, staging, loading, inspections, cross-docking and unloading. A short period on a warm dock with open doors may be more damaging than a longer delay inside a closed reefer.
Measure time outside controlled storage, not only journey duration.
Cold air must circulate around the load.
Poor pallet configuration can block floor channels, air-return paths or the space beneath the ceiling. This can create warm zones even when the refrigeration unit appears to operate normally.
Teams should verify pallet height, floor clearance and air-return space before departure.
Mixed loads may improve trailer utilisation but create quality risks.
Products can require different temperatures, humidity, ventilation, hygiene or odour controls. A set point suitable for dairy may be unsuitable for certain fruit.
Before combining products, confirm temperature, hygiene, humidity and delivery-sequence compatibility.
An alert does not protect food. A response does.
Every temperature warning should have:
A useful KPI is alert-to-owner time: the minutes between the first warning and assignment to someone responsible for resolving it.
Two shipments can arrive at the same temperature but have different remaining shelf lives.
One may have remained stable. The other may have experienced repeated periods of elevated temperature before returning to specification.
Research has shown that refrigeration failures can reduce modelled shelf life significantly, including by up to 40% for smoked salmon and 57% for cooked chicken breast in one study. (Food Control)
The key question is therefore not only:
Was the shipment compliant at delivery?
It is also:
How much usable shelf life remains?
Temperature-controlled transport cannot compensate for poor warehouse processes.
A vehicle may collect a load from a cold store, but exposure can still occur during order preparation, staging or loading.
Warehouse and transport teams should align on:
The transition from warehouse to vehicle should be treated as a controlled process with named responsibilities on both sides.
During transport:
At delivery:
The next stage of food logistics visibility is not simply knowing where a shipment is.
It is understanding:
Warehouse data, shipment milestones, temperature readings, door events and ETA information should not sit in separate systems. When they are connected, teams can detect risks earlier, respond faster and protect more of the product’s commercial and usable life.
Temperature-controlled transport works best when visibility leads to action.
Because in food logistics, the cost of a cold-chain failure is not measured only in degrees.
It is measured in lost shelf life, rejected loads, wasted food and lost customer trust.