Cold Chain

The cold chain is the set of processes, equipment and records that keep a temperature-sensitive product within a controlled range, without interruption, throughout its entire logistics life: production, storage, transportation, distribution and point of sale. It covers products such as vaccines, biologic drugs, chilled or frozen foods, dairy and chemical reagents, where a deviation of just a few degrees can degrade quality or make the product unusable.

Its core logic is that the chain is only as strong as its weakest link: a single uncontrolled leg (a failing cold room, an unrefrigerated truck, a customs delay) is enough to compromise the whole lot. That is why it depends on continuous monitoring with sensors, alarms for temperature excursions and documented evidence of every handoff. Guaranteeing that continuity is part of the end-to-end traceability that Trazzo coordinates across logistics operations.

How it works in practice

A well-managed cold chain combines three layers: conditioning (cold rooms, refrigerated containers, coolers with gel packs or dry ice), monitoring (data loggers and IoT sensors that continuously record temperature, and sometimes humidity) and governance (procedures, owners for each leg and auditable records). The goal is not just to keep things cold but to prove that the product never left its range: temperature is a data point that must be captured and tied to the lot.

Every product has its own range. Vaccines usually require between 2 and 8 degrees Celsius, many frozen foods call for minus 18 degrees Celsius or colder, and some biologics need ultra-low freezing below minus 60 degrees Celsius. A temperature excursion is any moment when the temperature leaves the allowed range; depending on its duration and magnitude, it may affect nothing or invalidate the entire lot.

Why it matters to the business

The cost of a cold chain break is not just the lost goods. It means recalls, urgent replacement, health risk, regulatory penalties and reputational damage. For pharmaceuticals, regulations require companies to demonstrate control (good distribution practices), and for food, a failure can lead to food poisoning. In international trade of perishables, a deviation detected on arrival can mean an entire container is rejected at destination.

A concrete example in Argentina

A blueberry exporter in northwestern Argentina ships reefer containers to Europe. The fruit must travel at close to 0 degrees Celsius for weeks. If the container suffers a temperature excursion lasting several hours during a port delay in Buenos Aires or a transshipment, the fruit can arrive with a shorter shelf life or simply rotten. With data loggers and real-time monitoring, the exporter detects the event, decides whether to reroute the cargo and has documented evidence to dispute the claim with the shipping line or the insurer, instead of losing it for lack of proof.

Common mistakes

• Relying only on checks at the start and end, without continuous monitoring of the middle legs, which is where most failures happen.
• Not clearly defining which excursion invalidates the lot, which leads to discarding good product or, worse, releasing compromised product.
• Treating temperature as an isolated data point instead of linking it to the lot and expiration date, losing the ability to run a selective recall.
• Not recording handoffs of responsibility between carrier, warehouse and distributor, leaving gaps in the chain with no owner.

Cold chain vs traceability: how they differ

The two concepts complement each other, but they are not the same. The cold chain is about maintaining and proving a condition (temperature) along the route; traceability is about reconstructing the full route of a product, whether or not it depends on temperature. A mature operation uses traceability as the thread that ties every temperature reading to a specific lot and stage.

In practice, monitoring temperature without traceability leaves data with no context, and tracing without temperature control leaves a route with no quality guarantee. Logistics operations need both integrated to respond with evidence to a customer, an auditor or an insurer.