Cold Chain Logistics Management: How to Handle Temperature-Sensitive Goods

When ice cream melts in your hands on a hot day, it can be a bit frustrating; but if a load of vaccines can’t be used because it went bad due to improper storage or transportation conditions, the results are a lot more serious, if not fatal.

There are a number of food products, medications, and other goods that have to be maintained at a certain temperature. So, it’s important that all supply chain parties (3PLs, carriers, storage facilities, etc.) dealing with such goods understand how to handle them correctly. In this post, we’ll talk about what cold chain logistics is, how to manage it at different stages, and which technologies support these activities.

What is cold chain logistics?

A cold chain is a supply chain that deals with perishable, temperature-sensitive goods (also called cool cargo) such as fresh produce, meat, dairy, seafood, chemicals, pharmaceuticals, flowers, wine, etc.

Usually, a specific low-temperature range has to be maintained to ensure the quality and integrity of perishable goods, i.e., some groups of products have to be refrigerated, some must be frozen, while yet others require extreme conditions (a so-called ultralow chain or deep freeze). Failure to maintain the right temperature leads to product spoilage and, ultimately, financial losses.

Cold chain logistics is a set of activities aimed at handling and transporting such items securely from the manufacturer or supplier to consumer.

A common cold chain scenario

Obviously, the longer the journey between the original supplier and end consumer and the more legs (and/or transportation modes) involved, the more difficult it is to maintain the necessary temperature. For example, in the case of international shipping, freight sometimes goes through multiple storage facilities or distribution centers and has to be reloaded several times. Unless items are permanently kept in a sealed refrigerated container, all these activities increase the risks of temperature fluctuations.

Within the cold chain logistics process, the packaging, storage, and shipping stages cause the greatest complications.

Cold chain packaging

Ensuring optimal temperature starts with selecting the proper type of packaging, container, and refrigerating method. All that, in turn, depends on multiple factors, such as

type of cargo,
required temperature and humidity levels,
size of shipment,
duration of transit,
outside temperature (it’s especially important in case of climate changes for long-distance shipments), and so on.

For every type of temperature-sensitive shipment, different packaging is used. For example, vaccines are transported in small insulated boxes, while 53 foot reefers with inbuilt refrigerating units are used to haul foodstuff. We’ll talk more about packaging technologies in one of the next sections.

Cold chain storage

Warehousing is a complex system that involves numerous processes from storage itself to consolidation/deconsolidation to loading/unloading. Within cold chains, specialized warehouse facilities also often offer such focused services as blast freezing, precooling, frozen receiving, ripening, inspection checks, and so on.

At this stage, it’s important to design appropriate facilities with optimal climate control (both for storage and loading areas) as well as implement certain practices when handling perishable goods.

Cold chain shipping and tracking

As we mentioned above, transporting cool cargo requires specialized equipment known as reefers or freezers. Those are special refrigerated trucks, railcars, cargo ships, and aircraft. Often, not only temperature but also humidity must be controlled, so such equipment has to be capable of that as well.

There’s one more process that’s hard to put in a stage sequence but that’s still crucial in any supply chain. Tracking shipments while en route is always important, but in the case of cold chain, monitoring cargo environmental conditions is essential to ensure efficiency. Shippers, carriers, and consignees alike want to have access to monitoring data for quality assurance and performance assessment.

Cold chain logistics use cases

Multiple industries, including agriculture, manufacturing, and healthcare, strongly rely on cold chain logistics to safely store and transport perishables. Today, the need for such services keeps increasing due to changing consumer demand, trends like “from farm to fork,” and the necessity for new drugs and vaccines. Let’s look closer at industry sectors that need cold chains the most.

Cold chain in food industry

Storing and transporting perishable food products is the oldest and most obvious cold chain use case, originating centuries ago to avoid rot or mold. We all know from our middle school (and our own experience) that the quality of certain food categories degrades with time because of natural chemical reactions – reactions that can be slowed down with lower temperatures.

There are several categories of food that require different thermal conditions.

Banana. Tropical fruits like bananas or pineapples undergo controlled ripening as they are transported, so they need a stable range of 12° to 14°C (53° to 57°F).

Chill. Most vegetables, fruits, dairy products, and meat must be refrigerated around 2° to 4°C (35° to 39°F).

Frozen. Meats, bread, cakes, and most other products that need freezing require temperatures between -10° and -20°C (14° to -4°F).

Deep-frozen. Seafood, ice cream, and some other items have to be deep-frozen or stay between -25° to -30°C (-13° to -22°F).

Cold chain in pharmaceutics

The demand for cold chain logistics services in pharma has grown steadily over the last few years. The 2020 Biopharma Cold Chain Sourcebook predicts that this market will be worth $21.3 billion by 2024 (up from 2019’s $15.7 billion). Blood, stem cells, tissues, transplant organs, as well as diverse drugs and vaccines – all these items need a range of 2° to 8°C and sometimes down to -80°C. If the required temperature level is not maintained, such products can become useless or even harmful for patients.

Recently, billions of COVID-19 vaccines had to be spread out on a global scale – and they require a stable, ultra-low temperature of below -70°C (so do some others, including the Ebola vaccine). Besides, a large number of new drugs being approved by the US Food and Drug Administration is temperature-sensitive as well. So, the need to develop proper cold chain infrastructure to maintain required conditions at all stages is higher than ever.

Typically, if pharma goods have to be shipped urgently, they are transported by air. However, if time is not critical, ocean transportation is preferred because it’s cheaper and safer (i.e., less subject to temperature breaches).

Also, in contrast with the food industry, there is a higher demand for packaging options and containers that can maintain ultra-low temperatures. So, let’s finally discuss which special materials and equipment are commonly used in cold chains to protect the integrity of shipments.

Cold chain equipment and packaging options

We’ve already indicated that usually reefer trailers, diverse containers, and even specialized vessels are used to transport temperature-sensitive products. Liquefied gasses (such as oxygen, nitrogen, argon, CO2, etc.) are stored and transported in special cryogenic tanks, trailers, and railcars.

Meanwhile, for storage purposes, warehouse/terminal facilities and distribution centers are equipped with capacious walk-in coolers and refrigerators that maintain a stable temperature. To store pharmaceuticals, drugs, tissue samples, and other medical items, there’s a wide variety of laboratory refrigerators and freezers capable of supporting the required temperature.

As for packaging, there’s a huge range of cooling products to keep perishables cold. There are two main categories of such technologies.

Passive cold containers rely on dry ice, gel packs, gel bottles, liquid nitrogen, eutectic plates, quilts, and other cooling/auxiliary stuff to keep the internal temperature low. Pharma products can be more demanding and require ultra-low freezing, so specialized containers are being developed to satisfy industry needs.