3 good practices in the transport of chilled goods

Implementing an efficient and cost-effective cold logistics system is a project that requires careful preparation and consideration of some specific issues. Distributing foodstuffs is of course not something to be taken lightly and it is subject to specific regulations on the transport of temperature-sensitive goods and hygiene standards. To save you time and give you some initial keys to success, below we look at three of the basic factors that will enable you optimise your transport of chilled goods.

Here are some of the questions you will need to answer to be able choose the best form of cold logistics for your needs :

How big is your infrastructure? What are your development objectives? What goods do you want to move? By what means of locomotion?

Pre-cooling the delivery containers

This is something we systematically advise all our customers to do.  Some of them are fortunate enough to be able to store their insulated containers in a temperature-controlled chamber (+4°C or -20°C). This will mean that the air circulating inside the container is already at the right temperature.

Lowering the temperature in advance in this way allows you to :

• Limit the heat exchanges;
• Avoid wasting energy on your cold source;
• Extend the use time of your cold source;

A container that is not at the right temperature is a parameter that must be taken into consideration and which will have an impact on the amount of cooling needed for the intended transport time.

The right sort of cold for the right length of time

A common question asked by our customers is how many eutectic plates are necessary to keep their products cool. We reply by asking a simple question: how long do you need to keep them at the right temperature?

To ensure you have a cost-effective approach to your cold logistics, it is important to always begin with the parameters of your distribution circuit and not your original issue, namely how to keep your goods at a specific temperature. To be able to provide you with the best possible support in this approach, we need to be aware of all the thermal “breaking points” when the cold chain is at risk of being broken. The transit stage very often accounts for 90% of these cases. Only during this phase, you need to be equipped to keep foodstuffs in a secure thermal environment.

There are three important steps in this transit phase: loading/waiting on the dock – transport – unloading/waiting on the dock.

The times each of these three steps last must therefore be included in the estimation of the transit time during which the temperature must be maintained.  You will therefore need to model these waiting times.

---

Case study. A food retailer customer consults us about how to keep its frozen goods at the right temperature (-20°C) during their transit phase. It has the possibility of pre-cooling its containers before loading.

Loading/waiting on the dock = 2 hrs

Transport = 1 hr 30

Unloading/waiting on the dock = 2 hrs

Total time = 5 hr 30

---

To calculate the amount of cooling required, there are two other indispensable indicators that must be added into the mix:  the outside temperature and the volumes to be transported.

Outside temperature

When we conduct thermal studies for customers, we extend the scope of our investigation the ascertaining the thermal environment of each “time zone”. This is because the temperature may be different during the time the goods spend waiting on the dock and that in the lorry they are transported in. This variation in the temperature will have an impact on the amount of cooling needed to compensate for this difference.

---

Case study. A food retailer customer consults us about how to keep its frozen goods at the right temperature (-20°C) during their transit phase.

Loading/waiting on the dock = 2 hrs at +4°C

Transport = 1 hr 30 at +15°C

Unloading/waiting on the dock at the shop = 2 hrs at +15°C

Total time = 5 hr 30

---

Volume to be transported

The volume of foodstuffs to be transported is also an important parameter in the calculation of the amount of cooling. It is a fact that transporting the goods in a fully loaded or in a partially loaded lorry will not have the same impact on the thermal compensation needed. The inertia from the goods themselves is therefore a factor that has to be taken into account.

Checking temperatures of incoming goods

The distribution of chilled and frozen foodstuffs is subject to strict regulations that require the application of rigorous protocols.

In order to avoid food safety scandals, limit wastage, limit nonconformities and guarantee your customers traceability for their goods, we strongly recommend that you undertake systematic temperature checks on your deliveries. You can read our article on this subject to discover our three tips on effective temperature control.

A closer look at Regulation (EC) No. 853/2004

This Regulation requires the organisation of self-monitoring at critical points:

• “Checking on delivery and recording in writing of the compliance and temperature of the goods;
• Checking the temperature of the goods with a calibrated probe-type thermometer, following the written instructions;
• Written recording of the readings taken in above- and below-zero cold storage containers which implies planning the maintenance of the refrigeration equipment;
• Scrapping of products whose use-by date has passed and ensuring their destruction;
• Provision of the means necessary to correct anomalies;
• Compliance with the temperature specified on the labelling for refrigerated products purchased and/or sold pre-packaged.”

Always remember that there is no tolerance on the exceeding of statutory temperatures when presenting the product to the final consumer.

For information, a temperature measured in contact with the packaging that shows a difference of +/-2°C from the statutory temperature is the maximum tolerated. Above this threshold, the measurement of the core temperature of the product is mandatory and it must not exceed +/- 1°C compared to the statutory temperature for the product.

Take the example of a pack of yoghurt whose statutory temperature is +4°C. A temperature reading of +5.5°C in contact with the packaging is accepted. The pack of yoghurt is therefore considered compliant. If the reading had been +6.1°C, a measurement of its core temperature would have been necessary and it would have had to be no more than +5°C.

Thinking about your cold logistics means paying attention to several parameters that go beyond simple issues of keeping the goods at the right temperature. It involves thinking in a global way and making choices that could have an impact on operators’ working conditions and the cost-effectiveness and sustainability of the model applied.

Finally, we should not forget the aim of supporting you with your cold logistics is to help you set up an eco-system that is cost-effective, efficient and responsible. There is, of course, no one solution, but multiple possible combinations depending on the objectives you wish to attain.

For more information, read our article on food refrigeration.