Talking about cold in the fish sector is very important. The value of fish worldwide, according to "Statista", is constantly growing and is expected to go from about 120 billion dollars in 2016 to exceed 155 billion in 2023. Refrigeration is therefore a fundamental element to guarantee quality and respect hygienic and sanitary conditions, as well as to enhance the taste characteristics. But what is the "right cold"? How to insure it and how to manage the whole cold chain? Valentina Tepedino, veterinary surgeon specialized in the fish sector and national contact point for the fish sector for the Society of Preventive Veterinary Medicine, answers these questions. Not only that: she is the general manager of Eurofishmarket, a consultancy, training and information company on fishing and aquaculture on the environment. She has been scientific consultant for Rai tv and also for Mediaset tv for broadcasts such as "Linea Blu" or "Pianeta Mare", but also for other TV and radio broadcasts.

Valentina Tepedino, veterinary surgeon: "The management of the cold chain in the fish sector is not easy."

What are the best refrigeration solutions in the fish sector?

The fish sector is very complex and also the management and guaranteed maintenance of the so-called cold chain is not easy. From fishing to distribution to the table of consumers, the way is really very long and the steps could be many and very different from each other. To better explain I give the following example. If the fish is caught on the boat there is usually a refrigerated cell where the product is kept in water and ice, upon disembarkation generally in disposable polystyrene boxes and ice in the various destinations (market, wholesale, retailer, shop, restaurant etc.) and therefore it will be displayed on ice in fishmongers or it will be worked and stored in the refrigerator in restaurants. In my experience I can say that more than the equipment, useful to guarantee the cold chain, the management of the equipment and the fish in relation to them counts.

What are the main problems in the sector?

They are determined by poor management regarding what has been said: unrefrigerated fish immediately after fishing, fish left too long parked between one supplier and another or from the cell to the counter or from the counter to the restaurant at the customer's home. So, in my opinion, the most sensible innovations are those that combine the control of traceability with the management of the cold chain: therefore refrigerated cells that monitor the temperature by recording it automatically, refrigerated vehicles or isothermal containers that guarantee as much as possible an upstream control on the correct maintenance of the cold chain. There are not many innovations in this regard relating to the fish sector and this often entails a shorter duration of the commercial life of the products and a consequent waste and economic damage for the whole chain.

For each fish variety, is it good to think about a specific type of refrigeration?

In reality, the ideal would be to be able to shorten the supply chain more and more in the future in the sense not of the Km (mile) zero, difficult to achieve, but drastically decreasing the steps between manufacturer and distributor. I repeat: it is especially in the passages that there are usually sudden changes in temperature that are not optimal for the life of fish products. In addition, market surveys are showing ever-greater growth in ready-to-eat and ready-to-cook fish products that will surely be managed in the future with the so-called "smart labels" to find out if they have had temperature changes from production onwards. Fish as big as yellow fin tuna and swordfish arrive increasingly processed in slices and strands, vacuum-packed or in a modified atmosphere. Surely it would also be necessary to do more research on the ideal conservation systems to extend the shelf of fish products without necessarily using additives in addition to the product. A few years ago, together with the University of Veterinary Medicine of Padua and with the Society of Preventive Veterinary Medicine, we carried out a research to better understand the different duration between a slice of yellow fin tuna in a modified atmosphere (atm) and a vacuum packed one. It has been shown that, of course with the right proportion of the various gases, yellow fin tuna in atm has a longer shelf life. These searches are important because in addition to finding useful solutions to keep the product longer, they must also ensure that the external appearance is kept as pleasant as possible. A tuna that becomes dark brown even if the ideal would be to shorten the supply chain more and more in the future in the sense not of the zero (mile) mile, but drastically decreasing the steps between producer and distributor, especially in the Critical thermal zi refrigerated well will hardly find market. Similarly, a red or purple shrimp or whatever it may be, even if well refrigerated shortly after death, will have a sort of black spot on the head and will not be very salable and hence the addition of permitted additives. The ideal would be to be able to market live crustaceans, but here then we should face the important issue of the management of live fish products which is still much debated as there is no clear guideline by the competent official bodies on the matter and ad hoc legislation. Molluscs, for example, must be marketed alive and viable and so must be at the time of purchase. For these products, refrigeration is carried out with ventilation systems useful to avoid direct contact on the ice which would cause their death. "The ideal would be to be able to shorten the supply chain more and more in the future in the sense not of the Km (mile) zero, but drastically decreasing the steps between producer and distributor, especially in critical temperature changes."

In general, how should cold be used?

The ideal would be to be careful to "dose" the cold equally in the whole box and on all the products contained and so should be also during their display on the counter, making arrangements useful for this purpose without making piles and creating a good "game" with ice. The quality of the ice or rather its size and cut also has its importance as well as the way it is placed around the product.

Is a certain cooling action necessary or preferable for storage up to the sales counter?

The most important thing would be to avoid interrupting the cold chain. For many products, incorrect management could decrease their commercial life and ruin their original sensorial and nutritional characteristics. In some species belonging in particular to some families of fish such as anchovies, sardines, the different species of "tuna" or tuna or tombarelli or mackerel. Instead, an interruption of the cold chain could lead to much more serious consequences, affecting the health of the consumer. In fact, the aforementioned and other species, if handled poorly, could cause the so-called mackerel syndrome with the degradation of the histidine normally contained in them in histamine. A fundamental requirement to avoid the formation of histamine is the rigorous respect of the cold chain.

What are the sector's evolutions in its needs for optimal fish conservation?

In the future, technologies will be increasingly studied and applied to provide ready-to-use fish products transformed in order to last longer. Furthermore, the supplier of fish products that will be able to provide guarantees, registrations or certifications on the correct maintenance of the cold chain along the entire supply chain will become increasingly decisive and reliable. An innovative product that I find very strategic both to the aforementioned both for the fight against waste and for environmental sustainability are the "intelligent" isothermal containers that is those that combine electronic microsystems that can monitor and therefore to be able to control the products along their entire path. One of the most innovative solutions is based on an App and a WebApp that dialogue to collect, store and manage traceability data. This "dialogue" takes place thanks to RFID technology, which is increasingly used in logistics and distribution. Thanks to the appropriate cloud, users can consult the data transmitted by their Apps, perform searches with various filters and export the data to produce statistics. The most innovative products are also able to print the "Certificates of Conformity to the Traceability system". It is a document that certifies the traceability of the operation to trace in detail the shipments and deliveries of meals and food, monitoring them throughout the distribution chain. This technology is strategic in deliveries of collective catering dedicated to school and hospital canteens, but also for restaurateurs who today often do not use refrigerated vehicles for fish supplies. Cold-related technologies such as freezing at very low temperatures are also beginning to make headway in the fish sector and are being studied for the cost / benefit assessment especially on yellow fin tuna steaks.

This text is taken from the article "The good fish at the table starts from a good cold chain" published on Eurofishmarket of December 2019 and written by Valentina Tepedino, Veterinary Physician.