February 3, 2021

Why Proper Cold Chain Makes or Breaks Your Fish Dish

Finland is known for high quality products and life quality. Even here, in the most populated areas, it takes the fish three to four days on average to reach the market after it has been caught. By the time the consumer gets their hands on the fish, it might be a week old. At that point, it’s a stretch to call it “fresh”. The lack of freshness and long time from sea to your plate are reasons for low quality fish. According to recent research, a quarter of fish samples taken from “fresh” fish are of low quality. The sad thing is that the results have not improved in over a decade.

Picture this situation: you’re shopping for groceries, stop at the fish market, and notice your favorite fish on sale. Asking for the delivery date of the batch yields the vague answer of “a couple of days ago”. This obviously doesn’t help you at all, since it tells you nothing of how long the goods remain usable.

Finland is known for high quality products and life quality. Even here, in the most populated areas, it takes the fish three to four days on average to reach the market after it has been caught. By the time the consumer gets their hands on the fish, it might be a week old. At that point, it’s a stretch to call it “fresh”.

The lack of freshness and long time from sea to your plate are reasons for low quality fish. According to recent research, a quarter of fish samples taken from “fresh” fish are of low quality. The sad thing is that the results have not improved in over a decade.

Already a decade ago, Finnish food authorities determined that fresh fish is said to stay usable. The declaration was not heeded, and globally markets sell fish past its true best before dates.

Bringing fish from water to the market

The fish’s journey to your platter starts with a fisher or a fish farm. A fisher might clean the fish already in their boat, a dedicated space, or deliver them onwards without cleaning them. In the case of a fish farm, the fishery sends the fish directly to a processing facility for cleaning, chopping, and packaging.

From the processing facilities, the fish is delivered to wholesalers, restaurants, and retailers. Each of these businesses is responsible for the quality of their fish themselves, but the quality assurance is left mostly to them as well, while the processing facilities are required to take samples regularly. The larger a processing facility, the more samples should be tested.

For retailers, wholesalers, and restaurants, the quality assurance has more to do with health code monitoring from the authorities’ perspective. In Finland, the quality control includes monitoring the appearance and temperature of incoming fish deliveries. Monitoring of storage temperatures is another crucial element, as are general hygiene measures. 

While a lot of the quality control is left for the business to handle themselves, authorities may make occasional checks to ensure that safety standards are up to the expected level. The checks often include taking samples of the product itself, but also storage temperature and cleanliness of the space are performed regularly. The most common issues tend to be in the general hygiene and maintaining and proving that the product is kept within acceptable temperature ranges.

A warning is not usually enough to bring quality up.  While you might think that after all, who would want to provide substandard goods to their customers, samples taken show issues. In Finland, up to 46% of all tested fish samples show at least some warning signs of low quality. On the other hand, the line between acceptable and low quality fish is a line drawn in water.

man holding a fishnet
While more ethical, wild fishing usually leads to longer sea-to-mouth journey than fish farms.

Cold chain secures safe-to-consume fish

Problems can start as early as the fishery. From the moment the fish is caught, the cold chain has to be maintained all the way until it is finally prepared for food. As sensitive as fish is, it also requires a high hygiene standard from all parts of the distribution chain between the fishery and the consumer.

The cold chain can be broken in many places: on the way from fishery to processing, from processing to sales businesses, or from business to home. If the temperature of the fish rises too high, the speed of spoiling speeds up. This means that at the end, the business selling the fish is responsible for its quality.

Do-nots of selling fish

As a temperature-sensitive product, fish requires the upkeep of cold chain throughout its journey from fishery to consumer. Here are some practical notions of what not to do when selling fish:

Do not pack too much fish to be on sale at the same time. The refrigeration available on fish counters can only handle a limited amount of fish. Extra fish packed on the counter does not stay cold whereas an actual refrigerator in the backroom would.

Overstuffing counters is often done intentionally, because a counter full of fish looks more enticing. An empty or near-empty counter might spawn the idea that all the good fish is gone and only the last fish of lowest quality remain. In truth, the fish closest the counter’s bottom (and therefore cooling) may well be the safest to eat.

Do not mix old and new fish. When bringing fresh fish from the backroom to the counter, keep the fish apart with plastic film to avoid contamination by contact. In general, it’s best to keep different batches completely separate.

Simply placing the fresh fish on top of the old ones might seem like the easy way out, which it is. However, that way you risk contamination as the old batch might already have developed bacteria that doesn’t yet exist on the new batch. As a best practice, it’s best to place the new batch on the bottom closest to the cooling, place a separating plastic film on top of it, and finally place the old batch back on the plastic.

Three days on the counter is a long time for a fish

While often the case, fish shouldn’t stay on sale for more than three days. To ensure that the fish is safe to consume, its quality needs to be monitored daily. The date of harvesting and expiration date give a good idea of how long the fish should be usable. Another important bit of information is the date when the fish was first put on the counter. 

Sense of smell can help a lot when it comes to choosing fish as well. For instance, in Norway, known for its fishing industry, fish counters rarely smell of anything. In many other countries, anyone can recognize a distinct smell of fish. 

A large part of the quality control in markets is up to the person running the fish counter. On the other hand, they need to ensure that high quality goods are being sold, but have to balance to avoid waste. In worst case scenarios, the fishmonger might be pressured to stretch the time before they throw out old fish. 

Especially supermarket chains can be risky, since working at a fish counter often requires no specific education. With good luck, the counter is run by someone well versed in fish and food safety, but in many cases, just any employee might end up working the counter.

The bare minimum for fish food safety should include constant monitoring of the temperature levels and basic food hygiene. Collecting data points multiple times a day allows the business to also build an understanding of what contributes to their waste on the counter. That knowledge in turn helps improve the process for both the business’ and customer’s benefit.

brown cookies on black table
Fresh fish is an absolute necessity for delicious sushi.

What makes fish “low quality”?

Fish becomes low quality when the amount of harmful bacteria rises above acceptable levels. The amount of bacteria increases over time in any case, but an effective cold chain mitigates a lot of the increase. As a result, the most meaningful elements of fish reaching the consumer safely are the time-to-sale and storage temperature until the sale. 

Should the temperature be too high, the bacteria multiplies much faster. On the other hand, even a low temperature is not enough to keep the bacteria at bay, if the fish stays on sale for too long.

What makes it all challenging for wholesalers, restaurants, and retailers is that each and every processing facility has their own practice for determining the expiration date for the fish. Even fish caught or harvested the same day might have multiple days’ difference in expiration date depending on the facility.

The acceptable levels of bacteria are the same for everyone, but each facility can determine their “own” expiration dates. A good practice is to test storage life regularly to determine an accurate expiration date.

Different fish and processing methods also affect the storage life of the sold product. Some filets might stay usable for only a week from processing, while the expiration date for others might not be until ten days have passed.

Since the long supply chain of fish includes multiple steps, it’s often difficult to determine who is at fault if something goes wrong – especially if the issue isn’t noticed until late at the distribution chain. Without end-to-end monitoring, no one is willing to take the blame either.

What you can do when buying fish

When you’re looking to buy fresh fish, you might note that getting precise information on harvest expiration dates might be difficult. In some cases you might need to ask for the information at the counter as it’s not clearly shown anywhere. When asked, the person at the counter might hesitate, give only the date the store received the fish, or not even know.

In the best case scenario, the harvest and expiration dates are clearly shown near the fish. Of course, even then the expiration date marked is based on the storage life determined by the processing facility or wholesaler.

Here we return to the variation on estimated storage life – for different fish the time it stays fresh is different, and different authorities give different estimates based on their tests. By average, fish deliveries reach their destination in stores three days after harvesting – meaning the earliest recommended expiration dates are the same day the fish arrives at the store. On the other hand, some fish may stay “fresh” for an entire week at the store.

For the consumer, using the freshly bought fish within two days would be best. While store cold storage temperatures stay at a steady temperature around 2°C, home refrigerators are usually not that cool – not that they should be, either.

A consumer might occasionally end up in the unfortunate situation where the store does not display the harvesting info at all, and has to trust that the all of the fish on sale is of high quality.

Where does the quality fish come from?

In Finland, Norwegian salmon tends to fare well in tests. Known for their fish, the Norwegian fishing industry has developed a fast, efficient distribution chain. In addition to the efficient supply chain processes, the fish produced in fish farms tends to be more hygienic than fish harvested from the wild. In the case of fish farms, the fish is harvested, processed, and frozen to be packaged fast. 

The longer fish remains on sale, the worse its quality becomes. A week in the store is enough for the fish to go bad.

And when the fish quality goes up, the likelihood of harmful bacteria goes up. Raw fish poses risks that cooking removes. Making foods that include raw fish, such as sushi, is particularly risky when using old fish.

Harmful bacteria like listeria can be a serious threat to certain groups. While healthy people might only suffer minor symptoms, the elderly and pregnant face much more grave dangers. A listeria infection spreading in the system can lead to serious complications, including meningitis. Fortunately listeria is very rare in fresh fish, but week-old fish is riskier.

Another dangerous bacteria is common in vacuum packaged fish products. The botulinum bacteria Clostridium Botulinum thrives in environments that lack oxygen – making vacuum packaged fish an excellent breeding ground. A botulism caused by the bacteria can be lethal.

The good news is that both listeria and botulinum can be destroyed by cooking the fish.

gray knife and orange fish on wooden chopping board
Fresh fish makes the tastiest dish – old fish, if usable at all, requires a lot of seasoning.

Not all old fish is dangerous – it only tastes bad

If you face a situation where you only have a week-old fish left, you can often still salvage it as a food by cooking it properly and making a well-seasoned casserole dish out of it. 

Fresh fish is a valuable ingredient. The price you pay for fish would warrant for quality goods, but that is not always the case. Freshness is a major factor in how the fish tastes and smells. The top restaurants can well decline shipments of poor quality fish.

Like in many other things, buying fish from an acquaintance is usually a good idea. A personal connection to the seller can get you fresher fish, and your request to fetch the freshest fish from the backroom freezer might be better received than if you were asking a stranger. 

Of course, the request can always be declined by the seller as well, but in that case it might often be a good idea to buy your fish elsewhere. Having the freshest possible fish is particularly important if you’re making sushi or something else that features raw fish.


The freshness of fish is essential for all parties involved. For the producer and distributor, poor quality can cause severe problems and reputation damage if their products cause bacterial infections – which can be fatal for the consumer. 

As for all sensitive food items, I highly recommend investing in a temperature monitoring method that allows you to track the quality of your products from the moment you get your hands on it to the moment it leaves them, be the latter towards your mouth or to that of a customer. 

Logmore’s solution allows you to recognize patterns in inefficient routes, malfunctioning cold equipment, or brings an extra layer of security to your fish counter. Interested? Contact our sales here.

Did you enjoy the article? Talk to us or keep on reading

Want to
your supply

Want to
your supply

Let's talk