Fish Oil Production , Fish Oil Supplements

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Fish oil around the world

Over the past decade or so, fish oil production has been steadily decreasing across the world but at the same time, the demand for fish oil has been increasing. Fish oil is required for both animal feed and for human consumption. Currently, around one million tonnes of fish oil is produced annually. The main producers of fish oil are Peru, Chile, the USA, Japan, and Scandinavian countries, however, Peru is by far the world leader and contributes around a third of all fish oil stocks globally.

The biggest exporters of fish oil are Peru, Chile, Iceland, Denmark and Norway and the two countries importing most of the Peruvian fish oil are Denmark and Belgium who between them take around 50%.

Type of fish used for fish oil

Although fish oil can be produced from fish caught in any sea, anywhere in the world, fish oils that are produced from the coastal waters around South America are particularly in high demand as they are relatively low in toxins compared to fish caught elsewhere.

The fish containing the most toxins, like mercury, dioxins and PCBs, are the larger predatory fish that have longer life spans, for example Shark, Swordfish and Tuna. These fish eat smaller fish, which then eat smaller fish, and so on, and as they have quite long lives the level of pollutants in their bodies’ increases cumulatively so that over time the amount of toxins concentrated in these types of larger fish can be extremely high.

The type of fish is also important for the production of fish oil destined for the supplement market because Omega 3 nutrients are only really concentrated in cold water fatty fish and not in white fish. Ideally for fish oil production the fish should be smaller, with a shorter lifespan. This is partly so that the fish can reproduce faster and stocks can replenish quite quickly and also because there is less build up of toxins. So for example, anchovies, sardines, and horse mackerel are popular fish for fish oil.

Although there is a large amount of Omega 3 nutrients in Shark and Tuna, these are also eaten as foods so fish oil made from these types of fish tends to be produced from the left over parts of the fish that aren’t destined for the human food market, for example off-cuts, the intestines and the eyes.

So to sum it up, the ideal fish for fish oil production destined for the health food supplement market are smaller whole fatty fish that can reproduce quickly and which live in relatively unpolluted colder waters. This is perhaps why the Peruvian anchovy industry is such a successful and major producer of this kind of fish oil.

The Peruvian Anchovy Industry

It was in the late 1940’s that anchovy production in Peru really started to take off. Sardines had been overfished in California and when production was no longer viable, some of the equipment was sold to Peru allowing the industry in Peru to boom.

Obviously with the same technology and desire to profit from the fish stocks there was also the risk of overfishing in Peru and in order to try and reduce this risk the Government of Peru tried to ensure that anchovies were only fished at levels which could be sustained year after year. Several studies have shown that the sustainable amount of anchovies that can be harvested indefinitely is somewhere in the region of nine and a half million metric tons a year. However, the Peruvian industry with its efficient fishing fleets, sophisticated technology and willing workforce, could actually be capable of producing five times that figure if they wanted to. As such, the fishing industry in Peru is heavily restricted in order to preserve future generations of anchovies.

Some of the measures the Government of Peru introduced in the early days were a shorter working week and a shorter season in which anchovies could be harvested. As the Peruvian anchovy industry became more efficient and technology improved, more and more measures were put in place to try and keep the annual harvest down.

In the 1990’s a major challenge was the fact that the fishing season only lasted for about 7 weeks of the year which put an enormous amount of pressure on fleets to catch the anchovies in that space of time. Competition was great between fleets and the bays were filled with ships and as a result working conditions were not as safe as they could have been.

Then in 2009 the Peruvian government introduced new measures. The fishing season was increased to twenty seven weeks and an individual quota system was introduced for each boat along with more rights for the workers. It is generally agreed that this was a positive move for the industry because it meant that not so many fish were caught in such a short space of time. Working conditions have also been a bit safer and there haven’t been so many boats around at the same time all competing for the same resource. However, it still hasn’t been enough to prevent declining stocks.

El Nino

One of the challenges facing the Peruvian fishing industry is the impact of the El Nino Southern Oscillation phenomenon or ENSO. This change in the conditions in the water takes place roughly every three to four years and it negatively impacts on the amount of anchovies harvested. No one yet really fully understands what is happening and why it happens but fishermen around the coastal areas of Peru have been aware of the phenomenon for centuries. So what happens during an El Nino?

Well normally, when there is no El Nino, what happens is the winds push the warmer water away from the coastal areas and this causes something known as ‘upwelling’. An Upwelling is a current of cold water that takes the space left by the warmer water that has been pushed out by the wind. This cold water current is very rich in nutrients and provides food in the form of phytoplankton for many species of fish, including anchovies.

Every few years the pattern of the wind changes and instead of cold water welling up it is warmer water containing very few nutrients that wells up. This means the surface temperature of the water can rise by up to two or even three degrees and this has an enormous knock on effect on the ecosystems in the area and also on fishing hauls.

Without an adequate food supply near the surface, Anchovies basically move down deeper in the ocean and the fishing nets are no longer able to reach them. As a result of the anchovies moving position the food supply for the some of the marine birds that feed on anchovies is also removed which results in the birds disappearing for a while too.  Bird droppings from some of these birds’ acts as a profitable and effective fertilizer for farmers but during an El Nino the population of the birds can be decimated along with the amount of fertilizer available for collection.

Recent measures

 Last year the government of Peru implemented even stricter measures in order to try and protect future supplies of anchovies. They have basically banned fishing across a whole strip of coastal waters and larger boats are no longer allowed to fish within ten miles of the coastline although in the south of Peru the limit is reduced to seven miles. They also slashed the quota to the smallest level it had ever been.

Demand for Fish Oil

The demand for fish oil has been steadily growing over recent years and this is unlikely to stop in the years to come.  Demand for fish oil for human consumption is on the increase and that is not showing any signs of slowing down and understandably so.

It is now well accepted that Western diets are deficient in important Omega 3 fatty acids such as Eicosapentaenoic acid and Docosahexaenoic acid. There is also a growing awareness of the health benefits to be gained from these Omega 3 fatty acids, such as a reduced risk of cardiovascular disease, mental health problems and inflammatory conditions like arthritis, but the list of potential health benefits is growing all the time. This has resulted in an ever increasing demand for fish oil capsules that are highly concentrated in these Omega 3 fatty acids.

Coupled with that is the knowledge that eating too much fish isn’t a viable option for getting enough Omega 3 nutrients in the diet due to the amount of pollution in the oceans because of course these pollutants are also in the fish. Governments and health professionals are aware of the double edged sword here and recommend that people still eat fish but limit the amount to two portions a week.

As the demand is increasing and at a time that world production of fish oil decreasing, this means that the price of fish oil is likely to rise and will no doubt continue to rise in the future as competition for supplies increases. On saying that though, according to Globefish, fish oil prices are expected to remain stable during the first three months of 2014 but after that though, no one seems to be sure and everything could change.

Types of Fish Oil

When fish oil first appeared on the market all those years ago, it was in a much cruder form than it is now. Think of the foul tasting Cod Liver Oil that your grandparents had. Cod Liver Oil is produced from the liver of the fish and this is where the Omega 3 fatty acids are concentrated. However, also stored in the liver are all the pollutants as well as high levels of Vitamin A. Too much of this fat soluble vitamin can be toxic to humans and pregnant women are advised to avoid this type of fish oil altogether.  In fatty fish, Omega 3 fatty acids are stored in the darker meat of the fish and not just in the liver and the fish oil produced from this type of fish doesn’t contain excessive amounts of vitamin A.

Since those early days of crude Cod Liver Oil and then the discovery by Danish Scientists back in the 80’s about the protective benefits of Omega 3 fatty acids, countless studies have been carried out showing just how beneficial fish oil can be for health. This awareness resulted in fish oil becoming the new ‘must have’ for health and fish oils started appearing in supermarkets everywhere. These ‘standard’ type fish oils contain around 18 percent EPA and 12 percent DHA.

Recently though, there has been a much bigger demand for more concentrated fish oils containing much higher amounts of Omega 3 fatty acids. Production of this type of fish oil requires more sophisticated production methods which can produce superior quality oil but it is also a more expensive fish oil.

How is fish oil produced?

Think of fish as a mixture of solid type flesh and oil and water. The oil in the fish consists of something called triglycerides. Triglycerides can be described as a glycerol backbone with three fatty acid groups attached to it. Also in the fish of course are some undesirable ingredients like Mercury, PCBs and Dioxins.

When producing fish oil, especially concentrated fish oil, the fatty acids and all the other ingredients need to be separated out into their individual parts so that some parts can be removed and others retained. There are several ways of doing this, each with their own advantages and disadvantages. The dilemma facing the fish oil producer is how they can do this as efficiently and as cost effectively as possible without damaging the oil.

There are basically two main methods of sophisticated fish oil production and the first is Supercritical Fluid Extraction (SFE) along with Supercritical Fluid Chromatography (SFC), and the second is Molecular Distillation (MD). Regardless of which processing method used, the fish have to go through a process of cooking and pressing before any refining and further processing can take place.

‘Cooking’ the fish

The purpose of the cooking phase is to ‘coagulate’ and separate out the protein part of the fish from the oil and water part. These days this is more often than not carried out in a steam cooker with even heat distribution. The solid parts are then used for fish meal. Once the fish has been cooked the oil is then extracted, often by centrifuge. Centrifuge is a process whereby a machine with a rotating container applies centrifugal force in order to separate the contents, i.e. oil from water, liquids from solids and so on. The oil and water are separated from the liquid parts and the oil is then “polished” which basically means it is cleaned up, but this is a much more basic form of cleaning and nothing like the processes that are used for eliminating toxins.  Most of the oil at this stage of production is destined for use as animal feed.

Until not so long ago the general consensus was that in order to obtain the best results from the cooking phase it was necessary to subject the fish to extremely high temperatures. However, recent research shows that this is not the case and the oil can be ‘freed’ up at much lower temperatures. It has also been discovered that it doesn’t take very high temperatures for the solids to coagulate either. Therefore, most fish oil producers have come to the conclusion that there is no point of using really high temperatures when the same effect can be achieved at lower temperatures at a faster speed and with less expense.

After cooking and pressing, a relatively small amount of oil destined for human consumption then goes for further processing and this involves bleaching and deodorizing at temperatures of up to 200 Degrees centigrade. This fish oil can then be put into capsules and sold as a fish oil supplement as it is or it could be further processed to decontaminate and purify the oil a bit more. Obviously this would incur greater costs and this cost would ultimately be reflected in the price of the fish oil. You certainly get what you pay for here.


In order to produce concentrated and purified omega 3 fish oil supplements it is necessary to remove the shorter chain fatty acids by converting them into either free fatty acids or ethyl esters. To convert them into ethyl esters, ethanol is used at temperatures of between 80 and 90 Degrees centigrade and this frees the fatty acids up from the glycerol backbone in the oil.

There are three ways that the fish oil can be decontaminated further. The main challenge here is to be able to remove the pollutants and undesirable components without altering the quality of the oil and the nutritional value of the oil.

One of the most popular ways that contaminants are removed from fish oil is by absorbents such as activated carbon. Activated carbon is carbon that has been treated so that it becomes highly porous and therefore is able to absorb undesirable elements in the oil.

The other two more sophisticated methods of purifying and processing fish oil are molecular distillation and supercritical CO2 extraction.

Molecular Distillation

In this method the fish oil is put into a vacuum and heated to temperatures of between 140 and 160 degrees centigrade. At this temperature the free fatty acids evaporate and what is left is oil that is concentrated to contain about 55% omega 3 fatty acids. This type of oil is now readily available on the market as fish oil today along with the cheaper 30% Omega 3 Oil.

How it works is that based on molecular weight, the various components can be separated. So because EPA, DHA and all the undesirable toxins have different molecular weights, they can be identified and separated out.

However, there are some disadvantages to using this method. Really high concentrations of Omega 3 fatty acids aren’t really possible as it would involve reheating and reheating the oil over and over again to obtain only slighter higher concentrations and this isn’t desirable. On a more positive note, this method is highly effective for decontaminating the oil and removing all the undesirable toxins and pollutants.

Something that should be mentioned here is a process called Flash Distillation (FD). This is also sometimes carried out and it does exactly the same thing but the process is carried out using steam as opposed to using a vacuum.

 Supercritical CO2 Extraction

Carbon Dioxide is stable and is normally used in both Supercritical Fluid Extraction and Supercritical Fluid Chromatography. Supercritical Carbon Dioxide is Carbon Dioxide in a fluid state above its critical temperature and critical pressure. When temperature and pressure are increased beyond the standard temperature and pressure for Carbon Dioxide to a point above the critical temperature and pressure for Carbon Dioxide, the carbon starts to behave differently in that it expands in the way a gas does but still has the density similar to a liquid.

We need to explain what a supercritical fluid actually is though. It can be described as any substance that is above its critical point in terms of pressure and temperature.  It is not strictly a normal state liquid, and is not solid and it is not a gas but a “fluid” that is neither solid or gas but is in between both these states.

This process is carried out on oil that has previously been subjected to molecular or flash distillation. This method uses much lower temperatures in the region of 40 to 50 Degrees centigrade in order to extract and concentrate the fish oil. No organic solvents are used in this process. It is an excellent technology for concentrated Omega 3 fish oil as concentrations of up to 99% is possible.

The extraction can be rapid and selective and simply by lowering the pressure and controlling the density, any extracted material can be recovered.

Advantages of CO2 Extraction


Lower temperatures are possible which preserves the integrity of the oil

  • It is safe as it is non inflammable and non toxic and it doesn’t use any solvents
  • The separation of substances within the oil is particularly easy
  • There is very little waste with this type of production method
  • There is minimal impact on the environment with this production method


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