The ancient Norse Vikings were consumers of liver oils, in particular codfish liver oil, Chimaera monstrosa (ratfish) liver oil, and shark liver oils. Codfish liver oil was used for the maintenance of general health, particularly during the cold months ending in "r". These months are characterised by low sunlight intensity and an increased risk of hypovitaminosis D (vitamin D deficiency). Such a deficiency can have tragic consequences in light of the fact that vitamin D has been shown to play very important roles in brain, heart, immune system and bone health. During the winter months in the northern climes, people are unlikely to be able to synthesise enough vitamin D via ultraviolet-B rays from sunlight striking the skin and triggering vitamin D synthesis. So having a diet that is rich in oily fish, and consuming fish liver oils, would have given the Nordic people a natural supply of this all important vitamin during the winter months.

Unlike codfish, Chimaeras are mainly confined to the very deep waters and as such were not in plentiful supply for the Vikings, who considered the oil from their liver to be a rare and precious gift from the sea, naming it “Gold of the Ocean.” This oil was reserved for therapeutic purposes including the treatment of general debility, infections, irritations of the respiratory and alimentary tracts, and glandular disease. It was also used to reduce inflammation and promote the healing of wounds.

The ancient Norse Vikings and fishermen were well-versed in isolating liver oils and used two very rare, and largely unknown, methods. They had a deep understanding of nature, since they lived in the wild, and both methods were based on nature’s principles. We have described and illustrated both methods for you below.

Method 1

Very soon after the fish are harvested from the wild environment of the Norwegian Fjords, the livers were carefully removed. The fish liver must have a specific appearance and come from a fish of a specific age otherwise it was never used for the production of liver oil. The picture below shows a member of our team removing a fish liver. You can also see at the bottom right hand side of the image a ceramic knife. We never use metal to manipulate the livers for fear of oxidation which can adversely affect the final quality of the product. Metal is definitely a no-no!



The ancient Nordic people rendered their fish liver oil from healthy fresh & wild livers, and the picture above is a perfect example of such a liver. The quality of fish liver oil is highly dependent on the quality of the liver just like the quality of olive oil is dependent on the quality of the olives. A fresh ratfish and codfish liver is pale with an almost cream-coloured appearance. It should also be beautifully plump and very soft to the touch. Such a liver abounds with fine quality oil that appears perfectly pellucid and pale-coloured with only a mild fishy taste.

After the fish have been dead for only a short-time, changes begin to take place in the livers delicate structure which can adversely affect the quality of the oil. Ideally, the rendering process should begin immediately following the removal of the fresh livers and at least before putrefaction has commenced. This results in the lightest coloured oil. If rendering is delayed for a prolonged period of time a dark coloured oil is produced which is the result of impurities present within the oil which have no relation whatever to the goodness of the oil.

Once the livers were isolated, the raw oil contained within them was then “captured.” The process used to capture the oil was remarkably simple and probably has its origins even before the Viking era. The Ancient Nordic people observed that fish livers vary in appearance, size and texture depending on the seasons etc. These people were very much in touch with nature and found that by imitating the Norwegian seasons and exposing the livers to these seasons, the raw oil naturally separates from the livers WITHOUT any intervention whatsoever! For example, by allowing fresh fish livers to freeze in the cold Norwegian weather and then moving them to a room which is at the temperature of the Norwegian summer months, the livers will begin to thaw and at the same time the raw liver oil naturally separates from the livers. As the oil separates from its liver, the liver changes from a creamy coloured appearance to a reddish-brown colour.

This ancient method based on nature’s principles captures & preserves the freshness, nutrients and health benefits of the oil. The nutritional content of an oil produced using this age-old method is identical to what you would find in the liver oil of a ‘living’ wild codfish. And we make no attempt to alter the nutrient levels. Nature dictates the nutrient levels in our oils. That is how it was for our ancestors and that is how it should always be.



Method 2

The other rare method employed by the Norse Vikings, and used on special occasions, involved the whole fish. This method eliminates the need to remove the livers.

The ancient Norse Vikings would simply hang a ratfish up by its long tail, and after a period of time the liver oil would start to drip from the end of its nose. We have replicated this process for the very first time for all to see. This has never been shown before.

1. Below is a picture of a ratfish, freshly caught by the Rosita team, with its long threadlike tail tied with string.


2. The ratfish is then allowed to hang freely by its string for a period of time.


3. After a certain amount of time has elapsed, oil from its large oily liver will then begin to accumulate around its nose. The picture below shows this. The oil is remarkably clear, pale-coloured and sweet smelling.


4. The oil would then begin to drip and the Vikings would collect this very special oil, their Gold of the Ocean, and consume it during times of stress and whenever they saw fit to do so.

The oil produced using method 2 was held in particular high regard by the ancient Nordic people and Norse Vikings who believed it to be extremely potent, not only containing the therapeutic elements present in the liver but also those from other organs of the fish as well. Its use was therefore reserved for special occasions.


Rosita Ratfishoil®
Glein, N-8820 Dønna, Nordland - NORWAY