Fishy business: Sirio discusses fighting odorous oxidation in fish oil supplement production

20 Sep 2021 --- Sirio is expanding its range of manufacturing techniques that can combat the issue of oxidation during fish-oil based nutraceutical production – something that can lead to highly unpleasant odors and tastes.

Jan Jakub Stasko, Sirio Europe’s head of formulation, discusses this common industry problem with NutritionInsight and explains how modern techniques can prevent consumers from consuming health products by foul-smelling supplements.

Marine oils are highly susceptible to oxidation due to many polyunsaturated fatty acids (PUFA) they contain, explains Dr. Stasko.  

“If unchecked, oxidation can lead to formulations having an unpleasant or even fishy smell. While there is no clear evidence that high oxidation levels are harmful to health, there are no official limits either,” he says. 

While brands and manufacturers are currently setting their own standards, the secret to reduced oxidation is to keep these PUFAs away from oxygen, heat and light as much as possible, continues Stasko. 

The move toward flavored gummies is an effective method in preventing foul-smelling oxidation in fish oil supplements.Measuring oxidation
The key measurements used to assess oxidation by the nutraceutical industry are peroxide value (PV) and anisidine value (AV), along with a composite of both, called Totox.

“We use the PV test to measure hydroperoxides, which are primary oxidation products in fish oils and take this as a measure of the quality of the initial raw material,” explains Stasko.

A PV of 10 is typically the accepted level within most of the industry. However, some customers insist on a starting level of between 3 and 5 within a softgel.  

Starting from a low threshold is important if the PV of the formulation is not to exceed a level of 15 or 20 during its shelf life. Additionally, other factors, particularly packaging, also play a key role in maintaining a low target level.

The secondary stage of oxidation occurs when these hydroperoxides decompose to form other compounds, in particular aldehydes, which give the fish oil a telltale rancid smell. To measure secondary oxidation the AV test is used.

Targeting oxidation 
In order to prevent oxidation and its impacts on user experience, it is essential to start with the highest quality ingredients, says Stasko. 

“After this, it’s down to the skill, experience and production methods of the formulator to ensure the initial quality carries through to the final product.”

“The fact is that all oils are prone to oxidation, and you can never prevent it completely. You can, however, make efforts to reduce it at each stage of the production process.” 

“For example, during encapsulation, oxygen has the potential to come into contact with the oil. Reducing exposure here helps to ensure we can deliver a product that maintains a low level of oxidation during processing, thereby delivering a longer shelf life.”

Blenging fish oils with other ingredients can increase oxidation, explains Stasko.Sirio Europe has developed a specialized process that uses protective gases for the preparation of the fill material prior to encapsulation. Most nutraceutical manufacturers will use nitrogen to ensure the mixing tank is free of oxygen, but Sirio says it “goes a step further” by using argon. 

“Before adopting this inert gas as our standard operating procedure, we thoroughly researched the benefits of its use at the time of mixing. We found that it had a real impact on the final quality of the product, since it is even more effective than nitrogen in protecting the oil from oxidation,” he asserts.

Omega 3 challenges 
The most common fish oil products are those containing omega 3, Stasko comments. 

“Typically, these will contain 500 to 1000 mg of fish oil, often with the addition of oil-soluble vitamins. The antioxidant vitamin E (tocopherol) is a popular addition – which obviously comes with the benefit of protecting the fish oil from degradation – but customers often also include vitamin D and vitamin K.”

However, more complex compositions, containing water insoluble vitamins and minerals are more difficult to develop and manufacture while keeping the risk of oxidation low, he further explains. For instance, adding vitamin C and iron will usually lead to increased oxidation. 

“It’s in these types of products that customers will need to rely upon the experience of the manufacturing team or contract partners, especially with softgel formulations where an optimal balance of stability and shelf life can be difficult to achieve,” says Stasko. 

Formulating for the future 
Chewable softgels, usually targeted at children, are now produced in large quantities by companies like Sirio in Europe. This makes them more attractive and palatable since the fish oils are encapsulated along with some appetizing aromas and sweetening agents.

Another development is the increasing demand for enteric capsules for fish oils with gastro-resistant shells. This means that they can pass through the stomach completely and are only digested in the intestine.  

The big advantage here is that there is no after-taste, as the fill ingredients are protected from the gastric environment. 

Furthermore, when taking supplements that have a high-fat content, like omega 3 or other oils, some users can experience acid reflux symptoms, like belching and heartburn. As a shell does not dissolve in the stomach, it avoids such symptoms altogether, giving a much-improved consumer experience. 

“What you will see in future is manufacturers like us pushing for products with a much more enhanced consumer experience – consumers don’t just want to be healthy, they want to enjoy the experience of the product as well,” concludes Stasko. 

Edited

By Louis Gore-Langton