Contaminants in the Production of Vegetable Oils–we care!

An interview with Dipl.- ecotrophologist Nadja Liebmann, freelance consultant and expert for vegetable oil quality and safety in Hamburg, chairwoman of the expert group 'Native Oils and Olive Oil' of the “Deutschen Gesellschaft für Fettwissenschaft“ (DGF) and Martin Geiger, Dipl. Food technologist, employee oil manufacture of Naturamus GmbH, member of the expert group "Products and Product Safety" of the “Deutschen Gesellschaft für Fettwissenschaft“ (DGF).
Naturamus GmbH

Mr. Geiger, Mrs. Liebmann, why are we talking about contaminants in the production of vegetable oils today? 

Martin G.: A large number of contaminants accumulate in vegetable oils because, due to the plant physiology, they accumulate in the fatty tissue of the plant over the vegetation period. Plant oils are - if one wants to speak metaphorically - so to speak the long-term memory of the contamination situation, because the oil plants accumulate their fatty tissue and therefore do not metabolize it. This means that environmental contaminants, which are fat-soluble, accumulate over the vegetation period and thus only become analytically visible. 

Nadja L.: On the other hand, this means that the contaminants are actually present ubiquitously, just below the analytical detection limit. And because the oils are separated from the rest of the plant during production, these fractions can become particularly visible, respective a concentration of the contaminant in the extracted oil. 

Which contaminants are the most problematic at the moment?

Nadja L.: Today I would like to set a focus on plasticizers and mineral oils (Germany, Europe), but globally there is a large variety and quantity of contaminants in our environment. Due to the similarity of the dissolving behavior, mineral oils are very difficult to differentiate from the vegetable oils and thus to make them analytically accessible. And due to the physiology of oil plants, we are dealing with a long accumulation cycle, so that just such actually very highly diluted outputs accumulate in the oil-containing plant tissue over the vegetation period. Another problematic example of this mechanism are plasticizers. And because these substances accumulate in the fatty tissue of the plants, surprisingly high amounts are found again in the oil produced from them. 

Martin G.: The problem now is that the accuracy of analytical methods is sufficient for analysis in the finished product oil, but not for analysis in the raw materials. And it is certainly not sufficient to be able to identify the sources of these environmental pollutants in the raw material. We have found in our operating practice: We can certainly find such environmental contaminants - despite careful raw material control - even in the oils we produce. However, we have always been able to determine during traceability that the raw materials were already the problem, not our production and the contact materials used in the process, such as seals, etc....In many cases, legal regulations only apply to what we consider to be end products: The content of polyaromatic hydrocarbons is regulated by law for oils. But often not for the raw materials. A sunflower oil with too high PAH content is not marketable, but if I use the contaminated sunflower seeds as a baking ingredient, there are no legal restrictions... 

Is this situation related to Germany or Europe-wide?

Martin G.: Some contaminants – e.g. PAH, mycotoxins –  are regulated EU-wide in legislation (EC) no. 1881/2006. But in many cases, new topics are still far from being regulated: mineral oils, plasticizers.

Nadja L.: In Germany we have a very critical reporting of the media, especially regarding mineral oils and plasticizers. That is why producers and retail are very sensibilized setting stronger specifications with (lower) limits than the European regulations. Unfortunately, out of Europe we have nothing comparable.

What is your assessment: Is the other part of society - the consumers - aware of the issue?

Nadja L.: Awareness is growing. If we want to have a sustainability discussion honestly and practice it socially, the issue of contamination of the environment - and traces of it in our food - cannot be neglected. It is very helpful that we can find a lot of these issues in the media and additional product tests by strong consumer magazines.

Martin G.: If we consider and treat sustainability according to its definition, certain plasticizers with hormone-like effects, for example, should not be released into the environment at all. And yet these substances are processed thousands of tons at a time and end up in the environment out of carelessness and convenience. From time to time, individual groups of substances come to our attention. But these are perhaps only iceberg peaks. It remains to be feared that we have a ubiquitous problem below the analytical detection limit.

Where exactly are the quality effects of contaminants on vegetable oils?

Martin G.: Food has to be safe. So, contaminants are hard to accept if we don't know what might happen to us with them, even in the long run. Safety of the oil is the biggest component of quality.

Nadja L.: Plasticizers have hormonal effects, PAHs (formed in incomplete combustion processes or drying processes)and 3-MCPDs (formed during the refining process) have proven carcinogenic effects and trans fatty acids are influencing special lipoproteins with promotion of arteriosclerosis. Aflatoxins and mycotoxins in general (can arise from inadequate seed preparation and poor storage management) have a negative impact on the health of the liver.

Is the vegetable oils industry particularly affected? What makes vegetable oils stand out in terms of the risk of contamination?

Martin G.: Oilseeds potentially accumulate contaminants over their entire growing season. This growing season is, of course, much longer with annual plants. But sunflowers, rapeseed and soybeans can also accumulate these substances. This is because the most contaminants are fat-soluble, accumulate there particularly well and are then present and detectable. Certain contaminants only become visible in this way. Other contaminants are not visible because the detection limits are not high enough. A seed may contain just as many mineral oils, but they are not so easily detectable compared to rapeseed oil.  

What are the consequences for cold-pressed or native products?

Nadja L.: Cold-pressed or native oils are not extensively processed. By law, they are only processed by pressing without any further pre- and post-treatment. Everything that is in the raw material remains in it. Contaminants may still be removed during refining. 

Martin G.: Particularly valuable oils, such as virgin and cold-pressed oils, are only produced from selected and healthy seeds, but unfortunately may still contain these contaminants. Small production quantities have to be analyzed to exclude the variety of potential substances. In doing so, one can expect high analysis costs. For a large-scale technique, this amount can be spread over batch sizes of several million liters. We, producers of smaller native batches, have to weigh the costs much more. We lack the analytical and technical capabilities to perform monitoring prior to production. Analytical safety is not primary, however. The economics beforehand are relevant. 

Then where would we actually have to go to actually counteract this problem? 

Martin G.: The direction of action should be to first create clarity: Where are the substances everywhere that, on closer inspection, are unnecessary? This could be coatings on cash register receipts or consumer goods such as hoses. It is very difficult to find out what materials are made of.  So, we need to know what all the materials we deal with in everyday life are actually made of, how they affect our immediate environment, what are the effects and are there alternatives, how much do they cost? 

We don't know a lot of things because no one has ever been interested in them. Research is a purpose-optimized tool, so we do research where there is money. People may care if there are contaminants in the oil, but no one cares where it comes from. Microanalysis / nanoanalysis is needed to provide more clarity.  

What makes Naturamus different compared to the Business standard in Germany/Europe? 

Martin G.: We try to solve the problem already in the origin together with the partners. That would be in the relation of the raw materials but also the representation of our view to the customers to work on it in the long term. Therefore, we have a conscious approach to the contaminants. Holistically! 

We should represent what is important to us and dear customer, what is important to you? We can try to implement as a service provider what is important to the customer. We are part of the value chain and responsible for implementing what is considered important.

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