The OLEUM revolution of quality and authenticity control

From sustainability to big data for compliance

By Tullia Gallina Toschi

The OLEUM project has ended with a final public conference held on February 17th and 18th and is available in videos on the project website. The objectives of the project were pragmatic. OLEUM did not want to extensively investigate the possible quality markers of olive oils regardless of the cost and actual availability of the instruments in the quality control labs. OLEUM wanted to identify new methods applicable in existing conditions or reduce time, solvents and consumables of the methods already legally recognized. The keywords were “renew” or “revise”. Today the importance of the link between the project and the fundamental elements of sustainability is evident. OLEUM's research proposal, sent to the Commission on 26 June 2014, anticipated, for example, some targets of goal 12 of the 2030 agenda, adopted by the UN in September 2015, such as the necessity to reduce release and non-recycling or waste of chemicals (target 12.4) and from this point of view the OLEUM approach can be extended to many other foods.

The other fundamental aspect of the project was the combination of prevention and control. All the stakeholders of the quality of such a precious food as extra virgin olive oil (EVOO) were placed at the same table: small or medium primary producers, who want the oil to be fairly remunerated; large producers or bottlers, who need an additional margin and who must necessarily offer to the market different qualities and prices, but who no longer want to find themselves in conditions of non-compliance and below the legal quality and public control laboratories that must and want to carry out controls with highly diagnostic, robust, rapid, effective and harmonized methods on all territories. Last but not least, the consumer, who must be informed about a product that is widely used but little known in substance, and who wants quality guarantees. Therefore, OLEUM has moved in two directions: developing rapid screening methods useful for prevention and quality control in the companies but developing in parallel and closely relating to highly sensitive and specific methods to be proposed to the standardization tables for adoption in public controls quality.

One of the problems was the sensory quality. It represents one of the three founding pillars of EVOO quality, together with the stringent elements of "freshness" (which can be defined as the quality of the oil at zero time) and the integrity of the starting olives. The technological specificity, being EVOO only pressed, centrifuged and filtered (not refined) product, is an important quality, shared with virgin oil (VOO) which does not have such rigorous determinants of the previous quality. Without flawless sensory quality, EVOO would not exist even though this element remains one of the most difficult to assess. It is well known that most of the non-conformities concern the sensory aspects. For this reason, OLEUM, taking advantage of all the literature on the matter, has developed and validated two high resolution chromatographic methods (SPME-GC/MS and SPME-GC/FID) intended for public control laboratories that will be brought to the table of the International Olive Council so that they can be adopted once limits and ranges will be established for the most relevant markers. These instrumental methods can be combined with the Panel test (sensory evaluation) in case of doubtful classifications.

In parallel, the same levers, i.e. the minimum number of volatile compounds considered highly diagnostic (15-18 compounds) were used to propose rapid screening methods capable, for example, to pre-classifying the EVOO product on the basis of sensory quality. These methods will be especially useful for bottlers to quickly decide whether or not to buy a batch of oil.

The challenge of OLEUM, which has also created an international network, which brings together stakeholders, broadens knowledge about olive oil and EVOO, promotes competitiveness on the product and control methods a positive lever. These are levers of harmonized authenticity and quality, shared robust scientific culture, which isolate only the fraudsters, do not nourish the chains of negative promotion and haters of the product, but instead are aimed at giving in practice further elements of certainty.

Finally, I do not dwell on the many directions in which the project has moved to search for new markers and new methods. I can only refer to the page of the website (http://www.oleumproject.eu/) collecting all the articles published so far and available in open access and I underline that OLEUM has also concentrated in the forward-looking direction of proposing, for the first time, the validation of a non-targeted method.

It is also essential to mention the hard research work that has also come to the implementation of reference materials (RMs): four have been produced and validated. Two sensory materials, rancid and winey-vinegary and two standards for volatile compounds to be used as instrumental calibration material. They are all ready for the market. Also in this case, the quality control of olive oil leads the way for a larger food market.

To conclude and to try to give strategic direction of the future of quality and authenticity controls for olive oil, a promising way that EU could take includes: 

1. A joint strategy, to combine sensory and instrumental data (now an easy quantification of specific volatiles is affordable!), useful in cases of disagreement between two panels;
2. An improvement of the proficiency and alignment of the panels by mutual calibration, possible in the near future, if reproducible reference materials (RMs) will be available on the market;
3. Real and virtual compliant compositions progressively implemented and stored (for the virtual) in a repository of validated data (e.g. OLEUM databank) to be used as authenticity reference;
4. OO quality and authenticity information to be put in relation with volumes produced and their geolocation. The intersection between official quality controls and traceability, typical of a blockchain scenario, could be the next fraud countermeasure.

Everything moves from a single marker of quality and authenticity to an overall vision of an oil that could be defined as "biometric". But we cannot forget to proceed with an incremental, simple and robust approach, gradually distilling elements of complexity to make a new effective synthesis, avoiding any sensationalism, which introduces uncertainty and approximation. This is the difficult challenge that OLEUM has won.