An Airport Explosives Test Could Catch Olive Oil Fraud
An airport explosives test, the technique used to sniff out explosives and drugs in luggage, could become a quick screen for olive oil fraud, according to chemists at the University of Córdoba. Their method sorts extra virgin from lower grades in about 15 minutes, and the story has been picked up again this week by the Spanish olive press. Here is how it works, how good it is, and why it would not replace the tasting panel.
What was reported
The technique is ion mobility spectrometry, the kind of machine that analyzes swabs at airport security. A team in the University of Córdoba’s analytical chemistry group, led by Professor Miguel Valcárcel with associate professor Lourdes Arce, has spent two years applying it to olive oil, as the basis of doctoral research by Rocío Garrido. The group first announced its evaluation model in early June. Olive Oil Times returned to it on August 2 and the Jaén site Esencia de Olivo on August 6, noting that some companies and cooperatives have already shown interest after the results appeared in specialist journals.
The method is simple on paper. About a gram of oil is warmed to 60 °C in a closed vial so that it gives off its volatile compounds. The instrument separates those compounds and produces a spectrum, and the pattern is used to classify the oil as extra virgin or not.
| Point | What was reported |
|---|---|
| Time per sample | About 15 minutes |
| Sample preparation | None needed |
| Reported reliability | About 90 percent |
| Intended use | Fast screening, not a final verdict |
| Other food trials by the group | Fish freshness, white wines, the diet of Iberian pigs |
Why it matters
The weak point in olive oil grading is the step that matters most. Chemical tests can catch many problems, but the final word on whether an oil is extra virgin or merely virgin belongs to a trained tasting panel, and there is no fast, cheap instrument that can confirm the panel’s verdict. The Córdoba researchers say that gap has caused real trouble for producers, who can find themselves suspected of mislabeling on the strength of a panel result alone.
A 15-minute screen would let a regulator, a bottler or a supermarket check far more oils, and send only the doubtful ones on to a full panel and laboratory analysis. The timing is pointed: Consumer Reports has just published a test of supermarket extra virgins in the United States in which most failed.
The limits
- Ninety percent is not enough for a verdict. One oil in ten misclassified is fine for screening, not for a fine or a court case. The team said in June that more work is needed before it can classify with full certainty in routine food labs.
- It needs the panel to learn from. A classification method like this is normally built on oils already graded by tasters, so it inherits their judgments rather than replacing them.
- Adoption is slow. Official testing methods change through the International Olive Council and the EU, which takes years.
Most mislabeled extra virgin is not a chemical mystery. It is tired or poorly made oil that a panel would mark down in minutes. The reason so little of it is caught is that almost nobody pays for panel tests on shelf samples. A cheap screen changes that economics, which is exactly why bottlers of ordinary oil will not be rushing to adopt it.
The U.S. results are in Consumer Reports Olive Oil Test: Only 9 of 23 Pass as Extra Virgin. What the tasters are looking for is explained in Fusty, musty, winey, rancid: the chemistry of off-flavours, and a Spanish row over mislabeled oil in El País Report on Mislabeled Extra Virgin Stirs Spain.
Sources
- Esencia de Olivo: Detectores de explosivos para evitar fraudes en el aceite (in Spanish)
- Olive Oil Times: Test to Detect Explosives Also Finds Bad Olive Oil
- Olive Oil Times (Mercacei): Researchers Find New Technique to Prevent Olive Oil Fraud