Virginity Testing - the Olive Oil Method

For consumers wanting to eat a healthy diet, this often means paying more and buying premium food products such as extra virgin olive oil (EVOO). Harvested as the first pressing from freshly picked olive fruits, EVOO is prized for its taste and beneficial levels of monounsaturated fatty acids. It is a key component of the heart-healthy Mediterranean diet and consumer demand is rising above production levels. Unfortunately, this high demand can be tempting to unscrupulous producers, who try to maximize their profits by blending EVOO with cheaper alternatives. This adulteration with lower quality ingredients can be hard for both consumers and food inspectors to detect. While adulteration often simply results in a lower quality product, using potential allergens or non-food grade materials is a serious concern. EVOO can be extended using lower quality, refined olive oils from solvent extractions of EVOO by-products e.g., pomace oil, or with cheaper vegetable oils, e.g., sunflower, soybean or canola. Usually this doesn’t pose a health risk but, since adulterants are not declared on food labels, the consequences of unintentionally consuming an allergen like peanut oil is possible and can be serious for people with dietary allergies. Moreover, the consequences of adulterating EVOO with non-food grade oils can be disastrous. These oils can look similar to olive oil but ingestion can be fatal. In one notable incident, the “toxic oil syndrome” in the early 1980s, olive oil adulteration using industrial-grade rapeseed oil caused many deaths and left others with chronic ill health. Researchers believe that the rapeseed oil, not meant for human consumption, was contaminated with aniline and other toxins as a result of industrial processing. Scientists at Thermo Scientific have recently refined a simple high-performance liquid chromatography (HPLC) and charged aerosol detection method that uses the Dionex UltiMate 3000 system to characterize the triglyceride (TAG) profile of an oil sample. Using a straightforward dilution step for preparation, the samples were quickly analyzed to show the differing TAG profiles in pure EVOO and product adulterated with corn, hazelnut or pomace oils. Principal component analysis (PCA) easily highlighted differences in the chromatograms, allowing discrimination between pure and adulterated samples according to TAG clusters. It’s also worth noting that this method isn’t just for food safety testing; HPLC and charged aerosol detection is useful for examining lipid profiles in a number of food and industrial oils. Numerous classes of lipids can be detected in one analysis after a simple dilution pretreatment. Using only a single HPLC method, complex oil samples can be fully characterized and laboratory procedures streamlined, thus saving time and resources. Interested in how Charged Aerosol Detection works? Learn more about this highly sensitive universal detector which is capable of measuring all non-volatiles and many semi-volatile analytes with similar response.