Scientists from Spain’s Universidad de Córdoba (UCO) have developed two new methods to categorize olive oil in a more faster and reliable manner.
Classifying olive oils into the categories of extra virgin (EVOO), virgin (VOO) and lampante (LOO) can be quite a challenge. The official method includes physical-chemical and sensory analyses by means of a panel of tasters.
These tasters need to be specialized, and on many occasions they are not available. The aforementioned process also happens to be expensive and slow.
All of this has created the necessity to develop new analytical methods using affordable, reliable tools that are transferable to the industry.
Now a research group (AGR-287) led by Professor Lourdes Arce has suggested using Gas Chromatography along with Ion Mobility Spectrometry (GC-IMS) to analyze two samples an hour.
When a representative number of samples has been analyzed, the chemical information gathered is dealt with using statistical tools in order to create calibration equations.
This will allow for classification of samples of unknown oil into their respective categories in the near future.
Arce’s research further shows that, in order to obtain good results, it is not only necessary to analyze a representative number of samples but to also have samples of olive oil belonging to each of the three categories, from different varietals, from different seasons, and tasted by at least two panels whose results coincide.
Hence, these methods do not seek to substitute, but rather complement and support, the role of accredited tasting panels.
The scientists have also begun developing a new instrument to classify oils based on the use of IMS technology.
Another research project carried out by UCO doctoral student Natividad Jurado, has revealed that the proper classification of oils requires taking the chemical compounds that each taster discerns into consideration as well.
The proposed methodology is based on the extraction of certain compounds present in oil, for instance polyphenols, and then determining them using capillary electrophoresis (CE-UV) – a technique to separate different molecules – coupled with an ultraviolet detector.
Combining both CE-UV and GC-IMS should allow better detection of the oil’s non-volatile compounds by the mouth, and volatile compounds detected by the nose.
Image and content: Universidad de Córdoba (UCO)