Optimization of the Official COI Method for Faster Analysis

Biophenols in olive oil are natural chemical compounds with antioxidant properties that offer numerous health benefits. These compounds include simple phenols, such as tyrosol and hydroxytyrosol, and complex phenolic compounds such as oleuropein and ligustroside.

An important indicator of oil quality and its health benefits is the concentration of these compounds in olive oil. Their concentration can be mainly influenced by:

·       The quality of the extraction process;

·       The variety of olives used;

·       The degree of ripeness of the olives;

·       The storage method and freshness of the product.

In Italy, the minimum concentration of biophenols in extra virgin olive oils is regulated in most territorial production specifications to guarantee maximum product quality. Internationally, the official method for determining the concentration of these compounds in olive oil is the COI/T.20/Doc no. 29/rev 2 2022 method. This method involves very long analyses, taking about 85 minutes for each sample, in addition to the preparation phase, and is carried out using the HPLC-DAD instrument (high-pressure liquid chromatography with diode array detector).

The Centro Analisi CAIM laboratory, accredited for this determination with the official COI method, aimed to improve customer service in terms of quality and speed of analysis. They have optimized the method by enhancing instrumental efficiency using a system that can work at higher pressures (UPLC, ultra-pressure liquid chromatography) and by employing a dedicated chromatographic column with improved performance characteristics.

Through this new configuration, the laboratory has managed to decrease the analysis time from 85 minutes to 25 minutes per sample while maintaining compliance with the official method and ensuring the required quality standards through participation in national and international proficiency tests.