Addressing analytical requirements to support health claims on "olive oil polyphenols" (EC Regulation 432/2012)

A health claim on "olive oil polyphenols", namely, hydroxytyrosol and its derivatives, was recently approved by EC Regulation 432/2012. As no official method exists so far for the complete separation of all forms of hydroxytyrosol and tyrosol present in the oil, it is of utmost importance to find a simple, reproducible, and undisputable protocol to protect consumers and avoid unfair competition. In this study two hydrolysis protocols for the complex forms either in the polar fraction of the oil (protocol 1) or directly in the oil (protocol 2) were comparatively applied to a series of extra virgin olive oils. Protocol 1 gave at least 50% higher levels of total hydroxytyrosol and tyrosol. Nevertheless, the minimum amount of 5 mg/20 g oil of phenols was fulfilled only when suitable correction factors were introduced in the calculations to account for the differences in the mass between simple and complex phenols. Changes in the terminology used in the health claim are also proposed.