Phenolic profiling for geographical and varietal authentication of extra virgin olive oil

Background: Food adulteration represents a concern today with several notable instances involving the agri-food industry. Extra virgin olive oil (EVOO) is the main fat of the Mediterranean diet due to its high nutritional, sensory and bioactive value. At the same time, it is also one of the main agri-food commodities subjected to adulteration and frauds. Scope and approach: In this review, the potential role of phenolic compounds as candidate tools in the authentication of cultivar and geographical EVOO origin has been critically summarized, considering literature findings of the last five years (2018-2023). The main extraction methods to isolate phenols and the application of liquid chromatography are discussed along with the major advantages and limits. Emphasis was also placed on the processing of analytical data using chemometrics. Key findings and conclusions: Phenols showed a promising role in EVOO authentication since the phenolic profiling is strongly related to cultivars and geographical origin. However, the phenol fraction is also influenced by other factors, including the oil extraction technique. In conclusion, it can be affirmed that in most cases phenols were key only if used in association with other chemical markers/parameters. Future research endeavors should prioritize: larger sampling; validated and standardized analytical procedures; appropriate chemometric approach. The development of harmonized procedures would allow the creation of wide databases useful for guaranteeing the quality of EVOO.