Influence of Olive Fruit Fly (Bactrocera oleae) Attack on the Chemical Quality and Oxidative Stability of Extra Virgin Olive Oils from Abruzzo Region (Italy) produced with Industrial Mill

Plants are subject to attacks from different organisms and as a result have evolved a complex, integrated defence system against potential pathogenic organisms to ensure survival, growth and development. It has been shown that plants respond to pathogenic attack by synthesizing compounds that activate the defence system in fruit. Additionally, there are enzymes involved in the biosynthesis of different compounds with biocide activity such as alkaloids, cianogenic glycosides, glucosinolates, terpenoids, flavonoids, saponins and phenolic acids. The biocide action of polyphenols in vitro against bacteria, yeasts and fungi has been investigated, although there are only a limited number of studies regarding the defence response of polyphenols in fruit, and in particular, the polyphenols in kiwifruit and tomato have been examined. The quality of virgin olive oil is strongly related to the health status of the fruit from which it is extracted. One of the most detrimental enemies of the quality of olive oil is the olive fruit fly (Bactrocera oleae). This insect can reduce the oil yield, affect quality parameters (acidity, peroxide value, UV absorbance, organoleptic quality) and negatively alter the chemical composition (sterols, phenols, fatty acid, volatile fraction). The severity of the negative effects depends on the stage of the development of the olive fly, the intensity of the attack and the olive variety.