Polyphenolic composition of some Italian hazelnut (Corylus avellana L.) cultivars for a kernel quality evaluation

Hazelnut is one of the most important raw materials for the pastry and chocolate industry and they have an important role in human nutrition and health due to their very special nutritional value. Hazelnuts are a good source of monounsaturated and polyunsaturated fatty acids, proteins, vitamins, minerals and antioxidant phytochemicals. The environmental stresses such as pest attack and water stress during fruit growth and ripening are the cause of changes on biosynthetic system of the plants that can reflects in an alteration of the metabolic pool. The metabolomics method records the metabolic “fingerprints” and then attempts to associate with determinate biological functions. In fact, the metabolomics is considered an efficient tool for addressing future needs in agriculture, human nutrition and in food science, as a tool for quality, processing and safety of raw materials and final products. The untargeted metabolomics focuses on the detection of many groups of metabolites as possible to obtain patterns or fingerprints without necessarily identifying nor quantifying a specific compound(s) and untargeted analyses have been used in the identification of possible fingerprints of biological phenomena such as plant diseases. In the present research we applied untargeted metabolomic analyses in order to develop an alternative rapid diagnostic method able to detect fruit damages, that can affect kernel quality negatively. The determination of some groups of antioxidants compounds was carried out in roasted healthy and bug-damaged hazelnut samples. The samples showed a different distribution of phenolic acids and different levels were associated to nut quality and to the damage intensity.