Phytochemical profile of the ‘Mela Rosa dei Monti Sibillini’

Introduction: The ‘Mela Rosa dei Monti Sibillini’ is an old cultivar of apple cultivated in the Sibillini Mountains, central Italy, between 400 and 900 m of altitude. No scientific investigations were made on its phytonutrients so far. Therefore, the aim of this study was to investigate the phytochemical profile of this fruit, in terms of macro- and micro-nutrients, phenolic profile and aroma components. Methods: The chemical analyses were performed on samples differing in graft, soil and altitude. Macro-nutrients were determined following the AOAC standard procedure. The analysis of the minerals was made by ICP-MS [1] after a microwave-assisted acid digestion of the dry samples. The volatile compounds were studied by SPME-GC/MS analysis [2], while the phenolic compounds were investigated by HPLC-DAD-MS [3,4]. Results: The whole apple contains in average 83% of water, 11.44 % of carbohydrates, 0.32 % of fats, 1% of nitrogenous substances and 2.2% of fibre. Fructose is the major sugar contained in the fruit with a percentage of 6.48% followed by glucose (2.76%), sucrose (2.2%) and sorbitol (0.76%). The analysis of the minerals showed that K is the most abundant element (6.67 g/kg) followed by P (0.48 g/kg). The HPLC-DAD-MS analysis showed that the peel is rich of procyanidins, notably procyanidin B2, whereas chlorogenic acid was the major phenolic compound in the pulp. The aroma of the apple samples was given by more than 130 volatile compounds for the peel and more than 60 compounds for the pulp, with (E,E)--farnesene as the most representative. Conclusions: The results of this study shed light on the quality of phytonutrients contained in the Mela Rosa dei Monti Sibillini and their possible health effects. They also represent the scientific basis for the improvement of its cultivation at the regional level.