FRUIT QUALITY AND NUTRACEUTICAL COMPOSITION IN CITRUS SINENSIS (L.) OSBECK FROM NORTHERN ITALY (PIEDMONT)

In the Lake Verbano area (46°1’26.04” N; 8°41’13.92” E), thanks to a favourable microclimate, citrus trees have grown since the XVII Century. The culture was introduced into the area from Tuscany and Ligury: many old citrus trees, propagated by grafting and air layers during the last hundred years, are still growing.
Citrus sinensis (L.) Osbeck qualitative and nutraceutical fruitd traits were investigated: oranges from 15 accessions (3 accessions from Blood group, 4 accessions from Navel group and 8 accessions from Common group) were picked during 2008/2009 season.
The total phenolic content was determined by Folin-Ciocalteau method and the antioxidant activity by the FRAP (ferric reducing antioxidant power) methodology.
To analyse ascorbic and dehydroascorbic acid, hesperidin and narirutin contents the HPLC was used.
Total phenols ranged from 84.78 to 118.736 mg GAE/100 g, the antioxidant activity ranged from 7.290 to 12.578 mmol Fe2+/kg. Vitamin C ranged from 52.01 to 67.67 mg/100 ml, whereas hesperidin and narirutin ranged respectively from 14.93 to 26.30 mg/100 ml and from 13.92 to 31.88 mg/100 ml.
Compared to the latitude of the site, the citrus fruits from the Lake Maggiore area have reasonable qualitative characteristics and good nutritional properties.