Differentiation of raspberry varieties according to anthocyanin composition

Four Spanish raspberry (Rubus idaeus L.) cultivars, Autumn Bliss, Heritage, Rubi, and Ceva, were studied in order to determine, qualitatively and quantitatively, both anthocyanins and vitamin C composition, owing to their significance as dietary compounds with antioxidant activity and also to the relation with color quality. Raspberry anthocyanin composition, determined by HPLC and GC-MS, was characteristic to each cultivar. The higher anthocyanin content expressed as cyanidin-3-glucoside was found in the late cultivars, Rubi (96.08 mg/100 g f.w.) and Ceva (122.88 mg/100 g f.w.). Three cultivars showed cyanidin-3-sophoroside (63.86–21.91 mg/100 g f.w.) and cyanidin-3-glucoside (25.12–14.00 mg/100 g f.w.) as the major pigments, while Autumn Bliss had a similar relative amount of cyanidin derivatives, cyanidin-3-rutinoside being the pigment in major concentration (10.53 mg/100 g f.w.). The vitamin C contents were determined by HPLC. The Rubi cultivar showed the highest amount of vitamin C (31.14 mg/100 g f.w.). The organic acids were determined by HPLC as fruit constituents related to color quality. Citric acid was the main non-volatile organic acid (90%) in all raspberry cultivars and the Rubi cultivar showed the highest total non-volatile organic acids content (2003 mg/100 g f.w.). Hunter color CIE values were also determined, showing that Rubi was the reddest raspberry cultivar.