Contents of main phenolics and antioxidative capacity in frozen raspberry fruits (Rubus idaeus L.) from Arilje growing area.

Abstract

Individually quick frozen (IQF) fruits of the most abundant raspberry cultivars (Meeker and Willamette) in Western Serbia were randomly taken from the commercial cold storage in Arilje growing area, and analyzed for main phenolics and antioxidative capacity. All samples for freezing were harvested in the full ripening stage in the orchards in close proximity to the commercial cold storage, frozen by conventional freezing, and stored at -18°C, prior to use. Using high-performance liquid chromatography, high content of ellagic acid (from 13,99 to 27,01 mg/100 g fw for Meeker; from 26,15 to 35,22 mg/100 g fw for Willamette) and cyanidin (from 20,75 to 29,97 mg/100 g fw for Meeker; from 32,97 to 64,68 mg/100 g fw for Willamette) were determined. Significant amounts of pelargonidin (up to 7,08 mg/100 g fw), gallic acid (up to 4,42 mg/100 g fw), quercetin (up to 1,56 mg/100 g fw), and apigenin (up to 0,42 mg/100 g fw) were also detected in all samples. Although the raspberries cv. Willamette contain higher concentration of detected phenolics than raspberries cv. Meeker, nevertheless antioxidative capacity is nearly equal for both cultivars examined.