The HPLC-DAD analysis and the individual identification and
quantification of the anthocyanins was carried out as reported by
Dae-Ok and Chang (2005) using an apparatus provided by Dionex
Corp. (Sunnyvale, CA), composed of a P680A pump coupled to a
PDA-100 diode array detector. Prior to injection, each juice sample
was filtered with a 0.45 mmPTEF filter and 50 mL of samplewas used
to inject. The column was a Nova-Pak C18 cartridge, 4 mm -
250 4.6mm - protected by a guard column packed with the same
material (Waters Corp., Milford, MA). The different anthocyanins
were identified by their UVevis spectra recorded with a diode array
detector (520 nm) and expressed as a percentage of their peak
areas in the chromatograms with respect to total anthocyanin peak
area.