Dgu 20a3 a5

The identification and quantification of phenolic compounds in roselle wine was carried out as described in Ifie et al. (2016) . A UFLCXR system (Shimadzu) consisting of a binary pump, coupled with an online unit degasser (DGU-20A3/A5), a solvent delivery module (LC-20AD), a thermostat autosampler/injector unit (SIL-20A) and a photodiode array with multiple wavelength (SPD-20A) was used for the analysis. The mobile phase was 0.1 % (v/v) trifluoroacetic acid (mobile phase A) and trifluoroacetic acid/acetonitrile/water (50:49.9:0.1) (mobile phase B). The flow rate was set to 1 mL/min and the injection volume was 10 L.
Chromatographic separation was performed on a Gemini C18 5 m, 250 mm ×4.6 mm column (Phenomenex, Macclesfield, UK) and the oven temperature was maintained at 35 °C.
The photodiode array detector was set to measure at wavelengths of 265, 320, 360 and 520 nm. The gradient program was started at 8 % B and increased linearly until 18 % solvent B was achieved at 3.50 min, solvent B was increased to 32 % at 18 min, 60 % at 28 min, and then 100 % at 32 min. Finally, 100 % B was kept constant for 4 min, followed by 3.5 min isocratic re-equilibration for initial conditions.