2.7. Soluble tannins determination
Soluble tannins were measured according to Taira (1996). Fivegrams of fruit tissue (including skin and flesh) was homogenizedwith 25 ml of 80% methanol in a blender and then centrifuged. Thesupernatant was collected and the precipitant was re-extractedwith 80% methanol and centrifuged. The combined supernatantwas brought to 100 ml with distilled water. One ml of sample solu-tion was mixed with 6 ml distilled water and 0.5 ml Folin–Ciocalteureagent (previously diluted 10-fold with distilled water). After3 min, 1 ml of saturated sodium carbonate and 1.5 ml of distilledwater was added and kept for 1 h at ambient temperature beforemeasuring absorbance at 750 nm using a UV-Vis Spectrophotome-ter. The blank contains only water and the reagents. Soluble tanninswere quantified from a calibration curve obtained by measuring theabsorbance of known concentrations of gallic acid.