Physico-chemical and sensory properties of formulated syrup from black plum (Vitex doniana) fruit.

The fresh ripe fruit pulp and syrup, produced using the open pan evaporator, of Vitex doniana were analysed physico-chemically. Results show that the edible pulp of the ripe fruit is fairly rich in vitamin C (18.1 mg/100 ml) but acidic (pH 4.38) and poor in protein (0.82%) and oil (0.56%). The syrup yielded a DE value of 52, total dissolved solids content of 67 degrees Brix and a refractive index of 1.4762 at 20 degrees C. The syrup was moderately viscous (2.1 Poiseuille), acid (pH 4.45) but relatively poor in vitamin C (2.8 mg/100 ml) and protein (0.3%). Sensory evaluation showed no significant difference (p < or = 0.05) in taste, flavor and overall acceptability between V. doniana syrup and honey. Both physico-chemical and sensory results indicate that the syrup was highly desirable and can substitute for other syrups as a nutritive sweetener.