Abstract

BROUSSE, María M; MARTOS, María A.  and  CRUZ, Nancy. Viscosity and density of grape juice (Isabella) for process applications. Rev. cienc. tecnol. [online]. 2010, n.13. ISSN 1851-7587.

The density and viscosity of grape juice were measured at four temperatures in the range of 303 to 333 °K and five concentrations between 2 and 12,5 °Brix. The viscosity was determined using an Ostwald type capillary viscometer. Density was determined using a pycnometer. The density and viscosity decreased when temperature increased and when concentration decreased for the temperature and concentration in the range studied. The temperature did not have significant influence (p > 0,05) on the density, however there were great differences (p < 0,05) with concentration. The viscosity was significantly influenced by temperature and concentration (p < 0,05). The density of the juice varied linearly with concentration (r2 = 0,99). The value of viscosity was correlated with temperature and concentration by usual models. The value of the activation energy ranged between 6.2 and 7.99 kJ/mol.

Keywords : Viscosity; Density; Grape juice.