DINIZ, E.; http://lattes.cnpq.br/8461167201486842; DINIZ, Edênia.
Abstract:
The water activity and the electrical conductivity of the West Indian cherry, umbu-cajá, sapodilla fruit and melon pulps, characterized as the moisture content / total solids, at concentrations that varied from 7° to 27°Brix, were evaluated. The water activity was evaluated in temperatures of 20°, 25°, 30° and 35°C, in hygrometer DECAGON CX - 2. Electrical conductivities of pulps were measured in conductivity
meter HANNA Instruments HI 9032. The readings were made at 25°, 30°, 35°, 40°, 50° and 60°C. From the experimental data the relationship between water activities and concentration of the samples was studied, as well as the temperature effect. The obtained values for moisture, water activity and electrical conductivity were analyzed
by the ASSISTAT software, version 6.5. From the linear regressions obtained with experimental values of moisture content versus concentration, the minimum and maximum determination coefficients (R2) obtained were 0.964 and 0.995, for melon and West Indian cherry, respectively, and the minimum and maximum mean relative deviation modulus (P) were, 0.33% and 1.11%, for West Indian cherry and melon, respectively. For all the pulps, decreases of water activity were observed with the increase of total soluble solids (°Brix). Among the temperatures, the water activity of the samples presented several tendencies with the temperature variations. The results obtained for electrical conductivity demonstrated an increase of the conductivity with
the increase of the concentrations. In respect to the influence of an increase in temperature, it was not possible to determine an increase or decrease tendency of the electrical conductivity.
