Physics, chemical and rheological variables of the integral mango cv. Haden pulp.
Silva Filho E. D. da, Figueirêdo R. M. F. de, Queiroz A. J. de M., Brasileiro J. L. O.
Author Affiliation: Universidade Federal de Campina Grande, UFCG, R. Aprígio Veloso, 882 - Bairro Universitário, Campina Grande - PB, 58429-900, Brazil.
Engenharia na Agricultura 23 : 397-405
Abstract : This study aimed to determine physical, chemical and rheological variables of the integral pulp of mango cv. Haden. Mangos of the Haden variety from Petrolina - PE were pulped and then proceeded to physical and chemical analysis of total solids; total sugars, reducing and non-reducing; ashes; water insoluble solids; crude fiber and pectin, and rheological analysis of apparent viscosity at different speeds of rotation for the calculation of shear stresses and strain rates. In general, the physical and chemical parameters measured showed up in desired patterns for the manufacture of agro-industrial products and according to the Brazilian legislation fruit pulp. The pulp Haden sleeve showed high levels of total sugars and presented typical rheological behavior of non-Newtonian and pseudoplastic fluids, i.e., decrease in apparent viscosity with an increase in the viscometer speed. It was observed, in percentage terms, that a decrease in apparent viscosity provided by the viscometer increase in rotation speed of 0.5 to 5.0 rpm was approximately 82.70%; the rate of 0.5 to 120 rpm there was a decrease of around 98.15%. Then, models were adjusted to the rheological Power Law, Herschel-Bulkley and Mizrahi-Berk were fitted to the experimental data shear stress curve as a function of strain rate, obtaining coefficients of determination (R2) greater than 0.99 and average percentage deviations (P) lower than 3.6% in any of the models. Although, there is the possibility of using any of these to represent the rheological behavior of the Haden mango pulp, it is recommended to use the Mizrahi-Berk model to be the one with the lowest P and the highest R2.