Effect of temperature and concentration on Rheologioal properties of "Kesar" mango juice

Flow characteristics of juice of "Kesar" mango have been investigated and rheological parameters were evaluated using rotational viscometer at temperature 20, 30, 40, 50, 60 and 70 degrees C at concentration of 7.6%, 11.69%, 16.37% and 26% total solid. The experimental results followed the power law model for the best fit and the values of flow behaviour index (n) was less than unity (0.20-0.33) at all temperature and concentration revealing the shear-thinning (pseudoplasticity) nature of juice. An obvious correlation between consistency coefficient, in the range of 0.32-80.09 Pa s(n) and inverse absolute temperature has been exhibited by Arrhenius model. Power equation indicated that consistency coefficient increased non-linearly with increase in concentration. The magnitude of activation energy were found in the range of 3.8-13.7 kJ/mol K. (c) 2006 Elsevier Ltd. All rights reserved.