MATHEMATIC MODELING OF THE RHEOLOGICAL BEHAVIOR OF THE PASTE OF XIXONA-TURRON DURING THE COOKING PROCESS

A kinetic study of the change in viscosity of Xixona Turron during the manufacturing process has been carried out. An oscillatory test has b een used with programmed heating rates of 2, 5 and 10 degrees C min(-1 ), amplitudes of oscillation between 0.01 and 0.05 cm and frequencies between 0.2 and 1 s(-1). Important changes in the structures of the pa ste are observed during the cooking process of the paste of 'Xixona Tu rron'. Initially the paste is a suspension of solid caramel and almond flour in a continuous oil phase. When the paste is heated the caramel melts and disperses into the paste which undergoes a restructuration (phase inversion). All these processes cause important changes in the viscosity of the paste which can be used to monitor the evolution of t he overall process. A mathematical modell that predicts the evolution of the viscosity with time-temperature is proposed. (C) 1998 Elsevier Science Limited. All rights reserved.