EFFECT OF THERMAL TREATMENT ON THE RHEOLOGICAL BEHAVIOR OF HABANERO CHILI (Capsicum chinense) SAUCES ADDED WITH GUAR AND XANTHAN GUMS

In foods with disperse multicomponents, such as sauces, the physical stability of the system is a parameter of the final quality. The rheological behavior of this type of product depends on intrinsic factors, such as size of the particle, molecular weight and molecular interactions, and extrinsic factors, such as temperature, pH and ionic force. In this study, habanero chili (Capsicum chinense) sauces were prepared with commercial chili pastes and water; guar or xanthan gums were added, in 0.2, 0.5 and 0.7 %, as thickening hydrocolloids. The effect of the thermal treatment was evaluated in the rheological behavior (flow and viscoelasticity) with a mixed factorial design, with three factors, in different levels. The thermal treatment affected the molecular interaction of the guar gum with water, decreased the values of viscosity, critical deformation and elastic modulus (G'), and increased those of the viscous modulus (G ''). The inverse effect was observed with xanthan gum, which conserved a more stable and better structured matrix. Xanthan gum in 0.5 % concentrations conserved the rheological (thickening) properties, after having been heated up to high temperatures; therefore, it can be used in the elaboration of habanero chili sauces with thermal treatment.