Rheological Properties of Frozen Concentrated Orange Juice (FCOJ) as a Function of Concentration and Subzero Temperatures

Abstract

Data on flow properties of Frozen Concentrated Orange Juice (FCOJ) produced from oranges cv. Pera-Rio (65.04 °Brix, 8.8% w/w pulp content, 2.5% w/w pectin, 3.84% citric acid, 1.293 g cm⁻³) from −18 to 0°C were fitted with appropriate predictive models. The power law model was found to be the most appropriate to fit the flow curves obtained for FCOJ between 46.56 and 65.04 °Brix. In higher concentrations, thixotropy was observed and showed more temperature dependence. A single equation combining Arrhenius and exponential relationships was applied to describe the temperature effect and shear rate on the quantity of breakdown of FCOJ.

Keywords:

• Frozen concentrated orange juice
• Rheological properties
• Thixotropic behavior
• Power law model

ACKNOWLEDGMENTS

The authors wish to thank BASCITRUS S.A. for helpful suggestions and sample material supply; João Jesuino Demilio for technical support; and to State of São Paulo Research Foundation (FAPESP) for financial support.