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Rheological Properties of Some Hydrocolloid Mixtures at Low Temperatures

D. Šubarić1, Vlasta Piližota1 and T. Lovrić2


1
Faculty of Food Technology, Vijenac I. Meštovića 7, 54 000 Osijek, Croatia
2Faculty of Food Technology and Biotechnology, Pierottijeva 6, 41 000 Zagreb, Croatia

Article history:

Received June 15, 1994
Accepted September 26, 1994

Summary:

This paper deals with the rheological properties of some hydrocolloid solutions and their mixtures at low temperatures (between +5 "C and -5 °C). The aim was to determine the influence of temperature on the rheological properties of hydrocolloids and the existence of interaction among hydrocolloids examined. The rheological properties (shear stress and apparent viscosity) were measured by rotational viscosimeter with the shear rate ranging from 81 to 1312 s-1 and the temperature range between +5 and -5 °C. The results showed that temperature reduction had significant influence on the rheological properties of solutions of hydrocolloids as well as their mixtures. This phenomenon is especially evident with mixtures of hydrocolloids (galactomannan hydrocolloids and carragecnan) between which exists an interaction particularly at low temperatures (0 "C and lower).