RHEOLOGICAL PROPERTIES OF POTATO STARCH PASTES WITH THE ADDITION OF KAOLIN
 
More details
Hide details
 
Pol. J. Food Nutr. Sci. 2007;57(Special issue 4A):113–117
KEYWORDS
ABSTRACT
A study was undertaken to investigate rheological properties of pastes (20 g/L of starch) supplemented with kaolin at doses of 20 g/L, 40 g/L and 60 g/L, stored for various periods of time. Flow curves were plotted at a time span of 200 s, a shear rate of 0-100 s-1 and a temperature of 20ºC. The flow curves were described by means of Ostwald de Waele’s and Casson’s models. It was demonstrated that starch pastes with different addition of kaolin stored for various periods of time displayed characteristics of non-Newtonian, pseudoplastic shear-thinned fluids and that their rheological properties depended on both kaolin addition and time of storage. The pastes prepared with the addition of kaolin were characterised by higher viscosity, higher values of shearing stresses, coefficient of consistency K, plastic viscosity ηC and yield point τoC as compared to those prepared only from starch. Values of those parameters were observed to increase along with storage time in samples with the addition of kaolin, and to decrease in the case of pastes prepared only from starch.
ISSN:1230-0322