VISCOSITY MEASUREMENTS OF POTATO STARCH PASTE WITH THE RAPID-VISCO-ANALYZER

Viscosity behaviour of potato starch paste was measured with the Rapid Visco Analyzer (RVA, Newport Scientific, Warriewood, Australia). By reason of high viscosity properties of potato starch suspensions, starch concentration was reduced from 3.0 to 2.0 g starch weight (14% moisture) in 25 ml distilled water. In view of Brabender viscograms a short temperature profile (13 min including heating, stable hot phase, and cooling) achieved the best results. Reproducibility of RVA-measurements was high as well with new canisters as with re-used ones. Coefficient of variation (s%) was below 2%. A comparison of RVA and Brabender viscograms pointed out a close correlation of r = 0.94 for both, the peak viscosity and the viscosity difference between peak and trough.