Elevated-temperature analytical ultracentrifugation of a low-methoxy polyuronide

Abstract

Relatively little has been published on the ultracentrifuge behaviour of macromolecular solutions at elevated temperature ( > 40 °C). In this study we look at the sedimentation velocity behaviour of one particular food grade polyuronide —pectin — from 20 °C to 60 °C in a specially adapted Model E ultracentrifuge. Reduced specific viscosity measurements were also determined over the same temperature range. A small decrease in the reduced viscosity, together with a similar increase in s _20,w, suggests that the pectin chain is more flexible at elevated temperatures, but that the overall molecular integrity remains intact.