Effect of heat treatment on conformational and structural properties of sugar beet pectin
Afsana M. Raka, Akihiko Takada, Khandker Saadat Hossain
Abstract
The effect of heat treatment on conformational and structural properties of sugar beet pectin (SBP) was investigated using Ubbelohde capillary viscometry and Fourier Transform Infrared (FT-IR) spectroscopy. Intrinsic viscosity, [η], was estimated from the Rao plot for the Fedors-Rao equation, indicating degradation of SBP by heat treatment. The temperature T dependence of [η] for both SBPs in an aqueous solution was studied from T = 30–60°C. The value of [η] was found to decrease with increasing temperature for all samples. This result indicated that the hydrodynamic volume of SBP becomes smaller with increasing T, which could be attributed to an increase in hydrophobic interaction and decreased softening of chain stiffness with increasing temperature. Compositional change due to heat treatment was investigated using FT-IR over the region 4000–400 cm−1, suggesting degradation behavior due to the heat treatment of SBP, which was in agreement with the capillary viscometry results.