Physicochemical properties of citrus pectin-kappa carrageenan mixtures

Abstract

Pectin and carrageenan are commonly used in the food industry as gelling agents, texturizers, and stabilizers. The texture and functional properties of these polysaccharides are fine-tuned by varying cation types, polysaccharide concentrations, and blending them with other polysaccharides. This study focuses on the physicochemical properties, particularly increased viscosity and microstructure of citrus pectin (CP) and kappa-carrageenan (KC). Rheological measurements were performed to examine the macroscopic properties of the mixtures. Differential scanning calorimetry (DSC) measurements were carried out to measure hydrogen bonding formation. Furthermore, fluorescence particle tracking was achieved to provide insights into the local gel structures on a microscopic scale. Adding KC to CP greatly improved its gelling capability without the need for addition of soluble solids. Microscopic analysis using particle tracking method further confirmed the results obtained from the rheological and DSC measurements.