Konjac glucomannan/xanthan synergistic interaction gel: Effect of the fine structure of xanthan on enthalpy driven assembly behavior and gel strength

Abstract

Understanding the intricate relationships between the fine structure of xanthan on the assembly of konjac glucomannan (KGM) and xanthan is crucial for developing KGM/xanthan synergistic interaction gels. A combination of micro-differential scanning calorimetry, rheometry and atomic force microscopy were employed to explore the assembly process of KGM and xanthan with varying fine structures. Xanthan possessing standard acetyl (4.57%) and high pyruvate group contents (6.49%)(SA/HP) exhibited type-A and type-B bindings when interacting with KGM through cooling process. Decreasing these group contents effectively reduced type-B binding. Additionally, removal of pyruvate groups to 5.53% amplified type-A binding and gel strength from 258 Pa to 653 Pa, thanks to the improved helical structure forming ability of xanthan. Decreasing acetyl groups also intensified type-A interaction and gel strength from 258 Pa to 872 Pa. This stemmed from the formation of more stable assembly structure of xanthan and KGM, compared to the helical structure of deacetylated xanthan. These findings hold promise for the rational design of KGM/xanthan systems for versatile applications.