Effects of acid hydrolysis intensity on the properties of starch/xanthan mixtures

The effects of acid hydrolysis intensity on the physicochemical properties of starch/xanthan gum (XG) system were studied. Waxy corn starch (WCS) was subjected to different concentrations of hydrochloric acid, and crystallization and relative molecular weight analysis were performed. The results revealed that the starch granules became smaller during acid hydrolysis. X-ray diffraction pattern analysis showed that the crystal structure did not change with acid hydrolysis. Evaluation of the properties and digestibility of different acid-thinned starch/XG systems indicated that the viscosity of acid-thinned starch/XG decreased with increased acid hydrolysis intensity. Rheological property measurements indicated that the compound systems were a pseudo-plastic fluid, which is a typical weak gel structure. Finally, we show that the WCS1.0 M/XG has the highest stability of the tested mixtures. We conclude that adjusting the conditions of acid hydrolysis improves the stability and food quality-enhancing properties of starch.