Effect of hydroxypropyl cross-linking modified tapioca starch on retrogradation characteristic of rice starch

The hydroxypropyl cross- linking modified tapioca starch ( HP- CLTS) was added to the rice starch.HP-CLTS on characteristics of rice starch were studied by pasting properties, water- holding capacity, texture, microscopic structure analysis and FT-IR analysis.The RVA curves showed pasting temperature and setback was decreased, while peak viscosity, hot paste viscosity, cold paste viscosity and breakdown were increased.Furthermore, the water-holding capacity increased and hardness of rice starch decreased with addition content.The rice starch with addition of HP- CLTS retrograded for 7 days at 4℃ after freeze- drying showed honeycomb texture, and there were holes pass through the inner. It was demonstrated from microscopic structure that HP-CLTS inhibited that water loss from the gel.The results implied that HP-CLTS increased starch water holding capacity, played an important role in improving rice products aging resistance.FT-IR found that the rice starch with addition of HP- CLTS had more pronounced band at 1022cm- 1, and the band at 1047cm- 1tends to less predominant.