中文摘要：

为了得出菊粉在酸性条件下的成胶规律、凝胶稳定性和质构特性，考察了pH值对不同菊粉含量形成的凝胶性能的影响。试验发现，随pH值降低，菊粉成胶能力减弱，成胶时间延长，而凝胶指数随菊粉含量的增加而增大，随pH值的降低而减小；当pH值为1时，60%的菊粉溶液也不能形成凝胶。随菊粉含量的升高，其凝胶持水力增加，其增加幅度随pH值的降低而减弱，pH值分别为7、5和3时，60%的菊粉凝胶持水力较40%的凝胶分别增加了9.4%、5.75%和5.47%；菊粉含量越高，凝胶对酸的稳定性越强，当pH值为3和水解时间为24 h时，40%菊粉凝胶的水解速率分别是50%和60%的1.35倍和2.97倍。质构仪分析发现，pH值高低与菊粉凝胶的硬度、强度、黏着性、凝聚性、咀嚼性等呈正相关。差示扫描量热仪分析发现，当pH值由7下降到3时，50%菊粉凝胶的可冻结水含量增加程度最大，达到26.0%。

英文摘要：

With the aim to explore the gelling rules, the stability and the textural properties of inulin under acidic conditions, and the effect of pH value on the gelatin were studied at different concentrations of inulin. The experimental results show that the gelling ability decreases and the gelling time increases with the decrease of pH value. The volumetric gel index increases with inulin content increase and decreases with pH value decrease. When pH value decreases to 1,gelatin can’t be formed even the concentration of inulin solution is high as 60%. The water retention of gelatin increases with the increase of inulin content and the increase extent becomes weak as pH value decreases. The water retention of 60% gelatin increases by 9.4%, 5.75% and 5.47% compared with that of 40% gelatin at pH value 7, 5 and 3, respectively. The higher the inulin content is, the stabler the stability of gelatin to pH value is. The acid hydrolysis rates of 40% inulin gelatin are 1.35 and 2.97 times higher than that of 50% and 60% gelatins when the pH value equals 3 and the hydrolysis time is 24h. Texture profile analysis shows that pH value has positive correlations with the hardness, strength, adhesiveness, cohesiveness and gumminess of gelatin. Differential scanning calorimetry analysis shows that the freezable water content of 50% gelatin increases to the maximum, 26.0%, when pH value decreases from 7.0 to 3.0.