甘薯交联抗性淀粉热力学性质与消化性研究

Thermodynamic properties and digestibility of sweet potato cross-linked resistant starches

根据膨胀度、糊化度及差示扫描量热仪(DSC)测得热力学参数,综合分析甘薯交联抗性淀粉和原淀粉热力学性质,并采用Jenkins提出In–vitro模型测定淀粉体外消化性。结果表明:在同一温度下,甘薯交联抗性淀粉膨胀度和糊化度均较原淀粉低,且交联剂用量越高,淀粉膨胀度和糊化度越小;DSC测试结果显示,甘薯交联抗性淀粉相转变温度To、Tp、Tc随交联剂用量增加而升高,Tc–To和△H均比原淀粉低。In–vitro消化模拟实验表明,甘薯交联抗性淀粉消化性比原淀粉低,并随交联剂含量增加,消化产物量减少,消化速度降低。

The thermodynamic properties of sweet potato cross–linked resistant starches and native starch were analysed synthetically based on swelling power,degrees of gelatinization and thermodynamic parameters measured by differential scanning calorimetry（DSC）.In–vitro model proposed by Jenkins was investigated the digestion of starch.Results showed that swelling power,degrees of gelatinization of sweet potato cross–linked resistant starches were lower than native starch at the same temperature,and the higher dosage the crosslinking agent was,the smaller swelling power and degrees of gelatinization of starch were.The phase inversion temperature To,Tpand Tcof cross– linked resistant starch rose with increasing crosslinking agent dasage.In–vitro digestion test showed that digestibility of all the cross–linked resistant starches were lower than native starch.The total carbohydrate digestion products and the average rate of digestion of resistantstarches were decreased with increasing crosslinking agent dasage.