4种抗性淀粉的主要理化特性

Main Physicochemical Properties of 4 Resistant Starches

采用二次循环压热法制备、纯化得到了绿豆、马铃薯、锥栗和板栗抗性淀粉,并对其主要理化性质进行了研究。结果表明:与相应的原淀粉相比,4种抗性淀粉的平均聚合度显著降低,其微观结构为不规则的片层状堆积结构;绿豆、马铃薯抗性淀粉晶体为B型,结晶度升高,且B型晶体所占比例显著增加;锥栗、板栗抗性淀粉晶体为V型,且V型晶体显著增加;4种抗性淀粉的溶解度显著降低,且对α-淀粉酶具有较强的抗性;4种抗性淀粉的糊化焓△H值差别不大,但绿豆与马铃著抗性淀粉的起始糊化温度T_0、峰值糊化温度T_P、终止糊化温度T_C值均要高于锥栗和板栗抗性淀粉的T_0、T_P、T_C值,特别是绿豆与马铃薯抗性淀粉的T_0、T_P、T_C、△H值显著增高。

The resistant starches of mung bean, potato, Castanea henryi and C. mollissima have been produced and purified by the secondary loop autoclaving method. Their main physicochemical properties have been studied in the paper. The results demonstrated that compared with their native starches, the objects＇ average degrees of polymerizations obviously decreased and the microstructures all changed to irregular lamellar stacking structure. The crystal type of mung bean or potato resistant starch was B type, and the objects＇ crystalline degrees increased, which the proportions of type B crystals increased significantly. However, the crystal types of C. henryi and C. mollissima resistant starches were V type and the proportion of type V crystals singificantly increased. In comparison with objects＇ native starches, the solubilities obviously decreased and had a stronger resistance with α - amylase. The differences of the gelatinization enthalpies （ △H values） were very small, while onset （TO ）, peak （ TP ） and conclusion （TC ） gelatinization temperatures of mung bean and potato resistant starches were higher than those of C. henryi and C. mollissima resistant starches. To, Tp, To and △H values of mung bean and potato resistant starches increased notably.