湿热处理对不同晶型淀粉理化性质及消化性的影响

采用三种不同晶型淀粉即玉米淀粉(A型)、马铃薯淀粉(B型)、豌豆淀粉(C型)为原料,在水分含量为25%、温度120℃条件下湿热处理13 h,研究湿热处理对不同晶型淀粉的理化性质及消化性的影响。研究表明,与原淀粉相比,经湿热处理的三种淀粉的结晶结构均发生了改变,玉米淀粉由A型变为了A+V型,马铃薯淀粉和豌豆淀粉分别由B型和C型变为了A型;三种淀粉颗粒表面均出现了不同程度的破损;三种淀粉的部分颗粒的偏光十字的中心强度有所减弱;三种淀粉样品的糊化温度均升高,但A型和B型淀粉的焓值降低,而C型淀粉的焓值升高;三种淀粉的抗性组分含量均有所升高,抗消化性显著增强,其中C型淀粉变化最明显。

Effect of Heat-moisture Treatment on the Physicochemical Properties and Digestibility of Starches with Different Crystal Structures

In this study, three types of starch, each with a different crystal structure corn starch (A-type), potato starch (B-type) and pea starch (C-type)] were treated using heat at 120°C for 13 h in the presence of 25% moisture content. The effect of heat-moisture treatment was studied in terms of physicochemical properties and digestibility of starch. The results showed that, compared with native starch, the crystal structures of all three starches changed after heat-moisture treatment. The original A-type structure of corn starch changed to (A+V)-type, while both, B- and C-type structures present in potato and pea starches changed to A-type. The starch granules showed different degrees of damage on the surface, while some showed a decrease in the central intensity of the Maltese cross. The temperature required for gelatinization increased and the enthalpy values decreased in A- and B-type starches but increased in C-type. The content of resistant starch component was elevated and the anti-peptic activity was significantly enhanced. The changes in C-type starch were observed as most significant.