韧化处理对板栗淀粉特性的影响

以燕山板栗淀粉为材料,在30、40和50℃分别进行韧化处理。采用扫描电子显微镜(SEM)、X-射线衍射分析(XRD)、差示扫描量热分析(DSC)及体外消化法等方法,研究了韧化处理对板栗淀粉颗粒结构、理化特性和体外消化性的影响。研究表明:与原淀粉相比,韧化处理后2种板栗淀粉的直链淀粉含量降低,淀粉颗粒破损率增大,但淀粉仍为C型晶体。随着韧化温度的升高,淀粉颗粒表面出现凹坑和损伤越显著,膨胀度随着处理温度的升高而降低。DSC分析表明,韧化处理使淀粉的糊化温度升高,热焓变化不大。不同的韧化处理温度对板栗淀粉体外消化性有不同的影响,韧化处理使淀粉的快消化淀粉(RDS)含量减少,慢消化淀粉(SDS)含量增大。

Effect of Annealing on Characteristics of Chestnut Starches

Chestnut starches were annealed at 30°C, 40°C and 50°C, respectively to study the effect of annealing on granule structure, physicochemical properties and in vitro digestibility of chestnut starches. The modified products were characterized by SEM, XRD, DSC and in vitro digestion techniques. The results indicate that annealing treatment had a significant impact on properties of starches. Annealing treatment reduced the amylose content and increased the damage starch rate of chestnut starches. Starch granules after the annealing treatment exhibited relatively more wrinkles or pores on their surface than native granules. With increasing annealing temperature, the swelling power of chestnut starches revealed a decreasing trend. Meanwhile, the thermal transition temperatures were increased, and the temperature range was decreased, but the enthalpy change was not affected greatly. The in vitro digestibility of chestnut starches was affected significantly by annealing treatment. Annealing treatment caused a decrease in the RDS content and an increase in the SDS content of chestnut starch, respectively.