淀粉表面结合脂对板栗淀粉糊化特性的影响

Effects of Starch-Surface-Lipid on Pasting Property of Starch in Chinese Chestnut (Castanea mollissima)

以中国不同板栗产区16个品种板栗为试材,研究淀粉表面结合脂对板栗淀粉糊化特性影响。结果表明:板栗淀粉RVA糊化黏度在升温过程中逐渐升高并达到峰值,随后黏度降低并在整个温度保持阶段持续降低并降到谷值;在冷却过程中,淀粉糊黏度再次缓慢升高直至整个糊化过程结束。板栗淀粉RVA糊化黏度特征曲线按形状可分为4种类型,脱脂处理虽不改变淀粉糊化黏度特征曲线的形状,但对板栗淀粉RVA糊化黏度特征值产生影响,使峰值黏度、谷值黏度和最终黏度升高,糊化温度降低,峰值时间影响不大,对稀懈值和回冷值有显著影响。当板栗淀粉表面结合脂含量为0.96%～4.50%时,峰值黏度、谷值黏度、最终黏度和稀懈值受到显著影响,从而影响淀粉的糊化特性。

Sixteen Chinese chestnut （Castanea mollissima） varieties collected from different areas of China were used to study the effects of starch-surface-lipid on pasting property of chestnut starch. RVA-pasting viscosity of chestnut starch with de-fatting treatment gradually increased, and reached a peak during the whole warming period at 50 ℃ for 1 min. However, the RVA-pasting viscosity declined to the lowest when starch was warmed at 95 ℃. A following cooling at 12 ℃ brought, the RVA-pasting viscosity to slowly increased again until the whole process ended. Moreover, curves of the RVA-pasting viscosity in chestnut starch, expressed four types in terms of their shapes. The de-fatting treatment did not change shape of curve, but modified the characteristic values of the RVA-pasting viscosity quite largely. The three characteristic values ‘PEAK’, ‘THROUGH’ and ‘FINAL’ increased while the characteristic value ‘PASTING TEMPERATURE’ decreased after the chestnut starch lost its fat. De-fatting of chestnut starch did not affect the ‘PEAK TIME’ of the RVA-pasting viscosity, but interfered the ‘BREAKDOWN’ and ‘SETBACK’ of the RVA-pasting viscosity, depending on chestnut cultivars. When the starch-surface-lipid content was in a range 0.96% to 4.50% the pasting property of chestnut starch was obviously affected regarding to ‘PEAK’, ‘THROUGH’, ‘FINAL’ and ‘BREAKDOWN’ in the characteristic values of the RVA-pasting viscosity.