不同品种稻米淀粉的理化性质与链长分布关系研究

以特糯2072、特优2035、Ⅱ优838和冈优188 4种直链淀粉含量不同的籼稻为材料,采用碱法提取淀粉,通过黏度速测仪(RVA)、激光粒度分析仪及离子交换色谱法研究稻米淀粉的糊化特性、粒径分布与支链淀粉链长组成的相关性。结果表明,4种稻米淀粉颗粒的平均粒径为4.98~5.30μm,与直链淀粉含量呈显著负相关关系(P0.05)。4种稻米淀粉糊化特性差异显著,特优2035具有最高的峰值黏度,而特糯2072的峰值黏度最低。支链淀粉的链长分布影响稻米淀粉的RVA谱特性,成糊温度与DP6-11呈显著负相关关系,与DP12-23呈显著正相关关系(P0.05);崩解值与DP6-11呈极显著正相关关系(P0.01),与DP12-23呈显著负相关关系(P0.05);而消减值与DP≥24呈显著负相关关系(P0.05)。

Relationship between physicochemical properties and branch chain length distributions of different rice starches

Rice starches were separated from four kinds of indica rice,such as Tenuo 2072,Teyou 2035,Ⅱ you 838 and Gangyou 188.The pasting characteristics,particle size distribution,and branch chain length distribution of amylopectin were analyzed by rapid viscosity analyzer,laser particle analyzer,and ion chromatography,respectively.The results show that the average particle size of four rice starches ranged from 4.98 ～ 5.30 μm,which was negatively correlated with the amylose content (P ＜ O.05).The pasting properties showed that Teyou 2035 had the highest peak viscosity,while Tenuo 2072 had the lowest peak viscosity.The chain length distribution of amylopectin had important effects on RVA profiles.The pasting temperature was negatively correlated with DP6-11,but was positively correlated with DP12-23 (P ＜ 0.05).Breakdown viscosity was positively correlated with DP6-11 (P ＜ 0.01),but was negatively correlated with DP12-23 (P ＜ O.05).Moreover,setback viscosity was negatively correlated with DP ≥ 24 (P ＜ 0.05).