莲藕淀粉RVA谱特征和淀粉粒形态的研究

 对莲藕根状茎成熟期淀粉特性的研究结果表明: 4个品种表观直链淀粉含量(AAC) 从高到低依次为‘美人红’、‘鄂莲1号’、‘鄂莲4号’和‘武植2号’。根状茎中淀粉粒形态主要有近圆球形和长椭球形两种, 武植2号和鄂莲4号近圆球形淀粉粒明显多于鄂莲1号、美人红。武植2号和鄂莲4号的淀粉糊化特性相似, 其峰值粘度均较高, 冷胶粘度显著低于峰值粘度, 且回复值较小, 消减值为负值; 鄂莲1号和美人红的峰值粘度均较小, 冷胶粘度接近甚至大于峰值粘度, 回复值、消减值均显著大于武植2号和鄂莲4号。AAC与峰值粘度和崩解值呈极显著负相关, r分别为- 0.9748^**和- 0.9793^**, 与回复值、消减值呈极显著正相关, r分别为0.9860^**和0.9804^**, 与冷胶粘度、峰值时间、糊化温度呈显著正相关, r分别为0.9339^*、0.9392^*、0.9130^*。淀粉粒形态结构上的差异可能造成了淀粉糊化特性的差异。

Studies on Starch RVA Profile and Starch Granule Shape in Rhizome of Nelumbo nucifera Gaertn

The research on starch characteristics of matured lotus rhizome indicated that: the sort order of the four lotus varietiesps AAC from the highest to the lowest were: ‘Meirenhong’, ‘Elian 1’, ‘Elian 4’,‘Wuzhi 2’. Pellet and ellipse starch granules were found in lotus rhizome, the number of pellet starch granules in‘Wuzhi 2’and‘Elian 4’was more than in‘Elian 1’and‘Meirenhong’. RVA profile indicated that the starch gelatinization characteristics of‘Wuzhi 2’was similar to‘Elian 4’, their peak viscosity was both high and cool viscositywas below the peak viscosity far away, the consistence was very low and the setback was negative. But in‘Elian 1’and‘Meirenhong’, the peak viscositywas both low and cool viscosity was close to or even higher than peak viscosity, consistence and setback were significantly higher than the other two varieties. AAC in lotus rhizome was negatively correlated with peak viscosity and breakdown, with significant coefficientsof - 0.9748^**and - 0.9793^**, but positively to consistence, setback, cool viscosity, peak time and pasting temperature with significant coefficients of 0.9860^**, 0.9804^**, 0.9339^*, 0.9392^* and 0.9130^*, respectively. The difference of starch granule form and configuration leaded to the difference of the starch gelatinization characteristics.